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Journal articles on the topic 'Quantum Dot Photocatalysis'

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Author: Grafiati

Published: 6 September 2023

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1

Chu, Kuan-Wu, Sher Lee, Chi-Jung Chang, and Lingyun Liu. "Recent Progress of Carbon Dot Precursors and Photocatalysis Applications." Polymers 11, no. 4 (April 16, 2019): 689. http://dx.doi.org/10.3390/polym11040689.

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Carbon dots (CDs), a class of carbon-based sub-ten-nanometer nanoparticles, have attracted great attention since their discovery fifteen years ago. Because of the outstanding photoluminescence properties, photostability, low toxicity, and low cost, CDs have potential to replace traditional semiconductor quantum dots which have serious drawbacks of toxicity and high cost. This review covers the common top-down and bottom-up methods for the synthesis of CDs, different categories of CD precursors (small molecules, natural polymers, and synthetic polymers), one-pot and multi-step methods to produce CDs/photocatalyst composites, and recent advances of CDs on photocatalysis applications mostly in pollutant degradation and energy areas. A broad range of precursors forming fluorescent CDs are discussed, including small molecule sole or dual precursors, natural polymers such as pure polysaccharides and proteins and crude bio-resources from plants or animals, and various synthetic polymer precursors with positive, negative, neutral and hydrophilic, hydrophobic, or zwitterionic feature. Because of the wide light absorbance, excellent photoluminescence properties and electron transfer ability, CDs have emerged as a new type of photocatalyst. Recent work of CDs as sole photocatalyst or in combination with other materials (e.g., metal, metal sulfide, metal oxide, bismuth-based semiconductor, or other traditional photocatalysts) to form composite catalyst for various photocatalytic applications are reviewed. Possible future directions are proposed at the end of the article on mechanistic studies, production of CDs with better controlled properties, expansion of polymer precursor pool, and systematic studies of CDs for photocatalysis applications.

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2

Chepape, Kgobudi Frans, Thapelo Prince Mofokeng, Pardon Nyamukamba, Kalenga Pierre Mubiayi, and Makwena Justice Moloto. "Enhancing Photocatalytic Degradation of Methyl Blue Using PVP-Capped and Uncapped CdSe Nanoparticles." Journal of Nanotechnology 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/5340784.

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Quantum confinement of semiconductor nanoparticles is a potential feature which can be interesting for photocatalysis, and cadmium selenide is one simple type of quantum dot to use in the following photocatalytic degradation of organic dyes. CdSe nanoparticles capped with polyvinylpyrrolidone (PVP) in various concentration ratios were synthesized by the chemical reduction method and characterized. The transmission electron microscopy (TEM) analysis of the samples showed that 50% PVP-capped CdSe nanoparticles were uniformly distributed in size with an average of 2.7 nm and shape which was spherical-like. The photocatalytic degradation of methyl blue (MB) in water showed efficiencies of 31% and 48% when using uncapped and 50% PVP-capped CdSe nanoparticles as photocatalysts, respectively. The efficiency of PVP-capped CdSe nanoparticles indicated that a complete green process can be utilized for photocatalytic treatment of water and waste water.

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3

Wang, Ruili, Yuequn Shang, Pongsakorn Kanjanaboos, Wenjia Zhou, Zhijun Ning, and Edward H. Sargent. "Colloidal quantum dot ligand engineering for high performance solar cells." Energy & Environmental Science 9, no. 4 (2016): 1130–43. http://dx.doi.org/10.1039/c5ee03887a.

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Colloidal quantum dots (CQDs) are fast-improving materials for next-generation solution-processed optoelectronic devices such as solar cells, photocatalysis, light emitting diodes, and photodetectors.

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4

Kande, Bhupendra, and Prachi Parmar. "Carbon Quantum Dot and Application: A Review." Spectrum of Emerging Sciences 2, no. 1 (April 22, 2022): 11–24. http://dx.doi.org/10.55878/ses2022-2-1-3.

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Non-toxic, fluorescent carbon nanoparticles or carbon quantum dots or carbon dots, a brand new category of carbon material, had high interest due to its optical and fluorescence properties with advantages of eco-friendly, low coast and simple way of synthesis. Their physical – chemical properties also depend to on functionalization and surface passivation. From the discovery of non – toxic caron nano materials, CQDs had numerous applications in different areas like sensing, biological sensing, vivo and vitro imaging, nano drug, drug carrier, drug delivery, energy, food industry, agriculture, photocatalysis and electrocatalysis etc. Here, we described here, the methods of synthesis and functionalization of carbon quantum dots, properties and applications with future prospects.

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5

Qi, Houjuan, Cai Shi, Xiaona Jiang, Min Teng, Zhe Sun, Zhanhua Huang, Duo Pan, Shouxin Liu, and Zhanhu Guo. "Constructing CeO2/nitrogen-doped carbon quantum dot/g-C3N4 heterojunction photocatalysts for highly efficient visible light photocatalysis." Nanoscale 12, no. 37 (2020): 19112–20. http://dx.doi.org/10.1039/d0nr02965c.

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Ternary CeO₂/nitrogen-doped carbon quantum dot (NCQD)/graphitic carbon nitride (g-C₃N₄) heterojunction nanocomposites were prepared and tested for degrading tetracycline (TC) and generating H₂.

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6

Li, Lingwei, Hange Feng, Xiaofan Wei, Kun Jiang, Shaolin Xue, and Paul K. Chu. "Ag as Cocatalyst and Electron-Hole Medium in CeO2 QDs/Ag/Ag2Se Z-scheme Heterojunction Enhanced the Photo-Electrocatalytic Properties of the Photoelectrode." Nanomaterials 10, no. 2 (January 31, 2020): 253. http://dx.doi.org/10.3390/nano10020253.

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A recyclable photoelectrode with high degradation capability for organic pollutants is crucial for environmental protection and, in this work, a novel CeO2 quantum dot (QDs)/Ag2Se Z-scheme photoelectrode boasting increased visible light absorption and fast separation and transfer of photo-induced carriers is prepared and demonstrated. A higher voltage increases the photocurrent and 95.8% of tetracycline (TC) is degraded by 10% CeO2 QDs/Ag2Se in 75 minutes. The degradation rate is superior to that achieved by photocatalysis (92.3% of TC in 90 min) or electrocatalysis (27.7% of TC in 90 min). Oxygen vacancies on the CeO2 QDs advance the separation and transfer of photogenerated carriers at the interfacial region. Free radical capture tests demonstrate that •O2−, •OH, and h+ are the principal active substances and, by also considering the bandgaps of CeO2 QDs and Ag2Se, the photocatalytic mechanism of CeO2 QDs/Ag2Se abides by the Z-scheme rather than the traditional heterojunction scheme. A small amount of metallic Ag formed in the photocatalysis process can form a high-speed charge transfer nano channel, which can greatly inhibit the photogenerated carrier recombination, improve the photocatalytic performance, and help form a steady Z-scheme photocatalysis system. This study would lay a foundation for the design of a Z-scheme solar photocatalytic system.

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7

Liu, Yunxin, Jianxin Shi, Qing Peng, and Yadong Li. "CuO Quantum-Dot-Sensitized Mesoporous ZnO for Visible-Light Photocatalysis." Chemistry - A European Journal 19, no. 13 (February 27, 2013): 4319–26. http://dx.doi.org/10.1002/chem.201203316.

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8

Homer, Micaela Kalmek, Ding-Yuan Kuo, Florence Y. Dou, and Brandi Michelle Cossairt. "(Keynote) Photoinduced Charge Transfer from Quantum Dots Measured By Cyclic Voltammetry." ECS Meeting Abstracts MA2022-02, no. 20 (October 9, 2022): 916. http://dx.doi.org/10.1149/ma2022-0220916mtgabs.

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Measuring and modulating charge transfer processes at quantum dot interfaces are crucial steps in the development of quantum dot photocatalysis. In this work, cyclic voltammetry under illumination is demonstrated to measure the rate of photoinduced charge transfer from CdS quantum dots by directly probing the changing oxidation states of a library of model charge acceptors. The voltammetry data demonstrates the presence of long-lived electron donor states generated by native photodoping of the QDs as well as the relationship between driving force and rate of charge transfer. Changes to the voltammograms under illumination follow mechanistic predictions from classic zone diagrams and electrochemical modeling allows for measurement of the rate of productive electron transfer, giving rate constants (104 M-1s-1) that are distinct from the ps dynamics measured by conventional optical spectroscopy methods and that are more closely connected to the quantum yield of photoinduced chemical transformations.

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9

Li, Boyuan, Zhenhua Cao, Shixuan Wang, Qiang Wei, and Zhurui Shen. "BiVO4 quantum dot-decorated BiPO4 nanorods 0D/1D heterojunction for enhanced visible-light-driven photocatalysis." Dalton Transactions 47, no. 30 (2018): 10288–98. http://dx.doi.org/10.1039/c8dt02402b.

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10

Evangelou, Sofia. "Altering Degenerate Four-Wave Mixing and Third-Harmonic Generation in a Coupled Quantum Dot–Metallic Nanoparticle Structure with the Use of the Purcell Effect." Materials Proceedings 4, no. 1 (November 12, 2020): 39. http://dx.doi.org/10.3390/iocn2020-07875.

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The modification of the optical properties of semiconductor quantum dots near plasmonic nanostructures has attracted significant attention in recent years due to the several potential applications of the coupled nanostructures in optoelectronics, biophotonics and quantum technologies, including sensors, light harvesting, quantum information processing and quantum communication, imaging, photocatalysis, solar cells and others. One of the methods for modifying the nonlinear optical susceptibilities in quantum dots near plasmonic nanostructures uses the change of the spontaneous decay rates of quantum emitters due to the Purcell effect in a tailored nanophotonic environment. In this work, using this idea, we study the modification of the third-order nonlinear optical susceptibilities and specifically the phenomena of degenerate four-wave mixing and third-harmonic generation in a quantum dot that is coupled to a spherical metallic nanoparticle. We find that the strong alteration of the quantum dot’s spontaneous decay rate near the metallic nanoparticle gives strong variation, either enhancement or suppression, of the phenomena of degenerate four-wave mixing and third-harmonic generation for different distances of the quantum dot from the surface of the metallic nanoparticle, depending on the electric dipole direction of the quantum dot. We also show that the degree of enhancement or suppression of the nonlinear optical susceptibilities differs for the studied phenomena and it is stronger for degenerate four-wave mixing than for third-harmonic generation. This work may have important potential applications in the creation of nanoscale photonic devices for various technological applications.

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11

Zhang, Xianfeng, Zongqun Li, Shaowen Xu, and Yaowen Ruan. "Carbon quantum dot-sensitized hollow TiO2 spheres for high-performance visible light photocatalysis." New Journal of Chemistry 45, no. 19 (2021): 8693–700. http://dx.doi.org/10.1039/d1nj00501d.

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TiO₂/CQD composites were synthesized through carbon quantum dots covalently attached to the surface of hollow TiO₂ spheres for visible light photocatalytic degradation of organics.

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12

Zhu, Bolin, Xuefei Li, Yue Wang, Na Liu, Ye Tian, and Jinghai Yang. "Visible-light-driven photocatalytic degradation of RhB by carbon-quantum-dot-modified g-C3N4 on carbon cloth." CrystEngComm 23, no. 27 (2021): 4782–90. http://dx.doi.org/10.1039/d1ce00396h.

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13

Zhao, Chenhui, Ying Liang, Wei Li, Yi Tian, Xin Chen, Dezhong Yin, and Qiuyu Zhang. "BiOBr/BiOCl/carbon quantum dot microspheres with superior visible light-driven photocatalysis." RSC Advances 7, no. 83 (2017): 52614–20. http://dx.doi.org/10.1039/c7ra10344a.

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14

Chi, Le Ha, Pham Duy Long, Hoang Vu Chung, Do Thi Phuong, Do Xuan Mai, Nguyen Thi Tu Oanh, Thach Thi Dao Lien, and Le Van Trung. "Galvanic-Cell-Based Synthesis and Photovoltaic Performance of ZnO-CdS Core-Shell Nanorod Arrays for Quantum Dots Sensitized Solar Cells." Applied Mechanics and Materials 618 (August 2014): 64–68. http://dx.doi.org/10.4028/www.scientific.net/amm.618.64.

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Zinc oxide (ZnO) is recognized as one of the most attractive metal oxides because of its direct wide band gap (3.37 eV) and large exciton binding energy (60 meV), which make it promising for various applications in solar cells, gas sensors, photocatalysis and so on. Here, we report a facile synthesis to grow well-aligned ZnO nanorod arrays on SnO2: F (FTO) glass substrates without the ZnO seed layer using a Galvanic-cell-based method at low temperature (<100°C). CdS quantum dot thin films were then deposited on the nanorod arrays in turn by an effective successive ionic layer adsorption and reaction (SILAR) process to form a ZnO/CdS core-shell structure electrode. Structural, morphological and optical properties of the ZnO/CdS nanorod heterojunctions were investigated. The results indicate that CdS quantum dot thin films were uniformly deposited on the ZnO nanorods and the thickness of the CdS shell can be controlled by varying the number of the adsorption and reaction cycles. The number of quantum dots layers affects on photovoltaic performance of the ZnO/CdS core-shell nanorod arrays has been investigated as photoanodes in quantum dots sensitized solar cells.

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15

Ma, Beibei, Liduo Wang, Haopeng Dong, Rui Gao, Yi Geng, Yifeng Zhu, and Yong Qiu. "Photocatalysis of PbS quantum dots in a quantum dot-sensitized solar cell: photovoltaic performance and characteristics." Phys. Chem. Chem. Phys. 13, no. 7 (2011): 2656–58. http://dx.doi.org/10.1039/c0cp02415e.

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16

Wei, Wei, Yongji Yao, Qi Zhao, Zhilong Xu, Qinfan Wang, Zongtao Zhang, and Yanfeng Gao. "Oxygen defect-induced localized surface plasmon resonance at the WO3−x quantum dot/silver nanowire interface: SERS and photocatalysis." Nanoscale 11, no. 12 (2019): 5535–47. http://dx.doi.org/10.1039/c9nr01059a.

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17

Kassahun, Gashaw Beyene. "High Tunability of Size Dependent Optical Properties of ZnO@M@Au (M = SiO2, In2O3, TiO2) Core/Spacer/Shell Nanostructure." Advanced Nano Research 2, no. 1 (January 12, 2019): 1–13. http://dx.doi.org/10.21467/anr.2.1.1-13.

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This theoretical work presents a comparative study of high tunability size dependent optical properties of quantum dot/wire triple layered core shell nanostructure based on the quasi-static approximation of classical electrodynamics embedded in a fixed dielectrics function of host matrix. In this paper, local field enhancement factor (LFEF), refractive index and optical absorbance of nanocomposite are analyzed by varying core size, thickness of spacer and shell as well as dielectrics function of the spacer for the size of the nanocomposite with the range of 20 nm to 40 nm. For both quantum dot and quantum wire triple layered core shell nanostructure (CSNS), there are two resonances in visible and near/in infrared spectral region with high tunability. When the shell thickness increase and therefore increasing the gold content, the surface plasmon resonance (SPR) at the outer interface shifts to higher energy (blue-shifted) and at the inner interface weak peaks and shifted to lower energy (red-shifted). All of three optical properties, depend on core size, dielectrics and thickess of spacer, thickness of shell, shape of composite and filling factor. For the same thickness of spacer and shell of the two configurations, cylindrical triple layered CSNS less pronounced and shifted to infrared red (IR) spectral region which is recommendable for biological and photocatalysis application.

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18

Bajorowicz, Beata, Marek P. Kobylański, Anna Gołąbiewska, Joanna Nadolna, Adriana Zaleska-Medynska, and Anna Malankowska. "Quantum dot-decorated semiconductor micro- and nanoparticles: A review of their synthesis, characterization and application in photocatalysis." Advances in Colloid and Interface Science 256 (June 2018): 352–72. http://dx.doi.org/10.1016/j.cis.2018.02.003.

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19

Yu, Linhui, Yan Huang, Guangcan Xiao, and Danzhen Li. "Application of long wavelength visible light (λ > 650 nm) in photocatalysis with a p-CuO–n-In2O3 quantum dot heterojunction photocatalyst." Journal of Materials Chemistry A 1, no. 34 (2013): 9637. http://dx.doi.org/10.1039/c3ta12207g.

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20

Hu, Haikun, Zhou Lu, Jiasheng Li, and Zongtao Li. "P‐11.3: Manufacturing Quantum Dot Pixel Array via Self‐Assembling on Hydrophobic‐Hydrophilic Transformation Substrate." SID Symposium Digest of Technical Papers 54, S1 (April 2023): 836–40. http://dx.doi.org/10.1002/sdtp.16428.

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Quantum dots (QDs) have been considered next-generation display fluorescent conversion materials due to their excellent color purity and photoluminescence quantum yield. In order to integrate QD with Micro/Mini-LED and other microdevices efficiently, it is necessary to fabricate micro-scale QD pixel arrays. Photolithography is an effective method for fine pattern processing, but conventional photolithographic procedures need to compound QD with a photosensitive curing matrix, which is not conducive to obtaining high color purity QD pixels. Therefore, a QD self-assembly strategy based on a hydrophobic-hydrophilic transformation substrate is proposed, combining ultraviolet (UV) mask exposure and surface charge modification technology to manufacture a high-purity QD pixel array. In this paper, the hydrophobic-hydrophilic transformation substrate is prepared by polyvinylidene fluoride (PVDF)/TiO2 hybrid fibrous membrane substrate. By changing the thickness of the substrate and analyzing its threshold of the photocatalysis time and pattern accuracy combined with the transmittance after encapsulation, the optimal substrate thickness is about 30 um. On this basis, the surface charge of the fibrous membrane is further modified by poly(diallyldimethylammonium chloride) (PDDA) to enhance the self-assembly performance of the QD in the hydrophilic region. The dimensional accuracy and optical characteristic of the QD pixel array have been studied in detail. The color average degree is 96.4%, the consistency is 94.5%, and the dimensional accuracy error is 5.2%. The spectrum of the QD pixel is almost the same as the QD solution, and the transmittance of the films is up to 88.8% under the visible light wave band, which has excellent optical performance. Therefore, this strategy is beneficial for efficiently manufacturing the high-purity QD pixel array, which has a broad application prospect in the high-resolution display field of Micro/Mini light-emitting diodes (LEDs).

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21

Kang, Chao, Ying Huang, Hui Yang, Xiu Fang Yan, and Zeng Ping Chen. "A Review of Carbon Dots Produced from Biomass Wastes." Nanomaterials 10, no. 11 (November 23, 2020): 2316. http://dx.doi.org/10.3390/nano10112316.

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The fluorescent carbon dot is a novel type of carbon nanomaterial. In comparison with semiconductor quantum dots and fluorescence organic agents, it possesses significant advantages such as excellent photostability and biocompatibility, low cytotoxicity and easy surface functionalization, which endow it a wide application prospect in fields of bioimaging, chemical sensing, environmental monitoring, disease diagnosis and photocatalysis as well. Biomass waste is a good choice for the production of carbon dots owing to its abundance, wide availability, eco-friendly nature and a source of low cost renewable raw materials such as cellulose, hemicellulose, lignin, carbohydrates and proteins, etc. This paper reviews the main sources of biomass waste, the feasibility and superiority of adopting biomass waste as a carbon source for the synthesis of carbon dots, the synthetic approaches of carbon dots from biomass waste and their applications. The advantages and deficiencies of carbon dots from biomass waste and the major influencing factors on their photoluminescence characteristics are summarized and discussed. The challenges and perspectives in the synthesis of carbon dots from biomass wastes are also briefly outlined.

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22

Lan, Shanyou, Ziguo Lin, Da Zhang, Yongyi Zeng, and Xiaolong Liu. "Photocatalysis Enhancement for Programmable Killing of Hepatocellular Carcinoma through Self-Compensation Mechanisms Based on Black Phosphorus Quantum-Dot-Hybridized Nanocatalysts." ACS Applied Materials & Interfaces 11, no. 10 (February 18, 2019): 9804–13. http://dx.doi.org/10.1021/acsami.8b21820.

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23

Rajender, Gone, Jitendra Kumar, and P. K. Giri. "Interfacial charge transfer in oxygen deficient TiO2-graphene quantum dot hybrid and its influence on the enhanced visible light photocatalysis." Applied Catalysis B: Environmental 224 (May 2018): 960–72. http://dx.doi.org/10.1016/j.apcatb.2017.11.042.

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24

Wang, Ruiling, Tian Xie, Zhiyong Sun, Taofei Pu, Weibing Li, and Jin-Ping Ao. "Graphene quantum dot modified g-C3N4 for enhanced photocatalytic oxidation of ammonia performance." RSC Advances 7, no. 81 (2017): 51687–94. http://dx.doi.org/10.1039/c7ra07988e.

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25

Li, Zesheng, Bolin Li, Shaohong Peng, Dehao Li, Siyuan Yang, and Yueping Fang. "Novel visible light-induced g-C3N4 quantum dot/BiPO4 nanocrystal composite photocatalysts for efficient degradation of methyl orange." RSC Adv. 4, no. 66 (2014): 35144–48. http://dx.doi.org/10.1039/c4ra05749j.

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Novel g-C₃N₄ quantum dot/BiPO₄ nanocrystal heterostructured photocatalysts have been synthesized; the photocatalytic activity for degradation of methyl orange as been significantly improved under visible light (λ > 420 nm) irradiation.

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26

Kong, Zhouzhou, Xingzhu Chen, Wee-Jun Ong, Xiujian Zhao, and Neng Li. "Atomic-level insight into the mechanism of 0D/2D black phosphorus quantum dot/graphitic carbon nitride (BPQD/GCN) metal-free heterojunction for photocatalysis." Applied Surface Science 463 (January 2019): 1148–53. http://dx.doi.org/10.1016/j.apsusc.2018.09.026.

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27

Belhacova, Lenka, Hana Bibova, Tereza Marikova, Martin Kuchar, Radek Zouzelka, and Jiri Rathousky. "Removal of Ampicillin by Heterogeneous Photocatalysis: Combined Experimental and DFT Study." Nanomaterials 11, no. 8 (August 3, 2021): 1992. http://dx.doi.org/10.3390/nano11081992.

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A long-term exposition of antibiotics represents a serious problem for the environment, especially for human health. Heterogeneous photocatalysis opens a green way for their removal. Here, we correlated the structural-textural properties of TiO2 photocatalysts with their photocatalytic performance in ampicillin abatement. The tested nanoparticles included anatase and rutile and their defined mixtures. The nominal size range varied from 5 to 800 nm, Aeroxide P25 serving as an industrial benchmark reference. The degradation mechanism of photocatalytic ampicillin abatement was studied by employing both experimental (UPLC/MS/MS, hydroxyl radical scavenger) and theoretical (quantum calculations) approaches. Photocatalytic activity increased with the increasing particle size, generally, anatase being more active than rutile. Interestingly, in the dark, the ampicillin concentration decreased as well, especially in the presence of very small nanoparticles. Even if the photolysis of ampicillin was negligible, a very high degree of mineralization of antibiotic was achieved photocatalytically using the smallest nanoparticles of both allotropes and their mixtures. Furthermore, for anatase samples, the reaction rate constant increases with increasing crystallite size, while the degree of mineralization decreases. Importantly, the suggested degradation pathway mechanism determined by DFT modeling was in very good agreement with experimentally detected reaction products.

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28

Awang, Huzaikha, Tim Peppel, and Jennifer Strunk. "Photocatalytic Degradation of Diclofenac by Nitrogen-Doped Carbon Quantum Dot-Graphitic Carbon Nitride (CNQD)." Catalysts 13, no. 4 (April 13, 2023): 735. http://dx.doi.org/10.3390/catal13040735.

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In this study nitrogen-doped carbon quantum dots/graphitic carbon nitride nanosheet (CNQD) composites with different contents of nitrogen-doped carbon quantum dots (NCQDs; 2, 4, 6, and 8 wt%) were synthesized. The morphological, physicochemical, and photoelectrochemical properties were investigated using complementary methods such as scanning electron microscopy (SEM), powder X-ray diffraction (pXRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectroscopy in diffuse reflectance (DRS), photoluminescence (PL), nitrogen physisorption (BET), photocurrent response, and electrochemical impedance spectroscopy (EIS). The photocatalytic activity of the synthesized materials was assessed during diclofenac (DCF) degradation in an aqueous solution under visible light irradiation. As a result, improved photocatalytic efficiency in DCF degradation was observed for all the CNQD composites compared with bulk graphitic carbon nitride (bCN) and nanosheet g-C3N4 (CNS). The fastest DCF degradation was observed for the 6 wt% NCQD on the surface of CNS (CNQD-6), which removed 62% of DCF in 3 h, with an associated k value of 5.41 × 10−3 min−1. The performance test results confirmed the contribution of NCQDs to enhancing photocatalytic activity, leading to an improvement factor of 1.24 over bCN. The morphology of the CNS and the synergistic interaction between NCQDs and CNS were essential elements for enhancing photocatalytic activity. The photoelectrochemical data and photoluminescence analyses showed the efficient migration of photoexcited electrons from NCQDs to the CNS. The reduced charge recombination rates in CNQD photocatalysts might be due to the synergistic interaction between NCQDs and CNS and the unique up-conversion photoluminescence properties of NCQDs. Further investigations revealed that the photogenerated superoxide radicals (•O2−) predominated in the degradation of DCF, and this photocatalyst had good reusability and toxicity reduction abilities. This work provides insight into the effects of NCQDs on the CNS surface to enhance its potential to remove emerging organic pollutants from water and wastewater.

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Siva Kumar, Nadavala, Mohammad Asif, T. Ranjeth Kumar Reddy, Gnanendra Shanmugam, and Abdelhamid Ajbar. "Silver Quantum Dot Decorated 2D-SnO2 Nanoflakes for Photocatalytic Degradation of the Water Pollutant Rhodamine B." Nanomaterials 9, no. 11 (October 30, 2019): 1536. http://dx.doi.org/10.3390/nano9111536.

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Decoration of 2D semiconductor structures with heterogeneous metal quantum dots has attracted considerable attention due to advanced optical, electrical, and catalytic properties that result from the large surface-to-volume ratio associated with these structures. Herein, we report on silver quantum dot decorated 2D SnO2 nanoflakes for the photocatalytic abatement of water effluents, the synthesis of which was achieved through a straightforward and mild hydrothermal procedure. The photocatalysts were systematically investigated using UV–Vis, XRD, electron microscopy (SEM, HR-TEM), EDX, XPS and FTIR. The photocatalytic activity of the nanostructures was evaluated for the abatement of water pollutant rhodamine B (RhB), under light irradiation. The mild hydrothermal synthesis (100 °C) proved highly efficient for the production of large scale Ag quantum dot (QD)/SnO2 nanoflakes for a novel photocatalytic application. The decoration of SnO2 with Ag QDs significantly enhances the synergetic charge transfer, which diminishes the photo-induced electron-hole reunion. Moreover, the plasmonic effect from Ag QDs and 2D-SnO2 structures acts as an electron tank to collect the photo-induced electrons, generating a Schottky barrier between the SnO2 structures and quantum dots. Overall, this resulted in a facile and efficient degradation of RhB, with a rate double that of pristine SnO2.

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Shao, Xiao, Weiyue Xin, and Xiaohong Yin. "Hydrothermal synthesis of ZnO quantum dot/KNb3O8 nanosheet photocatalysts for reducing carbon dioxide to methanol." Beilstein Journal of Nanotechnology 8 (October 30, 2017): 2264–70. http://dx.doi.org/10.3762/bjnano.8.226.

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ZnO quantum dots and KNb3O8 nanosheets were synthesized by a two-step hydrothermal method for the photocatalytic reduction of CO2 to methanol where isopropanol is simultaneously oxidized to acetone . The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and UV–vis absorption spectroscopy (UV–vis). The photocatalytic activity of the materials was evaluated by formation rate of methanol under UV light irradiation at ambient temperature and pressure. The methanol formation rate of pure KNb3O8 nanosheets was found to be 1257.21 μmol/g/h, and after deposition of 2 wt % ZnO quantum dots on the surface of KNb3O8 nanosheets, the methanol production rate was found to increase to 1539.77 μmol/g/h. Thus, the ZnO quantum dots obviously prompted separation of charge carriers, which was explained by a proposed mechanism for this photocatalytic reaction.

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31

Wei, Maobin, Lili Yang, Yongsheng Yan, and Liang Ni. "Preparation of ZnS quantum dot photocatalyst and study on photocatalytic degradation of antibiotics." Materials Express 9, no. 5 (August 1, 2019): 413–18. http://dx.doi.org/10.1166/mex.2019.1518.

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In this paper, ZnS quantum dot nanomaterials were prepared by means of hydrothermal method and the structure and morphology of the prepared samples were characterized by XRD and transmission electron microscopy (TEM). At the same time, the photocatalytic properties of ZnS quantum dots were studied using antibiotic contaminants ciprofloxacin (CIP) in the environment as the object of degradation. The study showed that the successfully prepared ZnS quantum dot has good photocatalytic property under UV irradiation, it can effectively degrade the antibiotic contaminant ciprofloxacin in the environment, but its catalytic performance under visible light is not high and its degradation efficiency is only 45.75%.

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Tang, Xu, Yang Yu, Changchang Ma, Guosheng Zhou, Xinlin Liu, Minshan Song, Ziyang Lu, and Lei Liu. "The fabrication of a biomass carbon quantum dot-Bi2WO6 hybrid photocatalyst with high performance for antibiotic degradation." New Journal of Chemistry 43, no. 47 (2019): 18860–67. http://dx.doi.org/10.1039/c9nj04764f.

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Chan, Donald K. L., Po Ling Cheung, and Jimmy C. Yu. "A visible-light-driven composite photocatalyst of TiO2 nanotube arrays and graphene quantum dots." Beilstein Journal of Nanotechnology 5 (May 22, 2014): 689–95. http://dx.doi.org/10.3762/bjnano.5.81.

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TiO2 nanotube arrays are well-known efficient UV-driven photocatalysts. The incorporation of graphene quantum dots could extend the photo-response of the nanotubes to the visible-light range. Graphene quantum dot-sensitized TiO2 nanotube arrays were synthesized by covalently coupling these two materials. The product was characterized by Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and UV–vis absorption spectroscopy. The product exhibited high photocatalytic performance in the photodegradation of methylene blue and enhanced photocurrent under visible light irradiation.

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Jia, Dongmei, Xiaoyu Li, Qianqian Chi, Jingxiang Low, Ping Deng, Wenbo Wu, Yikang Wang, et al. "Direct Electron Transfer from Upconversion Graphene Quantum Dots to TiO₂ Enabling Infrared Light-Driven Overall Water Splitting." Research 2022 (April 13, 2022): 1–9. http://dx.doi.org/10.34133/2022/9781453.

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Utilization of infrared light in photocatalytic water splitting is highly important yet challenging given its large proportion in sunlight. Although upconversion material may photogenerate electrons with sufficient energy, the electron transfer between upconversion material and semiconductor is inefficient limiting overall photocatalytic performance. In this work, a TiO2/graphene quantum dot (GQD) hybrid system has been designed with intimate interface, which enables highly efficient transfer of photogenerated electrons from GQDs to TiO2. The designed hybrid material with high photogenerated electron density displays photocatalytic activity under infrared light (20 mW cm-2) for overall water splitting (H2: 60.4 μmol gcat.-1 h-1 and O2: 30.0 μmol gcat.-1 h-1). With infrared light well harnessed, the system offers a solar-to-hydrogen (STH) efficiency of 0.80% in full solar spectrum. This work provides new insight into harnessing charge transfer between upconversion materials and semiconductor photocatalysts and opens a new avenue for designing photocatalysts toward working under infrared light.

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Apostolaki, Maria-Athina, Alexia Toumazatou, Maria Antoniadou, Elias Sakellis, Evangelia Xenogiannopoulou, Spiros Gardelis, Nikos Boukos, Polycarpos Falaras, Athanasios Dimoulas, and Vlassis Likodimos. "Graphene Quantum Dot-TiO2 Photonic Crystal Films for Photocatalytic Applications." Nanomaterials 10, no. 12 (December 21, 2020): 2566. http://dx.doi.org/10.3390/nano10122566.

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Photonic crystal structuring has emerged as an advanced method to enhance solar light harvesting by metal oxide photocatalysts along with rational compositional modifications of the materials’ properties. In this work, surface functionalization of TiO2 photonic crystals by blue luminescent graphene quantum dots (GQDs), n–π* band at ca. 350 nm, is demonstrated as a facile, environmental benign method to promote photocatalytic activity by the combination of slow photon-assisted light trapping with GQD-TiO2 interfacial electron transfer. TiO2 inverse opal films fabricated by the co-assembly of polymer colloidal spheres with a hydrolyzed titania precursor were post-modified by impregnation in aqueous GQDs suspension without any structural distortion. Photonic band gap engineering by varying the inverse opal macropore size resulted in selective performance enhancement for both salicylic acid photocatalytic degradation and photocurrent generation under UV–VIS and visible light, when red-edge slow photons overlapped with the composite’s absorption edge, whereas stop band reflection was attenuated by the strong UVA absorbance of the GQD-TiO2 photonic films. Photoelectrochemical and photoluminescence measurements indicated that the observed improvement, which surpassed similarly modified benchmark mesoporous P25 TiO2 films, was further assisted by GQDs electron acceptor action and visible light activation to a lesser extent, leading to highly efficient photocatalytic films.

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Gao, Huajing, Chengxiang Zheng, Hua Yang, Xiaowei Niu, and Shifa Wang. "Construction of a CQDs/Ag3PO4/BiPO4 Heterostructure Photocatalyst with Enhanced Photocatalytic Degradation of Rhodamine B under Simulated Solar Irradiation." Micromachines 10, no. 9 (August 23, 2019): 557. http://dx.doi.org/10.3390/mi10090557.

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A carbon quantum dot (CQDs)/Ag3PO4/BiPO4 heterostructure photocatalyst was constructed by a simple hydrothermal synthesis method. The as-prepared CQDs/Ag3PO4/BiPO4 photocatalyst has been characterized in detail by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectroscopy, and photoelectrochemical measurements. It is demonstrated that the CQDs/Ag3PO4/BiPO4 composite is constructed by assembling Ag3PO4 fine particles and CQDs on the surface of rice-like BiPO4 granules. The CQDs/Ag3PO4/BiPO4 heterostructure photocatalyst exhibits a higher photocatalytic activity for the degradation of the rhodamine B dye than that of Ag3PO4, BiPO4, and Ag3PO4/BiPO4. The synergistic effects of light absorption capacity, band edge position, separation, and utilization efficiency of photogenerated carriers play the key role for the enhanced photodegradation of the rhodamine B dye.

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Iqbal, Anwar, Fatimah Bukola Shittu, Mohamad Nasir Mohamad Ibrahim, N. H. H. Abu Bakar, Noorfatimah Yahaya, Kalaivizhi Rajappan, M. Hazwan Hussin, Wan Hazman Danial, and Lee D. Wilson. "Photoreactive Carbon Dots Modified g-C3N4 for Effective Photooxidation of Bisphenol-A under Visible Light Irradiation." Catalysts 12, no. 11 (October 25, 2022): 1311. http://dx.doi.org/10.3390/catal12111311.

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A series of carbon dots (CDs) modified g‑C3N4 (xCDs/g-C3N4; x = 0.5, 1.0, and 1.5 mL CDs solution) was synthesized via the microwave-assisted hydrothermal synthesis method for the photooxidation of bisphenol-A (BPA) under visible light irradiation. The X-ray diffraction (XRD) analysis indicates that the CDs may have a turbostratic structure and the resulting photocatalysts have distorted crystal structure, as compared with pure g-C3N4. The high-resolution transmission electron microscope (HR-TEM) analysis revealed amorphous, mono-disperse, spherical CDs with an average particle size of 3.75 nm. The distribution of CDs within the matrix of g‑C3N4 appear as small dark dot-like domains. The N2 adsorption-desorption analysis indicates that the nanocomposites are mesoporous with a density functional theory (DFT) estimate of the pore size distribution between 2–13 nm. The CDs quantum yield (QY) was determined to be 12% using the UV-vis spectral analysis, where the CDs/g‑C3N4 has improved absorption in the visible region than g-C3N4. The higher BET surface area of CDs/g‑C3N4 provided more adsorption sites and the ability to yield photogenerated e−/h+ pairs, which caused the 1.5 CDs/g‑C3N4 to have better photocatalytic efficiency compared to the rest of the systems. The highest removal, 90%, was achieved at the following optimum conditions: BPA initial concentration = 20 mg L−1, catalyst dosage = 30 mg L−1, and pH = 10. The photooxidation process is mainly driven by photogenerated holes (h+) followed by •OH and O2•−. The synthesis of the 1.5 CDs/g‑C3N4 system is simple and cost-effective, where this photocatalyst is highly stable and reusable versus other systems reported in the literature.

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Chen, Liang-Che, Yuan-Kai Xiao, Nei-Jin Ke, Chun-Yan Shih, Te-Fu Yeh, Yuh-Lang Lee, and Hsisheng Teng. "Synergy between quantum confinement and chemical functionality of graphene dots promotes photocatalytic H2 evolution." Journal of Materials Chemistry A 6, no. 37 (2018): 18216–24. http://dx.doi.org/10.1039/c8ta05288c.

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Song, Taeyoung, Jun Young Cheong, Ji Yong Choi, Cheolmin Park, Chulhee Lee, Changsoo Lee, Hyuck Mo Lee, et al. "A feasible strategy to prepare quantum dot-incorporated carbon nanofibers as free-standing platforms." Nanoscale Advances 1, no. 10 (2019): 3948–56. http://dx.doi.org/10.1039/c9na00423h.

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Pashazadeh, Sara, Biuck Habibi, Ali Pashazadeh, Ali Fatemi, and Milad Rasouli. "(Digital Presentation) Facile Fabrication of Graphene Quantum Dot- Doped Polyaniline Embedded Cu Metal-Organic Frameworks Composite Electrode As Improved Anode Electrocatalyst for Methanol Oxidation." ECS Meeting Abstracts MA2022-01, no. 41 (July 7, 2022): 2491. http://dx.doi.org/10.1149/ma2022-01412491mtgabs.

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Nonrenewable energy sources accounted for roughly 80% of total energy consumption [1]. Solar energy, wind energy, geothermal energy, hydropower, and fuel cells (FCs) have all recently been described as renewable energy sources. In commercial uses, renewable energy has experienced meteorological and logistical obstacles. Because of advantages such as simple fabrication/operation conditions, eco-friendly, high energy conversion efficiency, and long-term durability, FCs technologies are considered one of the most important renewable energy sources for many applications such as portable devices, cars, and electricity plants [2–5]. Methanol can be utilized in direct methanol fuel cells (DMFC) to produce clean energy that can be used in smart electronic gadgets or small automobiles in this regard [6]. However, before DMFC can be used commercially, the slow oxidation kinetics and catalyst toxicity [7] must be resolved. Therefore, the development of direct methanol fuel cells (DMFCs) is one of the most promising technologies for the applications of these devices in stationary power supplies and electric vehicles [8]. Apart from the future of mobile devices such as mobile chargers, phones, computers, and many other applications, this energy is environmentally benign because no gases are emitted and the waste is simply clean water. The biggest issue that this technique may encounter is its high cost due to the usage of noble metal catalysts (platinum (Pt) and ruthenium (Ru)) [9]. Methanol is oxidized via a multi-electron process and several products and/or intermediates can be formed, depending on the electrolyte and the nature of the electrode. Electrode materials are important parameters in the electrochemical oxidation of methanol, where high efficient electrocatalysts are needed. Several metal oxides such as Fe2O3, CeO2, MoOx, Co3O4, NiO, and CuO has been used in various applications, such as catalysis, water splitting photocatalysis, solar cells and gas sensing, besides their uses to enhance the electrocatalytic activity for methanol oxidation [10-11]. This paper describes the preparation of graphene quantum dot-doped polyaniline embedded copper metal-organic frameworks composite catalysts for investigating methanol oxidation in alkaline solutions. The electrode surface was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and electrochemical impedance spectroscopy (EIS). After physicochemical characterizations of graphene quantum dot-doped polyaniline embedded copper metal-organic frameworks composite modified carbon ceramic electrode (Cu- MOF/GQDs-PAN/CCE), its electrocatalytic and stability characterizations toward methanol oxidation in alkaline media were investigated in detail by cyclic voltammetry and chronoamperometry. Results showed that, the electrocatalytic activity of the Cu- MOF/GQDs-PAN/CCE electrode is much higher than those of unmodified electrode under similar experimental conditions, showing the possibility of attaining good electrocatalytic anodes for fuel cells. Kinetic parameters such as the electron transfer coefficient (α) and the number of electrons involved in the rate determining step (nα) for the oxidation of methanol were determined utilizing cyclic voltammetry (CV). Keywords: Graphene quantum dot, Polyaniline, Metal-organic frameworks, electrocatalyst, Methanol References [1] S.K. Kamarudin, F. Ahmad, W.R.W. Daud, Overview on application of direct methanol fuel cell (DMFC) for portable electronic devices, Int. J. Hydrog. Energy 34 (2009) 6902–6916. [2] L. Carrette, K.A. Friedrich, U. Stimming, Fuel cells: principles, types, fuels and applications, ChemPhysChem 1 (2000) 162–193. [3] A.B. Stambouli, Fuel cells: The expectations for an environmental-friendly and sustainable source of energy, Renew. Sustain. Energy Rev. 15 (9) (2011) 4507– 4520. [4] P. Joghee, J.N. Malik, S. Pylypenko, R. O’Hayre, A review on direct methanol fuel cells – In the perspective of energy and sustainability, MRS Energy Sustain. 2 (2015), https://doi.org/10.1557/mre.2015.4. [5] D. Hassen, M.A. Shenashen, S.A. El-Safty, M.M. Selim, H. Isago, A. Elmarakbi, H. Yamaguchi, Nitrogen-doped carbon-embedded TiO2 nanofibers as promising oxygen reduction reaction electrocatalysts, J. Power Sources 330 (2016) 292– 303. [6] M. Mansor, S.N. Timmiati, K.L. Lim, W.Y. Wong, S.K. Kamarudin, N.H. Nazirah Kamarudin, Recent progress of anode catalysts and their support materials for methanol electrooxidation reaction, Int. J. Hydrogen Energy 44 (29) (2019) 14744–14769, https://doi.org/10.1016/j.ijhydene.2019.04.100. [7] Z. Mousavi, A. Benvidi, S. Jahanbani, M. Mazloum-Ardakani, R. Vafazadeh, H. R. Zare, Investigation of electrochemical oxidation of methanol at a carbon paste electrode modified with Ni(II)-BS complex and reduced graphene oxide nano sheets, Electroanalysis 28 (12) (2016) 2985–2992, https://doi.org/10.1002/ elan.201501183. [8] S. Wasmus, A. Küver, Methanol oxidation and direct methanol fuel cells: a selective review, J. Electroanal. Chem. 461 (1-2) (1999) 14–31. [9] M. Liu, R. Zhang, W. Chen, Graphene-Supported Nanoelectrocatalysts for Fuel Cells: Synthesis, Properties, and Applications, Chem. Rev. 114 (2014) 5117– 5160. [10] N. Spinner, W.E. Mustain, Electrochim. Acta 56 (2011) 5656. [11] M.S. Risbud, S. Baxter, M. Skyllas-Kazacos, Open Fuels Energy Sci. J. 5 (2012) 9.

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Wang, Ke, Zipeng Xing, Meng Du, Shiyu Zhang, Zhenzi Li, Kai Pan, and Wei Zhou. "Plasmon Ag and CdS quantum dot co-decorated 3D hierarchical ball-flower-like Bi5O7I nanosheets as tandem heterojunctions for enhanced photothermal–photocatalytic performance." Catalysis Science & Technology 9, no. 23 (2019): 6714–22. http://dx.doi.org/10.1039/c9cy01945f.

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Bi₅O₇I/Ag/CdS tandem heterojunction photocatalysts show excellent photothermal and photocatalytic performance, which is attributed to the formation of tandem heterojunctions, surface plasmon resonance, and 3D hierarchical structure.

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Sun, Qianqian, Zebin Yu, Ronghua Jiang, Yanping Hou, Lei Sun, Lun Qian, Fengyuan Li, Mingjie Li, Qi Ran, and Heqing Zhang. "CoP QD anchored carbon skeleton modified CdS nanorods as a co-catalyst for photocatalytic hydrogen production." Nanoscale 12, no. 37 (2020): 19203–12. http://dx.doi.org/10.1039/d0nr05268j.

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Chandrashekar, Hediyala B., Arun Maji, Ganga Halder, Sucheta Banerjee, Sayan Bhattacharyya, and Debabrata Maiti. "Photocatalyzed borylation using water-soluble quantum dots." Chemical Communications 55, no. 44 (2019): 6201–4. http://dx.doi.org/10.1039/c9cc01737b.

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Grewal, Jaspreet Kaur, Manpreet Kaur, Kousik Mandal, and Virender K. Sharma. "Carbon Quantum Dot-Titanium Doped Strontium Ferrite Nanocomposite: Visible Light Active Photocatalyst to Degrade Nitroaromatics." Catalysts 12, no. 10 (September 27, 2022): 1126. http://dx.doi.org/10.3390/catal12101126.

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The synthesis of carbon quantum dots (CQDs) from agricultural waste is a promising approach for waste valorization. In the present work, CQDs were synthesized using sugarcane bagasse as a carbon precursor. The nanocomposite of CQDs with trimetallic strontium–titanium ferrite was synthesized with an ultrasonication approach. The structural, magnetic and optical features of the synthesized nanocomposite and pristine NPs were studied using different analytical techniques. The TEM micrograph of the nanocomposite reveals the distribution of CQDs (8–10 nm) along with the agglomerated ferrite NPs. To validate the results, the photocatalytic efficiency of the nanocomposite, NPs and CQDs was comparatively studied for the photodegradation of nitroaromatic pollutants viz. p-nitrophenol, martius yellow and pendimethalin under visible-light irradiation. A nanocomposite having a 2:1 w:w ratio of CQDs and Sr0.4Ti0.6Fe2O4.6 displays an excellent photocatalytic performance, with the degradation efficiency ranging from 91.2 to 97.4%, as compared with 65.0–88.3% for pristine NPs and CQDs. These results were supported by band gap and photoluminescence analyses. The promising photocatalytic potential of the nanocomposite over the pristine CQDs and ferrite NPs could be ascribed to the increased specific-surface area (101.3 m2/g), lowering in band gap coupled with fluorescence-quenching which facilitated the transfer of photoinduced charge carriers. The impact of parameters affecting the photocatalytic process viz. pH, catalyst dose and contact time was also investigated. On the basis of quenching and gas chromatography-mass spectrometry (GC-MS) studies, plausible degradation pathways were proposed. The results highlight the broad potential of designing substituted ferrite-CQDs-based nanocomposites as reusable and visible-light-driven photocatalysts.

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Yuan, Yucheng, Na Jin, Peter Saghy, Lacie Dube, Hua Zhu, and Ou Chen. "Quantum Dot Photocatalysts for Organic Transformations." Journal of Physical Chemistry Letters 12, no. 30 (July 26, 2021): 7180–93. http://dx.doi.org/10.1021/acs.jpclett.1c01717.

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Ren, Zhixin, Huachao Ma, Jianxin Geng, Cuijuan Liu, Chaoyu Song, and Yuguang Lv. "ZnO QDs/GO/g-C3N4 Preparation and Photocatalytic Properties of Composites." Micromachines 14, no. 8 (July 26, 2023): 1501. http://dx.doi.org/10.3390/mi14081501.

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Using an ultrasound-assisted chemical technique, ZnO quantum dot and ZnO composites were created. The optical characteristics and structural details of these composites were examined using TEM, XRD, XPS, FT-IR, UV-vis, and BET. The results revealed that both the ZnO quantum dot composite and ZnO composite exhibited outstanding optical properties, making them suitable for photocatalytic reactions. In order to analyze the photocatalytic performance, a degradation experiment was conducted using Rhodamine B solution as the simulation dye wastewater. The experiment demonstrated that the degradation of Rhodamine B followed the first-order reaction kinetics equation when combined with the photocatalytic reaction kinetics. Moreover, through cyclic stability testing, it was determined that the ZnO QDs-GO-g-C3N4 composite sample showed good stability and could be reused. The degradation rates of Rhodamine B solution using ZnO-GO-g-C3N4 and ZnO QDs-GO-g-C3N4 reached 95.25% and 97.16%, respectively. Furthermore, free-radical-trapping experiments confirmed that ·O2− was the main active species in the catalytic system and its photocatalytic mechanism was elucidated. The photocatalytic oxidation of ZnO quantum dots in this study has important reference value and provides a new idea for the subsequent research.

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Aydogdu, Seyda, Arzu Hatipoglu, Bahar Eren, and Yelda Gurkan. "Photodegradation kinetics of organophosphorous with hydroxyl radicals: Experimental and theoretical study." Journal of the Serbian Chemical Society, no. 00 (2021): 56. http://dx.doi.org/10.2298/jsc210409056a.

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The presence of organophosphorus compounds (OPs) in the environmental counterparts has become an important problem because of their toxicity. In this study, the photocatalytic degradation reactions of the three OPs with hydroxyl radical were investigated by both experimental and quantum chemical methods. Photocatalytic degradation kinetics of the examined organophosphorus compounds were investigated under UV-A irradiation using TiO2 as the photocatalyst. The effects of the initial concentrations on the degradation rate have been examined. There was an observable loss of OPs in the presence of TiO2 photocatalyst under UV-A at 0.2 g TiO2 per 100 mL. The quantum chemical calculations have been carried out by the density functional theory (DFT) at B3LYP/6-31g(d) level. The reaction pathways were modelled to find the most probable mechanism for OPs with the OH radical and to determine the primary intermediates. The rate constants of the eight reaction paths were calculated by the transition state theory. Conductor-like polarizable continuum model (CPCM) was used as the solvation model with the intention of understanding the water effect. The theoretical results were in agreement with experimental ones.

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Ji, Yi, Quan Zuo, Chuanshuang Chen, Yannan Liu, Yiyong Mai, and Yongfeng Zhou. "A supramolecular single-site photocatalyst based on multi-to-one Förster resonance energy transfer." Chemical Communications 57, no. 34 (2021): 4174–77. http://dx.doi.org/10.1039/d1cc01339d.

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Budimir, Milica, Zoran Marković, Dragana Jovanović, Miloš Vujisić, Matej Mičušík, Martin Danko, Angela Kleinová, Helena Švajdlenková, Zdeno Špitalský, and Biljana Todorović Marković. "Correction: Gamma ray assisted modification of carbon quantum dot/polyurethane nanocomposites: structural, mechanical and photocatalytic study." RSC Advances 10, no. 12 (2020): 7125. http://dx.doi.org/10.1039/d0ra90015j.

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Correction for ‘Gamma ray assisted modification of carbon quantum dot/polyurethane nanocomposites: structural, mechanical and photocatalytic study’ by Milica Budimir et al., RSC Adv., 2019, 9, 6278–6286.

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Huang, Jinzhao, Song Liu, Lei Kuang, Yongdan Zhao, Tao Jiang, Shiyou Liu, and Xijin Xu. "Enhanced photocatalytic activity of quantum-dot-sensitized one-dimensionally-ordered ZnO nanorod photocatalyst." Journal of Environmental Sciences 25, no. 12 (December 2013): 2487–91. http://dx.doi.org/10.1016/s1001-0742(12)60330-1.

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