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Journal articles on the topic 'Photovoltaic Devices - Semiconductor Nanocrystals'

Author: Grafiati

Published: 7 September 2023

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1

Qiao, Fen. "Semiconductor Nanocrystals for Photovoltaic Devices." Materials Science Forum 852 (April 2016): 935–38. http://dx.doi.org/10.4028/www.scientific.net/msf.852.935.

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Recently, photovoltaic devices based on colloidal semiconductor nanocrystals (NCs) have attracted a great interest due to their flexible synthesis with tunable band gaps and shape-dependent optical and electronic properties. However, the surface of NCs typically presents long chain with electrically insulating organic ligands, which hinder the device applications for NCs. So the major challenge of NCs for photovoltaic devices application is to decrease the inter NC space and the height of the tunnel barriers among NCs, therefore increase the transport properties of NCs. In this article, recent development of colloidal semiconductor NCs and possible routes for improving transport properties of colloidal NCs were reviewed. Among those methods, the thermal annealing approach provides a simple and cost-effective way to fabricate superlattice and to decrease the inter-space among NCs, which may be used for the preparation of other nanocrystalline superstructure and functional devices.

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Lin, Weyde M. M., Maksym Yarema, Mengxia Liu, Edward Sargent, and Vanessa Wood. "Nanocrystal Quantum Dot Devices: How the Lead Sulfide (PbS) System Teaches Us the Importance of Surfaces." CHIMIA International Journal for Chemistry 75, no. 5 (May 28, 2021): 398–413. http://dx.doi.org/10.2533/chimia.2021.398.

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Semiconducting thin films made from nanocrystals hold potential as composite hybrid materials with new functionalities. With nanocrystal syntheses, composition can be controlled at the sub-nanometer level, and, by tuning size, shape, and surface termination of the nanocrystals as well as their packing, it is possible to select the electronic, phononic, and photonic properties of the resulting thin films. While the ability to tune the properties of a semiconductor from the atomistic- to macro-scale using solution-based techniques presents unique opportunities, it also introduces challenges for process control and reproducibility. In this review, we use the example of well-studied lead sulfide (PbS) nanocrystals and describe the key advances in nanocrystal synthesis and thin-film fabrication that have enabled improvement in performance of photovoltaic devices. While research moves forward with novel nanocrystal materials, it is important to consider what decades of work on PbS nanocrystals has taught us and how we can apply these learnings to realize the full potential of nanocrystal solids as highly flexible materials systems for functional semiconductor thin-film devices. One key lesson is the importance of controlling and manipulating surfaces.

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Dalui, Amit, Ali Hossain Khan, Bapi Pradhan, Jayita Pradhan, Biswarup Satpati, and Somobrata Acharya. "Facile synthesis of composition and morphology modulated quaternary CuZnFeS colloidal nanocrystals for photovoltaic application." RSC Advances 5, no. 118 (2015): 97485–94. http://dx.doi.org/10.1039/c5ra18157g.

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Abulikemu, Mutalifu, Silvano Del Gobbo, Dalaver H. Anjum, Mohammad Azad Malik, and Osman M. Bakr. "Colloidal Sb2S3nanocrystals: synthesis, characterization and fabrication of solid-state semiconductor sensitized solar cells." Journal of Materials Chemistry A 4, no. 18 (2016): 6809–14. http://dx.doi.org/10.1039/c5ta09546h.

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Antimony sulfide nanocrystals of various shapes and different phases are synthesized using a colloidal hot-injection method, and the as-prepared nanocrystals are used as a light harvesting material in photovoltaic devices.

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Hou, Mingyue, Zhaohua Zhou, Ao Xu, Kening Xiao, Jiakun Li, Donghuan Qin, Wei Xu, and Lintao Hou. "Synthesis of Group II-VI Semiconductor Nanocrystals via Phosphine Free Method and Their Application in Solution Processed Photovoltaic Devices." Nanomaterials 11, no. 8 (August 15, 2021): 2071. http://dx.doi.org/10.3390/nano11082071.

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Solution-processed CdTe semiconductor nanocrystals (NCs) have exhibited astonishing potential in fabricating low-cost, low materials consumption and highly efficient photovoltaic devices. However, most of the conventional CdTe NCs reported are synthesized through high temperature microemulsion method with high toxic trioctylphosphine tellurite (TOP-Te) or tributylphosphine tellurite (TBP-Te) as tellurium precursor. These hazardous substances used in the fabrication process of CdTe NCs are drawing them back from further application. Herein, we report a phosphine-free method for synthesizing group II-VI semiconductor NCs with alkyl amine and alkyl acid as ligands. Based on various characterizations like UV-vis absorption (UV), transmission electron microscope (TEM), and X-ray diffraction (XRD), among others, the properties of the as-synthesized CdS, CdSe, and CdTe NCs are determined. High-quality semiconductor NCs with easily controlled size and morphology could be fabricated through this phosphine-free method. To further investigate its potential to industrial application, NCs solar cells with device configuration of ITO/ZnO/CdSe/CdTe/Au and ITO/ZnO/CdS/CdTe/Au are fabricated based on NCs synthesized by this method. By optimizing the device fabrication conditions, the champion device exhibited power conversion efficiency (PCE) of 2.28%. This research paves the way for industrial production of low-cost and environmentally friendly NCs photovoltaic devices.

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Prezioso, S., S. M. Hossain, A. Anopchenko, L. Pavesi, M. Wang, G. Pucker, and P. Bellutti. "Superlinear photovoltaic effect in Si nanocrystals based metal-insulator-semiconductor devices." Applied Physics Letters 94, no. 6 (February 9, 2009): 062108. http://dx.doi.org/10.1063/1.3081410.

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Meng, Lingju, and Xihua Wang. "Doping Colloidal Quantum Dot Materials and Devices for Photovoltaics." Energies 15, no. 7 (March 27, 2022): 2458. http://dx.doi.org/10.3390/en15072458.

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Colloidal semiconductor nanocrystals have generated tremendous interest because of their solution processability and robust tunability. Among such nanocrystals, the colloidal quantum dot (CQD) draws the most attention for its well-known quantum size effects. In the last decade, applications of CQDs have been booming in electronics and optoelectronics, especially in photovoltaics. Electronically doped semiconductors are critical in the fabrication of solar cells, because carefully designed band structures are able to promote efficient charge extraction. Unlike conventional semiconductors, diffusion and ion implantation technologies are not suitable for doping CQDs. Therefore, researchers have creatively developed alternative doping methods for CQD materials and devices. In order to provide a state-of-the-art summary and comprehensive understanding to this research community, we focused on various doping techniques and their applications for photovoltaics and demystify them from different perspectives. By analyzing two classes of CQDs, lead chalcogenide CQDs and perovskite CQDs, we compared different working scenarios of each technique, summarized the development in this field, and raised our own future perspectives.

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Satta, Jessica, Andrea Pinna, Giorgio Pia, Luca Pilia, Carlo Maria Carbonaro, Daniele Chiriu, Luigi Stagi, Qader Abdulqader Abdullah, and Pier Carlo Ricci. "Stable CsPbBr3 Nanocrystals—Decorated Nanoporous Gold for Optoelectronic Applications." Crystals 12, no. 6 (June 18, 2022): 863. http://dx.doi.org/10.3390/cryst12060863.

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Halide perovskite colloidal nanocrystals have recently gained much attention thanks to their superior stability compared with their bulk counterpart and to their unique optical properties. In this paper, two systems combining nanocrystals and nanoporous gold are studied to create an optimal metal semiconductor heterojunction that can be used in photocatalysis and photovoltaic devices. The perovskite degradation phenomenon is observed when the nanoporous gold powder is mixed into the hexane suspension of nanocrystals, while the charge separation efficiency is increased by synthesizing the nanocrystals directly onto the gold porous structure. The analysis of the structural and optical properties evidences an energy transfer efficiency of 47%, along with the high structural stability of the hybrid system.

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9

Nozaki, Tomohiro, Yi Ding, and Ryan Gresback. "Plasma Synthesis of Silicon Nanocrystals: Application to Organic/Inorganic Photovoltaics through Solution Processing." Materials Science Forum 783-786 (May 2014): 2002–4. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.2002.

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Silicon nanocrystals (SiNCs) have unique optical and electronic properties that are advantageous for semiconductor device applications and here their application to solar cell is presented. Free-standing, narrow size distribution SiNCs were synthesized by non-thermal plasma using silicon tetrachloride (SiCl4) successfully. Blended solution of as-produced SiNCs and P3HT, or Poly(3-hexylthiophene-2,5-diyl), was spin-casted to form bulk heterojunction solar cell devices. As the weight fraction of SiNCs increased up to 50 wt%, the short circuit current and the power conversion efficiency dramatically increased, while the open circuit voltage and the fill factor do not change significantly. The improved performance is attributable to increased probability of exciton dissociation at acceptor SiNCs and donor P3HT interface.

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Kovalenko, Maksym V., Loredana Protesescu, and Maryna I. Bodnarchuk. "Properties and potential optoelectronic applications of lead halide perovskite nanocrystals." Science 358, no. 6364 (November 9, 2017): 745–50. http://dx.doi.org/10.1126/science.aam7093.

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Semiconducting lead halide perovskites (LHPs) have not only become prominent thin-film absorber materials in photovoltaics but have also proven to be disruptive in the field of colloidal semiconductor nanocrystals (NCs). The most important feature of LHP NCs is their so-called defect-tolerance—the apparently benign nature of structural defects, highly abundant in these compounds, with respect to optical and electronic properties. Here, we review the important differences that exist in the chemistry and physics of LHP NCs as compared with more conventional, tetrahedrally bonded, elemental, and binary semiconductor NCs (such as silicon, germanium, cadmium selenide, gallium arsenide, and indium phosphide). We survey the prospects of LHP NCs for optoelectronic applications such as in television displays, light-emitting devices, and solar cells, emphasizing the practical hurdles that remain to be overcome.

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Kortshagen, Uwe, Rebeccah Anthony, Ryan Gresback, Zachary Holman, Rebekah Ligman, Chin-Yi Liu, Lorenzo Mangolini, and Stephen A. Campbell. "Plasma synthesis of group IV quantum dots for luminescence and photovoltaic applications." Pure and Applied Chemistry 80, no. 9 (January 1, 2008): 1901–8. http://dx.doi.org/10.1351/pac200880091901.

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The unique ability of nonthermal plasmas to form high-quality nanocrystals (NCs) of covalently bonded semiconductors, including the group IV elements silicon (Si) and germanium (Ge), has been extensively demonstrated over the past few years. Recently, plasma processing was also extended to the surface functionalization of NCs, imparting further functionalities to plasma-produced NCs such as solution-processability or the passivation of electronic surface states. This paper focuses on the synthesis and surface functionalization of Si- and Ge-NCs, and on their application in luminescent and photovoltaic devices.

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Song, Jing, Xiaoxia Xu, Jihuai Wu, and Zhang Lan. "Low-temperature solution-processing high quality Nb-doped SnO2 nanocrystals-based electron transport layers for efficient planar perovskite solar cells." Functional Materials Letters 12, no. 01 (January 21, 2019): 1850091. http://dx.doi.org/10.1142/s1793604718500911.

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Low-temperature solution-processing method is a kind of low-energy-consuming and simple methodology for preparing cost-effective planar perovskite solar cells (PSCs). To achieve high-effciency planar PSCs, the quality of electron-transporting layers (ETLs) play a key role. The solvothermal-synthesized organic ligands capped semiconductor nanocrystals (NCs) not only have high crystallinity but also show excellent film-formation. Nevertheless, the biggest problem is that these organic ligands will form insulating barriers around the NCs, which will seriously hinder electronic coupling and limit performance of the corresponding devices. Therefore, the stripping treatment for organic ligands, which is not only complex but also has destructive influence on the quality of films, is traditionally used for achieving good performance. Here, we select high crystalline oleic acid-capped SnO2 NCs to prepare ETLs with low-temperature solution-processed methodology without complex ligand stripping step. We use Nb[Formula: see text] doping route to further enhance photovoltaic performance of the planar PSCs. The champion PSC based on Nb-doped SnO2 NCs ETL achieves a power conversion efficiency of 20.07%.

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Dilshod, Nematov, Kholmurodov Kholmirzo, Stanchik Aliona, Fayzullaev Kahramon, Gnatovskaya Viktoriya, and Kudzoev Tamerlan. "On the Optical Properties of the Cu2ZnSn[S1−xSex]4 System in the IR Range." Trends in Sciences 20, no. 2 (November 29, 2022): 4058. http://dx.doi.org/10.48048/tis.2023.4058.

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Following the recent classification by the European Commission of some elements as critical raw materials (CRM), there is an increasing interest in the development of CRM-free thin film photovoltaic (PV) technologies, including kesterite materials. Moreover, starting with the performance breakthrough reported by IBM in 2010, the efficiency of kesterite-based solar cells steadily progressed in the following years achieving. Therefore, in recent years, there has been a significant research effort to develop kesterite-based devices. However, despite the large number of theoretical and experimental works, many aspects of the problem have not yet been fully studied. Therefore, the issues considered in the article, especially the behavior of the absorption and photoconductivity spectra of the Cu2ZnSn[S1−xSex]4 system, depending on the S/Se ratio, are extremely important and, at the same time, one of the topical and poorly studied problems. In this work, using quantum-chemical calculations in the framework of density functional theory (DFT), we study the optical properties of semiconductor nanocrystals of kesterite Cu2ZnSnS4 doped with Se. Using the WIEN2k package, the concentration dependences of the optical characteristics of nanocrystals of the Cu2ZnSn[S1−xSex]4 system (x = 0.00, 0.25, 0.50, 0.75 and 1.00) were calculated. It is shown that doping with Se at the S position leads to a noticeable improvement in the photoabsorbing properties of these nanocrystals, as well as their photoconductivity in the IR range. The calculated absorption and extinction spectra, as well as the refractive indices and permittivity of the materials under study, are compared with experimental data known from the literature. The data obtained will significantly enrich the existing knowledge about the materials under study and will contribute to the expansion of the field of application of these compounds in optoelectronic devices. HIGHLIGHTS With an increase in the Se concentration, the absorbing properties and photoconductivity of the nanocrystals of the Cu2ZnSn[S1−xSex]4 system increase The optical band gap narrows with increasing Se/S ratio Curves k(ω) and α (ω) correspond to the maxima of e2 (w) Pure Cu2ZnSnSe4 has the maximum absorption in the IR range GRAPHICAL ABSTRACT

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14

Резник, И. А., А. С. Златов, П. О. Ильин, Р. A. Заколдаев, С. A. Мошкалёв, and A. O. Орлова. "Люминесцентные и фотоэлектрические свойства гибридных структур на основе многослойного графена и 0D и 2D полупроводниковых квантовых нанокристаллов." Журнал технической физики 128, no. 6 (2020): 726. http://dx.doi.org/10.21883/os.2020.06.49403.66-20.

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Establishing the laws of the mechanisms underlying the interaction of nanostructured materials is one of the most important tasks on the way to creating a new generation of efficient photovoltaic devices. In this paper, we study the luminescent and photoelectric properties of hybrid structures formed on the basis of multilayer graphene nanobelts and semiconductor quantum nanocrystals: 0D-: core-shell CdSe / ZnS quantum dots, and 2D-: CdSe nanoplatelets. It was shown that the multiexponential decay of the excitonic luminescence of CdSe nanoplates at room temperature originates from the delayed luminescence due to the presence of trap states on the surface of the nanoplates. It has been established that in the dry layers of nanoplatelets on a dielectric substrate and in the composition of hybrid structures with graphene nanoribbons, the efficiency of delayed excitonic luminescence of nanoplates increases. It has been demonstrated that the rate of increase in photoconductivity in hybrid structures based on CdSe nanoplatelets is an order of magnitude higher than the rate of this process in similar structures based on CdSe / ZnS quantum dots, which indicates the formation of an effective energy / charge transfer channel from nanoplatelets to graphene nanoribbons.

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Luo, Kaiying, Wanhua Wu, Sihang Xie, Yasi Jiang, Shengzu Liao, and Donghuan Qin. "Building Solar Cells from Nanocrystal Inks." Applied Sciences 9, no. 9 (May 8, 2019): 1885. http://dx.doi.org/10.3390/app9091885.

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The use of solution-processed photovoltaics is a low cost, low material-consuming way to harvest abundant solar energy. Organic semiconductors based on perovskite or colloidal quantum dot photovoltaics have been well developed in recent years; however, stability is still an important issue for these photovoltaic devices. By combining solution processing, chemical treatment, and sintering technology, compact and efficient CdTe nanocrystal (NC) solar cells can be fabricated with high stability by optimizing the architecture of devices. Here, we review the progress on solution-processed CdTe NC-based photovoltaics. We focus particularly on NC materials and the design of devices that provide a good p–n junction quality, a graded bandgap for extending the spectrum response, and interface engineering to decrease carrier recombination. We summarize the progress in this field and give some insight into device processing, including element doping, new hole transport material application, and the design of new devices.

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Corrêa, Cinthia, Mariana Klementová, and Lukáš Palatinus. "Structural analysis of Ni3Si2by EDT and dynamical refinement." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C372. http://dx.doi.org/10.1107/s2053273314096272.

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Transition metal silicides are known for properties such as low resistivity, high melting point, low cost and low toxicity, which are of great interest for applications in current silicon nanotechnology such as nano-complementary metal-oxide semiconductor (CMOS) devices, photovoltaics and ohmic contacts. In all these technologies the materials are used on nanoscale. To gain better insight into their properties, it is necessary to be able to determine the structure of the nanoparticles of these materials. Electron diffraction tomography combined with the precession electron diffraction (PED) are ideal techniques for structural analysis of nanocrystals. In this work Ni3Si2 nanowires with diameter of 25 nm were analyzed by EDT both with and without PED. The structure was refined using the kinematical and dynamical diffraction theory. The results show that the best results can be obtained of EDT and PED.

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Camellini, Andrea, Haiguang Zhao, Sergio Brovelli, Ranjani Viswanatha, Alberto Vomiero, and Margherita Zavelani-Rossi. "(Invited) Ultrafast Spectroscopy in Semiconductor Nanocrystals: Revealing the Origin of Single Vs Double Emission, of Optical Gain and the Role of Dopants." ECS Meeting Abstracts MA2022-01, no. 20 (July 7, 2022): 1104. http://dx.doi.org/10.1149/ma2022-01201104mtgabs.

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A wide variety of materials with nanometre dimensions are increasingly explored for photonic applications. Among them, semiconductor nanocrystals (NCs) are very promising for a variety of uses, including light emission devices (LEDs), lasers, detectors, photovoltaic cells, biological labelling and sensing [1]. Key advantage of NCs is the possibility to tailor their optical response by controlling the electronic structure (“wave function engineering”) through the choice of composition, size and shape. Significant and interesting results have been obtained with heterostructured and doped NCs. Beyond single wavelength tuneable band-edge emission, other regimes have been demonstrated such as intragap emission, simultaneous emission on two different wavelengths, amplified spontaneous emission and laser emission. The luminescent properties are governed by exciton decay, which can proceed through radiative or nonradiative pathways, following different routes. The study of exciton dynamics can allow elucidating the processes connected to single or dual emission and to optical gain. This, in turn, can lead to the identification of the functional and structural characteristics that are responsible for these behaviors. Exciton relaxation occurs on picosecond timescales, so ultrafast optical techniques are required to perform these studies. In this talk, we present studies carried out by ultrafast pump-probe spectroscopy technique, with 100-fs time resolution, on CdSe/CdS and PbS/CdS heterostructured NCs, with different geometries (core/shell, dot-in-rod, dot-in-bulk, with sharp or graded interface) [2-6] and CdSeS and CdZnSe doped NCs [7,8]. These NCs are optically active in the visible and near-infrared spectral region, show single and dual colour photoluminescence emission, optical gain, laser emission and intragap emission [2-9]. The analysis of the experimental data allowed us to unravel the decay processes: the initials take place in a few ps, leading to the ultimate emitting state whose lifetime can extend to hundreds of ps to few ns, allowing for efficient luminescence and optical gain. Our data on heterostructures allowed us to clarify the role of the volume and of the shape of the outer component and the effect of the interface [2-4]. We found that dual emission is possible for both thick and thin quantum-confined shells, and for different interfaces. We studied the decoupling of excitons lying in the two different component of the NC (core exciton and shell exciton) and we revealed the evolution of the exciton barrier known as dynamic hole-blockade effect. We showed that these phenomena are strictly connected to dual emission and optical gain and we identified the condition for their maximum efficiency, in term of band alignment and band transitions. Our results provide a comprehensive understanding of the physical phenomena governing dual-emission mechanisms, suppression of Auger recombination, optical gain and laser emission in heterostructured NCs. Experiments on CdZnSe NCs doped with Mn and on CdSeS NCs engineered with sulfur vacancies, enabled us to disclose donor and acceptor localized states in the band gap. We observed the carrier dynamics responsible for intragap emission which is associated to the emergence of a transient Mn3+ state [7], in the first case, and to a donor state below the conduction band introduced by sulfur vacancies [8], in the latter case. In conclusion, the study of the exciton dynamics in different NCs allowed us to elucidate the relation between structural-morphological characteristics (shape, volume, and interface) and unconventional emission capabilities (dual emission and optical gain) in heterostructures and the photophysics of electronic states introduced by doping. This knowledge is very important to control NC functionalities toward new multilevel electronic or photonic schemes and in applications such as lasers [9], photoelectrochemical (PEC) cell [10], white light emission [11], ratiometric sensing [12]. [1] P. V. Kamat and G. D. Scholes, J. Phys. Chem. Lett. 7, 584 (2016) [2] G. Sirigu et al., Phys. Rev. B 96, 155303 (2017) [3] V. Pinchetti et al., ACS Nano 10, 6877-6887 (2016) [4] H. Zhao et al., Nanoscale 8, 4217-4226 (2016) [5] M. Zavelani-Rossi et al., Nano Lett. 10, 3142-3150 (2010) [6] R. Krahne et al., Appl. Phys. Lett. 98, 063105 (2011) [7] K. Gahlot et al., ACS Energy Lett. 4, 729−735 (2019) [8] F. Carulli et al., Nano Lett. 21, 6211−6219 (2021) [9] M. Zavelani-Rossi et al., Laser & Photonics Reviews 6, 678-683 (2012) [10] L. Jin et al., Nano Energy 30, 531-541 (2016) [11] S. Sapra et al., Adv. Mater. 19, 569 (2007) [12] J. Liu et al., ACS Photonics, 2479 (2019)

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Xiao, Kening, Qichuan Huang, Jia Luo, Huansong Tang, Ao Xu, Pu Wang, Hao Ren, Donghuan Qin, Wei Xu, and Dan Wang. "Efficient Nanocrystal Photovoltaics via Blade Coating Active Layer." Nanomaterials 11, no. 6 (June 9, 2021): 1522. http://dx.doi.org/10.3390/nano11061522.

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CdTe semiconductor nanocrystal (NC) solar cells have attracted much attention in recent year due to their low-cost solution fabrication process. However, there are still few reports about the fabrication of large area NC solar cells under ambient conditions. Aiming to push CdTe NC solar cells one step forward to the industry, this study used a novel blade coating technique to fabricate CdTe NC solar cells with different areas (0.16, 0.3, 0.5 cm2) under ambient conditions. By optimizing the deposition parameters of the CdTe NC’s active layer, the power conversion efficiency (PCE) of NC solar cells showed a large improvement. Compared to the conventional spin-coated device, a lower post-treatment temperature is required by blade coated NC solar cells. Under the optimal deposition conditions, the NC solar cells with 0.16, 0.3, and 0.5 cm2 areas exhibited PCEs of 3.58, 2.82, and 1.93%, respectively. More importantly, the NC solar cells fabricated via the blading technique showed high stability where almost no efficiency degradation appeared after keeping the devices under ambient conditions for over 18 days. This is promising for low-cost, roll-by-roll, and large area industrial fabrication.

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Yeh, P. H., L. J. Chen, P. T. Liu, D. Y. Wang, and T. C. Chang. "Nonvolatile Memory Devices with NiSi2/CoSi2 Nanocrystals." Journal of Nanoscience and Nanotechnology 7, no. 1 (January 1, 2007): 339–43. http://dx.doi.org/10.1166/jnn.2007.18032.

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Metal-oxide-semiconductor structures with NiSi2 and CoSi2 nanocrystals embedded in the SiO2 layer have been fabricated. A pronounced capacitance–voltage hysteresis was observed with a memory window about 1 V under low programming voltage. The retention characteristic can be improved by using HfO2 layer as control oxide. The processing of the structure is compatible with the current manufacturing technology of semiconductor industry.

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Kriegel, Ilka, and Francesco Scotognella. "Tunable light filtering by a Bragg mirror/heavily doped semiconducting nanocrystal composite." Beilstein Journal of Nanotechnology 6 (January 16, 2015): 193–200. http://dx.doi.org/10.3762/bjnano.6.18.

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Tunable light filters are critical components for many optical applications in which light in-coupling, out-coupling or rejection is crucial, such as lasing, sensing, photovoltaics and information and communication technology. For this purpose, Bragg mirrors (band-pass filters with high reflectivity) represent good candidates. However, their optical characteristics are determined during the fabrication stage. Heavily doped semiconductor nanocrystals (NCs), on the other hand, deliver a high degree of optical tunability through the active modulation of their carrier density, ultimately influencing their plasmonic absorption properties. Here, we propose the design of an actively tunable light filter composed of a Bragg mirror and a layer of plasmonic semiconductor NCs. We demonstrate that the filtering properties of the coupled device can be tuned to cover a wide range of frequencies from the visible to the near infrared (vis–NIR) spectral region when employing varying carrier densities. As the tunable component, we implemented a dispersion of copper selenide (Cu2−xSe) NCs and a film of indium tin oxide (ITO) NCs, which are known to show optical tunablility with chemical or electrochemical treatments. We utilized the Mie theory to describe the carrier-dependent plasmonic properties of the Cu2−x Se NC dispersion and the effective medium theory to describe the optical characteristics of the ITO film. The transmission properties of the Bragg mirror have been modelled with the transfer matrix method. We foresee ease of experimental realization of the coupled device, where filtering modulation is achieved upon chemical and electrochemical post-fabrication treatment of the heavily doped semiconductor NC component, eventually resulting in tunable transmission properties of the coupled device.

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Liu, Yanshan, Li Wang, and Yong Cao. "Photovoltaic devices from CdSe nanocrystals and conjugated polymer composites." Frontiers of Chemistry in China 2, no. 4 (October 2007): 383–86. http://dx.doi.org/10.1007/s11458-007-0072-x.

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Heben, Michael J., Amit Kumar, Chong Zheng, and Nathan S. Lewis. "Efficient photovoltaic devices for InP semiconductor/liqud junctions." Nature 340, no. 6235 (August 1989): 621–23. http://dx.doi.org/10.1038/340621a0.

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23

Gratzel, M., K. Brooks, and A. J. McEvoy. "ChemInform Abstract: Dye-Sensitized Nanocrystalline Semiconductor Photovoltaic Devices." ChemInform 31, no. 8 (June 10, 2010): no. http://dx.doi.org/10.1002/chin.200008278.

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Horváth, Zs J., and P. Basa. "Nanocrystal Non-Volatile Memory Devices." Materials Science Forum 609 (January 2009): 1–9. http://dx.doi.org/10.4028/www.scientific.net/msf.609.1.

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The physical background and present status of the application of metal-insulator-silicon structures with semiconductor nanocrystals embedded in the insulator layer for memory purposes is breafly summarized.

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Xie, Sihang, Xueqi Li, Yasi Jiang, Rourou Yang, Muyi Fu, Wanwan Li, Yiyang Pan, Donghuan Qin, Wei Xu, and Lintao Hou. "Recent Progress in Hybrid Solar Cells Based on Solution-Processed Organic and Semiconductor Nanocrystal: Perspectives on Device Design." Applied Sciences 10, no. 12 (June 22, 2020): 4285. http://dx.doi.org/10.3390/app10124285.

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Solution-processed hybrid solar cells have been well developed in the last twenty years due to the advantages of low cost, low material-consuming and simple fabricating technology. However, the performance, stability and film quality of hybrid solar cells need to be further improved for future commercial application (with a lifetime up to 20 years and power conversion efficiency higher than 15%). By combining the merits of organic polymers and nanocrystals (NC), the reasonable design of interface engineering and device architecture, the performance coupled with stability of hybrid solar cells can be significantly improved. This review gives a brief conclusive introduction to the progress on solution-processed organic/inorganic semiconductor hybrid solar cells, including a summary of the development of hybrid solar cells in recent years, the strategy of hybrid solar cells with different structures and the incorporation of new organic hole transport materials with new insight into device processing for high efficiency. This paper also puts forward some suggestions and guidance for the future development of high-performance NC-based photovoltaics.

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Mashreki, Tarek I. A., and Mohammad Afzaal. "Nanocrystalline Materials for Hybrid Photovoltaic Devices." Advanced Materials Research 1116 (July 2015): 45–50. http://dx.doi.org/10.4028/www.scientific.net/amr.1116.45.

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Nanocomposites containing inorganic semiconductor nanomaterials are of tremendous interest for low-cost 3rd generation solar cells. A variety of possible materials and structures could be potentially used to reduce processing costs which is highly attractive for large scale production of solar cells. Controlling the morphology and surface chemistry of nanomaterials remains a key challenge that has major knock-on effects in devices. Herein, an attempt is made to highlight some of the challenges and the possible solutions for depositing high quality thin film composites for solar cell devices.

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Zhu, Xiangxiang, Zeke Liu, Guozheng Shi, Jinan Gu, Weiwei Wang, and Wanli Ma. "Photovoltaic devices employing ternary PbS x Te 1-x nanocrystals." Journal of Materials Science & Technology 33, no. 5 (May 2017): 418–23. http://dx.doi.org/10.1016/j.jmst.2017.01.018.

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Shim, Moonsub, Congjun Wang, David J. Norris, and Philippe Guyot-Sionnest. "Doping and Charging in Colloidal Semiconductor Nanocrystals." MRS Bulletin 26, no. 12 (December 2001): 1005–8. http://dx.doi.org/10.1557/mrs2001.257.

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Modern semiconductor technology has been enabled by the ability to control the number of carriers (electrons and holes) that are available in the semiconductor crystal. This control has been achieved primarily with two methods: doping, which entails the introduction of impurity atoms that contribute additional carriers into the crystal lattice; and charging, which involves the use of applied electric fields to manipulate carrier densities near an interface or junction. By controlling the carriers with these methods, the electrical properties of the semiconductor can be precisely tailored for a particular application. Accordingly, doping and charging play a major role in most modern semiconductor devices.

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Lungenschmied, C., G. Dennler, H. Neugebauer, N. S. Sariciftci, and E. Ehrenfreund. "Internal electric field in organic-semiconductor-based photovoltaic devices." Applied Physics Letters 89, no. 22 (November 27, 2006): 223519. http://dx.doi.org/10.1063/1.2398898.

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Yu, Buyang, Chunfeng Zhang, Lan Chen, Zhengyuan Qin, Xinyu Huang, Xiaoyong Wang, and Min Xiao. "Ultrafast dynamics of photoexcited carriers in perovskite semiconductor nanocrystals." Nanophotonics 10, no. 8 (June 1, 2020): 1943–65. http://dx.doi.org/10.1515/nanoph-2020-0681.

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Abstract Perovskite semiconductor nanocrystals have emerged as a promising family of materials for optoelectronic applications including light-emitting diodes, lasers, light-to-electricity convertors and quantum light emitters. The performances of these devices are fundamentally dependent on different aspects of the excited-state dynamics in nanocrystals. Herein, we summarize the recent progress on the photoinduced carrier dynamics studied by a variety of time-resolved spectroscopic methods in perovskite nanocrystals. We review the dynamics of carrier generation, recombination and transport under different excitation densities and photon energies to show the pathways that underpin the photophysics for light-emitting diodes and solar cells. Then, we highlight the up-to-date spin dynamics and coherent exciton dynamics being manifested with the exciton fine levels in perovskite semiconductor nanocrystals which are essential for potential applications in quantum information technology. We also discuss the controversial results and the possible origins yet to be resolved. In-depth study toward a comprehensive picture of the excited-state dynamics in perovskite nanocrystals may provide the key knowledge of the device operation mechanism, enlighten the direction for device optimization and stimulate the adventure of new conceptual devices.

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Roither, J., W. Heiss, N. P. Gaponik, D. V. Talapin, and A. Eychmüller. "Colloidally synthesised semiconductor nanocrystals in resonant cavity light emitting devices." Electronics Letters 38, no. 22 (2002): 1373. http://dx.doi.org/10.1049/el:20020890.

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Garcia, Emilio, Christophe Arnold, Jean-Pierre Hermier, and Michele D'Amico. "Gold plasmonic enhanced luminescence of silica encapsulated semiconductor hetero-nanoplatelets." Nanoscale Advances 3, no. 15 (2021): 4572–78. http://dx.doi.org/10.1039/d1na00273b.

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Kamat, Prashant V., Rebecca Scheidt, Geetha Balakrishna, Steven Kobosko, and Vikashkumar Ravi. "(Keynote) Photocatalytic Aspects of CsPbBr₃ Perovskite Nanocrystals." ECS Meeting Abstracts MA2018-01, no. 31 (April 13, 2018): 1842. http://dx.doi.org/10.1149/ma2018-01/31/1842.

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Lead halide perovskites have been extensively studied to explore their photovoltaic properties. They offer a useful strategy for continuous tuning of the semiconductor bandgap. In addition to photovoltaic applications these lead halide perovskites offer rich photophysical properties with ability to induce electron and hole transfer at the semiconductor/electrolyte interface. The photoinduced electron transfer between CsPbBr3 quantum dots and methyl viologen shows electron transfer to be completed with 20 ps. The transient absorption spectroscopy and emission spectroscopy offers mechanistic and kinetic insights of the interfacial charge transfer processes. CsPbBr3 films cast from colloidal suspension can also be transformed into CsPbI3 via a halide exchange reaction upon exposure to a heated PbI2 solution (~70°C). The internal structure of hybrid CsPbBrxI3-x varies with increasing thickness of the exchanged film. The gradient structure thus allows us to probe the flow of the charge carriers within the film. The electron transfer properties that highlight photocatalytic properties of mixed halide nanocrystals will be discussed.

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Handa, Taketo, Takumi Yamada, and Yoshihiko Kanemitsu. "Review—Photoluminescence Characterization of Halide Perovskite Materials and Solar Cells." ECS Journal of Solid State Science and Technology 12, no. 5 (May 1, 2023): 056004. http://dx.doi.org/10.1149/2162-8777/acd660.

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Photoluminescence spectroscopy is a powerful technique for investigating carrier dynamics in semiconductor materials and photovoltaic devices. In this short review, we present our recent luminescence spectroscopic studies on halide perovskites, including thin films and solar cell devices, and discuss their photocarrier dynamics with relevance to photovoltaic performance.

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Álvarez-Conde, Javier, Eva M. García-Frutos, and Juan Cabanillas-Gonzalez. "Organic Semiconductor Micro/Nanocrystals for Laser Applications." Molecules 26, no. 4 (February 11, 2021): 958. http://dx.doi.org/10.3390/molecules26040958.

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Organic semiconductor micro/nanocrystals (OSMCs) have attracted great attention due to their numerous advantages such us free grain boundaries, minimal defects and traps, molecular diversity, low cost, flexibility and solution processability. Due to all these characteristics, they are strong candidates for the next generation of electronic and optoelectronic devices. In this review, we present a comprehensive overview of these OSMCs, discussing molecular packing, the methods to control crystallization and their applications to the area of organic solid-state lasers. Special emphasis is given to OSMC lasers which self-assemble into geometrically defined optical resonators owing to their attractive prospects for tuning/control of light emission properties through geometrical resonator design. The most recent developments together with novel strategies for light emission tuning and effective light extraction are presented.

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36

Sulaiman, Khaulah, Zubair Ahmad, Muhamad Saipul Fakir, Fadilah Abd Wahab, Shahino Mah Abdullah, and Zurianti Abdul Rahman. "Organic Semiconductors: Applications in Solar Photovoltaic and Sensor Devices." Materials Science Forum 737 (January 2013): 126–32. http://dx.doi.org/10.4028/www.scientific.net/msf.737.126.

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Organic semiconductor-based solar photovoltaic cells and sensors are scalable, printable, solution processable, bendable and light-weight. Furthermore, organic semiconductors require low energy fabrication process, hence can be fabricated at low cost as light-weight solar cells and sensors, coupled with the ease of processing, as well as compatibility, with flexible substrates. Organic semiconductors have been identified as a fascinating class of novel semiconductors that have the electrical and optical properties of metals and semiconductors. The continuous demand to improve the properties of organic semiconductors raises the quest for a deep understanding of fundamental issues and relevant electronic processes. Organic semiconductor thin film is sandwiched between two metal electrodes of indium tin oxide (ITO) and aluminum to form organic photovoltaic solar cell. Several types of organic semiconductors have been utilized as the photoactive layer in the solution processable organic solar cells. The performance of the fabricated solar cells can be improved by dissolving the material in the right choice of solvent, annealing of organic thin film, slowly forming the thin film and introducing an infra-red absorbance layer. Besides, organic semiconductor-based sensors can be fabricated utilizing either in a sandwidch type or planar type device. Some of these techniques and the experimental results are presented.

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Wang, Jian, Yun-Ju Lee, and Julia W. P. Hsu. "Sub-10 nm copper chromium oxide nanocrystals as a solution processed p-type hole transport layer for organic photovoltaics." Journal of Materials Chemistry C 4, no. 16 (2016): 3607–13. http://dx.doi.org/10.1039/c6tc00541a.

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Fluieraru, Cristian-Petre, Gabriel Predușcă, Horia Andrei, Emil Diaconu, Petru Adrian Cotfas, and Daniel Tudor Cotfas. "Determination of Technological Features of a Solar Photovoltaic Cell Made of Monocrystalline Silicon P+PNN+." International Journal of Photoenergy 2019 (November 19, 2019): 1–14. http://dx.doi.org/10.1155/2019/7945683.

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The development in the field of semiconductor materials and electronic devices has a great impact on systems with renewable energy sources. Determination of the functional parameters of photovoltaic solar cells is essential for the subsequent usage of these semiconductor devices. Research was made on type P+PNN+ monocrystalline silicon wafers. Crystallographic measurements of the photovoltaic solar cell were made by means of FESEM-FIB Auriga Workstation. Initial data were selected from the study of models found in the specialized literature. The experimental results were compared to classical mathematical models. Measurements made on the photovoltaic solar cell were realised in laboratory conditions on the NI-ELVIS platform produced by National Instruments.

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Krivoshlykov, Sergei G., and Valery I. Rupasov. "Photovoltaic effect in semiconductor nanocrystals embedded into amorphous silicon p-n junction." Applied Physics Letters 93, no. 4 (July 28, 2008): 043116. http://dx.doi.org/10.1063/1.2958235.

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40

Panchekha, P. A. "Structure and Technology Problems of Semiconductor Film for Photovoltaic Devices." Telecommunications and Radio Engineering 55, no. 4 (2001): 6. http://dx.doi.org/10.1615/telecomradeng.v55.i4.90.

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41

Yang Biao, Liu Xiang-Xin, and Li Hui. "History and latest development of ferroelectric-semiconductor coupled photovoltaic devices." Acta Physica Sinica 64, no. 3 (2015): 038807. http://dx.doi.org/10.7498/aps.64.038807.

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Leţ, D., V. Cimpoca, A. Stancu, C. Fluieraru, and Z. Bacinschi. "Si Photovoltaic Semiconductor Devices Operating in Total and Partial Illumination." Acta Physica Polonica A 121, no. 1 (January 2012): 65–67. http://dx.doi.org/10.12693/aphyspola.121.65.

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Batke, E., J. Kaminsky, J. P. Kotthaus, and J. Spector. "Tunable far‐infrared photovoltaic response in semiconductor field‐effect devices." Applied Physics Letters 54, no. 2 (January 9, 1989): 131–33. http://dx.doi.org/10.1063/1.101206.

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44

Navarro Arenas, Juan, Ananthakumar Soosaimanickam, Hamid Pashaei Adl, Rafael Abargues, Pablo P. Boix, Pedro J. Rodríguez-Cantó, and Juan P. Martínez-Pastor. "Ligand-Length Modification in CsPbBr3 Perovskite Nanocrystals and Bilayers with PbS Quantum Dots for Improved Photodetection Performance." Nanomaterials 10, no. 7 (July 2, 2020): 1297. http://dx.doi.org/10.3390/nano10071297.

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Nanocrystals surface chemistry engineering offers a direct approach to tune charge carrier dynamics in nanocrystals-based photodetectors. For this purpose, we have investigated the effects of altering the surface chemistry of thin films of CsPbBr3 perovskite nanocrystals produced by the doctor blading technique, via solid state ligand-exchange using 3-mercaptopropionic acid (MPA). The electrical and electro-optical properties of photovoltaic and photoconductor devices were improved after the MPA ligand exchange, mainly because of a mobility increase up to 5 × 10−3 cm 2 / Vs . The same technology was developed to build a tandem photovoltaic device based on a bilayer of PbS quantum dots (QDs) and CsPbBr3 perovskite nanocrystals. Here, the ligand exchange was successfully carried out in a single step after the deposition of these two layers. The photodetector device showed responsivities around 40 and 20 mA/W at visible and near infrared wavelengths, respectively. This strategy can be of interest for future visible-NIR cameras, optical sensors, or receivers in photonic devices for future Internet-of-Things technology.

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Bain, Dipankar, Bipattaran Paramanik, Suparna Sadhu, and Amitava Patra. "A study into the role of surface capping on energy transfer in metal cluster–semiconductor nanocomposites." Nanoscale 7, no. 48 (2015): 20697–708. http://dx.doi.org/10.1039/c5nr06793f.

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Metal cluster–semiconductor nanocomposite materials remain a frontier area of research for the development of optoelectronic, photovoltaic and light harvesting devices because metal nanoclusters and semiconductor QDs are promising candidates for photon harvesting.

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46

Ji, Chao, Tuo Li, Xiaofeng Zou, and Lu Zhang. "Transport Layer Optimization Strategy to Prepare High Efficiency Perovskite Photovoltaic Device." Journal of Physics: Conference Series 2356, no. 1 (October 1, 2022): 012020. http://dx.doi.org/10.1088/1742-6596/2356/1/012020.

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Perovskite photovoltaic devices have attracted widespread attention. Despite the spectacular advances in power conversion efficiency (PCE), the unsatisfying stability of the perovskite devices is still a great challenge, which requires a deeper understanding of the device physics, in particular, the interfacial behavior and the junction structure of the perovskite semiconductor devices. Here we demonstrate the continuous decrease of ionic interface charge (IIC) density, weakening of current-voltage hysteresis, decrease of leakage current as well as constant increase of PCE from ~10% to ~19% were achieved through step-by-step modification of the hole transport layer (HTL) and electron transport layer (ETL) of the devices. A new semiconductor device junction device model is presented to understand the correlation between the IIC density and the photovoltaic performance. The work shows that although the IIC is originated from mobile ions in perovskite layer, the IIC density is determined by the properties of the charge transport layer. These conclusions and the proposed device model have important implication for future study in pursuing efficient and stable perovskite photovoltaic devices.

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Friend, Richard. "Organic Materials for Large Area Electronics." Materials Science Forum 608 (December 2008): 159–79. http://dx.doi.org/10.4028/www.scientific.net/msf.608.159.

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Organic materials have been developed to operate as the active semiconductor in a wide range of semiconductor devices, including light-emitting diodes, LEDs, field-effect transistors, FETs, and photovoltaic diodes, PVs. The ability to process these materials as thin films over large areas makes possible a range of applications, currently in displays, as LEDs and as active matrix FET arrays, and solar cells. This article reviews developments in semiconductor physics of these materials and in their application in semiconductor devices

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Hoang, Son, Ahsan Ashraf, Matthew D. Eisaman, Dmytro Nykypanchuk, and Chang-Yong Nam. "Enhanced photovoltaic performance of ultrathin Si solar cells via semiconductor nanocrystal sensitization: energy transfer vs. optical coupling effects." Nanoscale 8, no. 11 (2016): 5873–83. http://dx.doi.org/10.1039/c5nr07932b.

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Das, K., S. Maikap, A. Dhar, B. K. Mathur, and S. K. Ray. "Metal-oxide-semiconductor structure with Ge nanocrystals for memory devices applications." Electronics Letters 39, no. 25 (2003): 1865. http://dx.doi.org/10.1049/el:20031146.

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Jun, Shinae, Eunjoo Jang, Jongjin Park, and Jongmin Kim. "Photopatterned Semiconductor Nanocrystals and Their Electroluminescence from Hybrid Light-Emitting Devices." Langmuir 22, no. 6 (March 2006): 2407–10. http://dx.doi.org/10.1021/la051756k.

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