Journal articles: 'Graphene-Surfactant Interactions'

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Liu, Ming Xian, Zhi Xin Jia, and Chang Ren Zhou. "Dispersion of Single-Walled Carbon Nanotubes in Water by a Conjugated Surfactant." Advanced Materials Research 415-417 (December 2011): 562–65. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.562.

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Stable water dispersions of single wall carbon nanotubes (SWCNTs) have important implications for their applications in biomedical and composites field. In this work, a water-soluble optical brightener bearing benzene ring and sodium sulfonate groups was employed as surfactant for SWCNTs in water. The surfactant molecules were absorbed on graphene nanotube surfaces via π-π interaction, Van Der Waals interaction and electrostatic interactions in water under ultrasonic treatment. The functionalized carbon nanotubes were stably dispersed in water for several months without sedimentation. The carbon nanotubes/organic conjugated molecules nanohybrids have potential application in nanocomposites, biomedical engineering, and photovoltaic devices.

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Kim, Ho Shin, Nathanael A. Brown, Stefan Zauscher, and Yaroslava G. Yingling. "Effect of Octadecylamine Surfactant on DNA Interactions with Graphene Surfaces." Langmuir 36, no. 4 (January 9, 2020): 931–38. http://dx.doi.org/10.1021/acs.langmuir.9b02926.

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Kim, Hye-soo, Stephanie Lee, Mei Wang, Junmo Kang, Yan Sun, Jae Jung, Kyunghoon Kim, Sung-Min Kim, Jae-Do Nam, and Jonghwan Suhr. "Experimental Investigation on 3D Graphene-CNT Hybrid Foams with Different Interactions." Nanomaterials 8, no. 9 (September 6, 2018): 694. http://dx.doi.org/10.3390/nano8090694.

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Due to the exceptional properties of graphene, numerous possibilities for real applications in various fields have been provided. However, it is a challenge to fabricate bulk graphene materials with properties arising from the nature of individual graphene sheets, and which assemble into monolithic three-dimensional structures. If 3D structured graphene foam were made instead of 2D structured graphene, it is expected that it would be a facile fabrication, with relatively low cost with the possibility of scale-up, and would maintain the intrinsic properties of graphene. To solve the weaknesses of 2D structured graphene, this study aimed to fabricate a 3D graphene-carbon nanotubes (CNT) hybrid foam. In this study, CNT was used to reinforce the graphene foams. In addition, two different surfactants, known as sodium dodecylbenzene sulphonate (SDBS) and cetyltrimethylammonium bromide (CTAB), were applied to help CNT dispersion. The π–π interaction was induced by SDBS/CNT, while ionic interaction was derived from CTAB/CNT. To confirm the charge effect with different surfactants, SEM, Zeta-potential, FT-IR, Raman spectroscopy, and compression tests were performed. When using a cationic surfactant, CTAB, compressive modulus, and strength increased due to the formation of relatively strong ionic bonding.

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Shih, Chih-Jen, Geraldine L. C. Paulus, Qing Hua Wang, Zhong Jin, Daniel Blankschtein, and Michael S. Strano. "Understanding Surfactant/Graphene Interactions Using a Graphene Field Effect Transistor: Relating Molecular Structure to Hysteresis and Carrier Mobility." Langmuir 28, no. 22 (May 23, 2012): 8579–86. http://dx.doi.org/10.1021/la3008816.

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Lin, Jing, Xiansong Wang, Guangxia Shen, and Daxiang Cui. "3D Plasmonic Ensembles of Graphene Oxide and Nobel Metal Nanoparticles with Ultrahigh SERS Activity and Sensitivity." Journal of Nanomaterials 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/7689357.

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We describe a comparison study on 3D ensembles of graphene oxide (GO) and metal nanoparticles (silver nanoparticles (AgNPs), gold nanoparticles (GNPs), and gold nanorods (GNRs)) for surface-enhanced Raman scattering (SERS) application. For the first time, GNRs were successfully assembled on the surfaces of GO by means of electrostatic interactions without adding any surfactant. The SERS properties of GO/AgNPs, GO/GNPs, and GO/GNRs were compared using 2-mercaptopyridine (2-Mpy) as probing molecule. We found that GO/AgNPs and GO/GNPs substrates are not suitable for detecting 2-Mpy due to the very strongπ-πstacking interaction between the 2-Mpy molecules andsp2carbon structure of GO. Conversely, the GO/GNRs substrates show ultrahigh SERS activity and sensitivity of 2-Mpy with the detection limit as low as ~10-15 M, which is ~2-3 orders of magnitude higher than that of the corresponding GNRs.

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Arunachalam, Vaishali, and Sukumaran Vasudevan. "Probing Graphene–Surfactant Interactions in Aqueous Dispersions with Nuclear Overhauser Effect NMR Spectroscopy and Molecular Dynamics Simulations." Journal of Physical Chemistry C 121, no. 30 (July 19, 2017): 16637–43. http://dx.doi.org/10.1021/acs.jpcc.7b05404.

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Lashkari, Sima, Sima A. Lashkari, and Rajinder Pal. "Ionic Liquid/Non-Ionic Surfactant Mixtures As Versatile, Non-Volatile Electrolytes: Double-Layer Capacitance and Conductivity." ECS Meeting Abstracts MA2022-01, no. 1 (July 7, 2022): 5. http://dx.doi.org/10.1149/ma2022-0115mtgabs.

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Self-assembly of ionic liquids (ILs) on 2D materials such as graphene oxide and MXenes facilitated by non-ionic surfactants is a promising approach being increasingly used for the fabrication of high surface area electrodes resulting in high performance supercapacitors. However, the impact that non-ionic surfactants have on double-layer formation and ionic conductivity has yet to be explored. These surfactants are not ionically conductive, have low dielectric constants and high viscosity which are expected to impact the final performance of the electrode. In this study we analyze the effect of adding two commonly used non-ionic surfactants, P123 and Triton X-100 (TX-100) to 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMImTFSI) on the double-layer capacitance formed at a glassy carbon electrode by means of electrochemical impedance spectroscopy. The results, surprisingly suggest an improvement of 75% and 116% in the double layer capacitance measured at the open circuit voltage for 40% of P123 and TX-100, respectively. We also interpret the changes in the DC potential dependence of the capacitance via the most up-to-date understanding of double-layer charging mechanisms with ionic liquids. Similar to previous literature on solvent-based diluents such as polycarbonate and acetonitrile, which cause a similar effect, the improved capacitance is attributed to the reduced Debye length resulting from an increased effective ionic charge accrued by the IL when surrounded by the low-dielectric constant surfactant. Both electrolyte series show the same reduction in ionic conductivity (from 8.5 mS/cm to 1 mS/cm) with respect to concentration regardless of the higher viscosity measured for the P123 electrolyte series. Pulsed field gradient nuclear magnetic resonance, is used to determine the diffusion coefficient for the IL as a function of surfactant concentration and allow us to calculate the effective Stokes radius which is found to shrink significantly as a function of surfactant concentration. Similar to the improved capacitance, this is caused by a reduction in ion-ion interactions and an increase in the average effective charge on each ion. These effects make the electrolyte less sensitive than expected to the increased viscosity caused by addition of the more viscous surfactant phase. The ability to improve the capacitance with non-volatile, low dielectric constant additives, without significantly sacrificing ionic conductivity, opens up an improved avenue for completely non-volatile, non-flammable electrolyte design.

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Walch, Nik J., Alexei Nabok, Frank Davis, and Séamus P. J. Higson. "Characterisation of thin films of graphene–surfactant composites produced through a novel semi-automated method." Beilstein Journal of Nanotechnology 7 (February 8, 2016): 209–19. http://dx.doi.org/10.3762/bjnano.7.19.

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In this paper we detail a novel semi-automated method for the production of graphene by sonochemical exfoliation of graphite in the presence of ionic surfactants, e.g., sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB). The formation of individual graphene flakes was confirmed by Raman spectroscopy, while the interaction of graphene with surfactants was proven by NMR spectroscopy. The resulting graphene–surfactant composite material formed a stable suspension in water and some organic solvents, such as chloroform. Graphene thin films were then produced using Langmuir–Blodgett (LB) or electrostatic layer-by-layer (LbL) deposition techniques. The composition and morphology of the films produced was studied with SEM/EDX and AFM. The best results in terms of adhesion and surface coverage were achieved using LbL deposition of graphene(−)SDS alternated with polyethyleneimine (PEI). The optical study of graphene thin films deposited on different substrates was carried out using UV–vis absorption spectroscopy and spectroscopic ellipsometry. A particular focus was on studying graphene layers deposited on gold-coated glass using a method of total internal reflection ellipsometry (TIRE) which revealed the enhancement of the surface plasmon resonance in thin gold films by depositing graphene layers.

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Chen, Xuanlai, Guochao Yan, Xianglin Yang, Guang Xu, and Shuai Wei. "Microscopic Diffusion Characteristics of Linear Alkylbenzene Sulfonates on the Surface of Anthracite: The Influence of Different Attachment Sites of Benzene Ring in the Backbone." Minerals 11, no. 10 (September 27, 2021): 1045. http://dx.doi.org/10.3390/min11101045.

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In order to explore the effect of the attachment site of the benzene ring in the backbone of the surfactant on its diffusion characteristics on the surface of anthracite, the molecular dynamics simulation method was used, and the four isomers (m-C16, m = 2,4,6,8; m represents the attachment site of the benzene ring in the backbone) of sodium hexadecyl benzene sulfonate (SHS) were selected. Binary models of surfactant/anthracite, surfactant/graphene modified by oxygen-containing functional groups, and a ternary model of water/surfactant/anthracite were constructed. By analyzing a series of properties such as interaction energy, contact surface area, relative concentration distribution, radial distribution function, hydrophobic tail chain order parameter, etc., it is concluded that the adsorption strength of 4-C16 on the surface of anthracite is the highest; the reason is that 4-C16 has the highest degree of aggregation near the oxygen-containing functional groups on the surface of anthracite. Further investigations find that 4-C16 can be densely covered on the ketone group, and the longer branch chain of 4-C16 has the highest degree of order in the Z-axis direction.

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Li, Liangchuan, Ming Zhou, Long Jin, Youtang Mo, Enyong Xu, Huajin Chen, Lincong Liu, Mingyue Wang, Xin Chen, and Hongwei Zhu. "Green Preparation of Aqueous Graphene Dispersion and Study on Its Dispersion Stability." Materials 13, no. 18 (September 14, 2020): 4069. http://dx.doi.org/10.3390/ma13184069.

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The large-scale preparation of stable graphene aqueous dispersion has been a challenge in the theoretical research and industrial applications of graphene. This study determined the suitable exfoliation agent for overcoming the van der Waals force between the layers of expanded graphite sheets using the liquid-phase exfoliation method on the basis of surface energy theory to prepare a single layer of graphene. To evenly and stably disperse graphene in pure water, the dispersants were selected based on Hansen solubility parameters, namely, hydrophilicity, heterocyclic structure and easy combinative features. The graphene exfoliation grade and the dispersion stability, number of layers and defect density in the dispersion were analysed under Tyndall phenomenon using volume sedimentation method, zeta potential analysis, scanning electron microscopy, Raman spectroscopy and atomic force microscopy characterization. Subsequently, the long-chain quaternary ammonium salt cationic surfactant octadecyltrimethylammonium chloride (0.3 wt.%) was electrolyzed in pure water to form ammonium ions, which promoted hydrogen bonding in the remaining oxygen-containing groups on the surface of the stripped graphene. Forming the electrostatic steric hindrance effect to achieve the stable dispersion of graphene in water can exfoliate a minimum of eight layers of graphene nanosheets; the average number of layers was less than 14. The 0.1 wt.% (sodium dodecylbenzene sulfonate: melamine = 1:1) mixed system forms π–π interaction and hydrogen bonding with graphene in pure water, which allow the stable dispersion of graphene for 22 days without sedimentation. The findings can be beneficial for the large-scale preparation of waterborne graphene in industrial applications.

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Zeng, Xiaopeng, Jingjing Yang, Lizhen Zhang, Lijuan Chen, and Wenxia Yuan. "Homogeneous dispersion of high-conductive reduced graphene oxide sheets for polymethylmethacrylate nanocomposites." Powder Diffraction 29, no. 3 (March 3, 2014): 241–47. http://dx.doi.org/10.1017/s0885715614000050.

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The high cohesive interaction between reduced graphene oxide (RGO) sheets usually makes them difficult to disperse, which limits their utilization in achieving effective hybridization with polymers. We report here a new two-step route for preparing non-aggregated and high-conductive RGO powders. Graphene oxide precursor was first reduced by hydrazine hydrate in presence of a thermal unstable surfactant of cetyltrimethylammonium chloride (CTAC). Then a thermal annealing process under H2/Ar atmosphere was further used to remove the non-conductive CTAC molecules. The prepared RGO powder exhibited an electrical conductivity of 2.23 × 104 S m−1 – about ten times higher than the one (N-RGO) simply reduced by hydrazine hydrate. After incorporating into polymethylmethacrylate with a 5 wt% loading, the composite showed a conductivity of 4.11 S m−1, which was 60 times as high as that of the same composite based on N-RGO powder. The addition and subsequent removal of CTAC molecules is an effective method for preparing non-aggregated and highly conductive graphene powder and obtaining good incorporation into polymer matrices.

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Choi, Yeon Jun, Hyun-Kyung Kim, Suk-Woo Lee, Young Hwan Kim, Hee-Chang Youn, Kwang Chul Roh, and Kwang-Bum Kim. "Surfactant-free synthesis of a nanoperforated graphene/nitrogen-doped carbon nanotube composite for supercapacitors." Journal of Materials Chemistry A 5, no. 43 (2017): 22607–17. http://dx.doi.org/10.1039/c7ta06742a.

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Zhao, Xin, Dandan Ke, Shumin Han, Yuan Li, Hongming Zhang, and Ying Cai. "Surfactant PVA-Stabilized Co–Mo Nanocatalyst Supported by Graphene Oxide Sheets Toward the Hydrolytic Dehydrogenation of Ammonia Borane." Nano 14, no. 11 (November 2019): 1950137. http://dx.doi.org/10.1142/s1793292019501376.

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By adding surfactant polyvinyl alcohol (PVA) and controlling the preparation process, we successfully synthesized Co–Mo catalysts. For further improving the dispersion, reduced graphene oxide sheets as catalyst carrier were introduced to synthesize Co–Mo@rGO composite catalyst as highly efficient catalysts for hydrolytic dehydrogenation of ammonia borane. The introduction of Mo for preparing Co–Mo@rGO catalyst helped to form alloy catalyst with better structure, better dispersity and smaller particle size. When the molar ratio of Co and Mo was 0.75:0.25, the bimetallic composite catalyst exhibited superior activity with TOF value of 16.29[Formula: see text]mol[Formula: see text]. The activation energy of the reaction was calculated to be 43.72[Formula: see text]kJ[Formula: see text][Formula: see text]. Furthermore, the reusability tests reveal that waxberry-like Co–Mo still show good catalytic activity with 80.3% of their initial activity in five successive runs. The enhanced catalytic activities were due to the synergistic interaction between graphene sheets and waxberry-like Co–Mo NPs, which was beneficial to improve the dispersion and stability of bimetallic NPs. Also, ligand effects on the formation of waxberry-like structure and amorphous state further promoted the catalytic activity.

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Gataullin, Azat R., Svetlana A. Bogdanova, and Yuriy G. Galyametdinov. "ADSORPTION OF ETHOXYLATED ISONONYLPHENOLS ON CARBON NANOTUBES FROM AQUEOUS SOLUTIONS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 64, no. 3 (March 20, 2021): 46–51. http://dx.doi.org/10.6060/ivkkt.20216403.6192.

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One of the approaches to solving the problem of carbon nanotubes dispersions obtaining is the use of nonionic surfactants in the processes of ultrasonication of carbon nanostructures in aqueous solutions. The effect of nonionic surfactants on dispersing and stabilizing is determined by the adsorption interaction of surfactant molecules with a graphene surface, the study of which can reveal important patterns of stable carbon nanotubes dispersions obtaining during ultrasonic treatment in liquid media. The aim of this work was to study the adsorption of ethoxylated isononylphenols with a variable average degree of ethoxylation on single-walled and multi-walled carbon nanotubes from aqueous solutions. The value of adsorption of nonionic surfactants on carbon nanotubes was calculated on the basis of changes in the equilibrium concentration of ethoxylated isononylphenols in the solution at presence of carbon nanotubes. The equilibrium concentration of nonionic surfactants was determined by absorption spectroscopy. It was found that the shape of adsorption isotherms of the ethoxylated isononylphenols on carbon nanotubes from aqueous solutions before ultrasonic treatment corresponds to the Langmuir adsorption isotherm L2. The values of maximum adsorption of ethoxylated isononylphenols were shown to decrease with an increase in the average degree of ethoxylation. Obviously, this is due to conformational changes in the polar chain, showed in the sizes of ethoxylated isononylphenols micelles, in the structure of the adsorption layer. It has been established that the hydrophobic interaction of the surfactants hydrocarbon radical with a graphene surface is the main mechanism for the adsorption of ethoxylated isononylphenols on carbon nanotubes. The dispersions of carbon nanotubes in micellar solutions of nonionic surfactants were obtained and studied. It was shown that ultrasonic treatment leads to a change in the mechanism of nonionic surfactants adsorption on carbon nanotubes.

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Zhan, Yanhu, Yuchao Li, Yanyan Meng, Qian Xie, and Marino Lavorgna. "Electric Heating Behavior of Reduced Oxide Graphene/Carbon Nanotube/Natural Rubber Composites with Macro-Porous Structure and Segregated Filler Network." Polymers 12, no. 10 (October 19, 2020): 2411. http://dx.doi.org/10.3390/polym12102411.

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Conductive polymer composites with carbonaceous fillers are very attractive and play a significant role in the field of electric heaters owing to their lightweight, corrosion resistance, and easy processing as well as low manufacturing cost. In this study, lightweight reduced oxide graphene/carbon nanotube/natural rubber (rGO/CNT/NR) composites were fabricated by a facile and cost-effective approach, which consists of rGO assembling on rubber latex particles and hydrogels formation due to the interaction network established between carbonaceous fillers and subsequent mild-drying of the resulting hydrogels. Thanks to the amphiphilic nature of GO sheets, which can serve as a surfactant, the hydrophobic CNTs were easily dispersed into water under ultrasound. On the basis of both the high stable rGO and CNTs suspension and the assembling of rGO on rubber latex, a three-dimensional segregated network of CNT and rGO were easily constructed in macro-porous composites. Either the segregated network and macro-porous structure endowed the resulting composites with low density (0.45 g cm−3), high electrical conductivity (0.60 S m−1), and excellent electric heating behavior, when the weight content of rGO and CNTs are 0.5% and 2.5%, respectively. For electric heating behavior, the steady-state temperature of the above composites reaches 69.1 °C at an input voltage of 15 V.

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Wang, Fang, Wei Sha, Xin Wang, Yuntao Shang, Lei Hou, and Yao Li. "Adsorption of 17α-Ethinyl Estradiol and Bisphenol A to Graphene-Based Materials: Effects of Configuration of Adsorbates and the Presence of Cationic Surfactant." Adsorption Science & Technology 2021 (April 20, 2021): 1–12. http://dx.doi.org/10.1155/2021/9970268.

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Endocrine-disrupting chemicals (EDCs) have attracted much attention in recent years. Graphene-based materials (GMs) have been deemed as excellent adsorbents for the removal of EDCs. The objective of the present study was to understand how the cationic surfactants (CTAB; cetyltrimethylammonium nitrate) affect the adsorption of EDCs (17α-ethinyl estradiol (EE2) and bisphenol A (BPA)) on graphene oxide (GO), reduced graphene oxides (RGOs), and the few-layered commercial graphene (CG). It was observed that the presence of CTAB showed different effects on the adsorption of EDCs to different GMs. The adsorption of EDCs on GO was enhanced because of the enhanced hydrophobicity of GMs after the adsorption of CTAB and the newly formed hemimicelles by the adsorbed CTAB, which could serve as the partition phase for EDCs. Moreover, the electron donor-acceptor interaction and cation bridging effect of the –NH4+ group of the adsorbed CTAB between EDCs and GMs could also enhance the adsorption of EDCs to GMs. With the increase of the extent of GM reduction, the adsorption enhancement by the presence of CTAB weakened. This could be attributed to the competition and pore blockage effect caused by the adsorbed CTAB. It is worth noting that the enhancement of CTAB on the adsorption of BPA to GMs was more profound than that of EE2. This is likely because the pore blockage effect plays a less important role in the adsorption of BPA due to its smaller molecular diameter and deformable structure.

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Chen, Zhongyan, Boqun Zhao, Yuhang Qin, Yi Zhou, Yinghua Lu, and Wenyao Shao. "Thin-Film Nanocomposite Reverse Osmosis Membrane with High Flux and Antifouling Performance via Incorporating Maleic Anhydride-Grafted Graphene Oxide." Advances in Polymer Technology 2022 (August 22, 2022): 1–8. http://dx.doi.org/10.1155/2022/4177619.

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Water flux is one of the most important performance parameters of the reverse osmosis (RO) membrane. The higher water flux means lower energy cost when treating the same volume of feed solution with membrane separation technology. However, the increase of membrane water flux always corresponds to the decrease of solvent rejection, known as the “trade-off” effect. In addition, the surface fouling of membranes is often a serious problem, as frequent cleaning not only increases the operating cost but also shortens the life of the membranes. Recently, various hydrophilic nanomaterials have been used to improve the performance of membranes. To fabricate thin film nanocomposite (TFN) RO membrane with high flux and antifouling performance, maleic anhydride-grafted graphene oxide (MG) was successfully synthesized and incorporated into the polyamide (PA) layer via the interfacial polymerization (IP) method. We performed the IP reaction with m-phenylenediamine (MPD) and trimesoyl chloride (TMC) as reactive monomers on a polysulfone (PSF) substrate, and acid absorbent (TEA) and surfactant (SDS) were added to improve the separation performance of the membrane. The effects of MG incorporation on the membrane morphology and separation performance were investigated. SEM and AFM results show that the surface of the MG membrane is rougher than that of the membrane without MG. In addition, excessive loading of MG will lead to aggregation of MG nanosheets. FT-IR spectra indicate that the interaction between MG and PA layers results in an increase of hydrophilic groups on the surface of the TFN membrane, which is further confirmed by the results of the contact angle. The optimal MG doping concentration in the aqueous solution is 0.004 wt%, the water flux of the resultant TFN membrane is significantly increased to 51 L·m-2·h-1, 150% higher than the blank control membrane, which also performs a higher NaCI rejection (97.5% vs. 96.6%). Furthermore, the MG-incorporated RO membrane exhibits superior antifouling performance compared with the blank control membrane.

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Yue, Tongtao, Rujie Lv, Dongfang Xu, Yan Xu, Lu Liu, Yanhui Dai, Jian Zhao, and Baoshan Xing. "Competitive and/or cooperative interactions of graphene-family materials and benzo[a]pyrene with pulmonary surfactant: a computational and experimental study." Particle and Fibre Toxicology 18, no. 1 (December 2021). http://dx.doi.org/10.1186/s12989-021-00436-9.

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Abstract Background Airborne nanoparticles can be inhaled and deposit in human alveoli, where pulmonary surfactant (PS) molecules lining at the alveolar air–water interface act as the first barrier against inhaled nanoparticles entering the body. Although considerable efforts have been devoted to elucidate the mechanisms underlying nanoparticle-PS interactions, our understanding on this important issue is limited due to the high complexity of the atmosphere, in which nanoparticles are believed to experience transformations that remarkably change the nanoparticles’ surface properties and states. By contrast with bare nanoparticles that have been extensively studied, relatively little is known about the interactions between PS and inhaled nanoparticles which already adsorb contaminants. In this combined experimental and computational effort, we investigate the joint interactions between PS and graphene-family materials (GFMs) with coexisting benzo[a]pyrene (BaP). Results Depending on the BaP concentration, molecular agglomeration, and graphene oxidation, different nanocomposite structures are formed via BaPs adsorption on GFMs. Upon deposition of GFMs carrying BaPs at the pulmonary surfactant (PS) layer, competition and cooperation of interactions between different components determines the interfacial processes including BaP solubilization, GFM translocation and PS perturbation. Importantly, BaPs adsorbed on GFMs are solubilized to increase BaP’s bioavailability. By contrast with graphene adhering on the PS layer to release part of adsorbed BaPs, more BaPs are released from graphene oxide, which induces a hydrophilic pore in the PS layer and shows adverse effect on the PS biophysical function. Translocation of graphene across the PS layer is facilitated by BaP adsorption through segregating it from contact with PS, while translocation of graphene oxide is suppressed by BaP adsorption due to the increase of surface hydrophobicity. Graphene extracts PS molecules from the layer, and the resultant PS depletion declines with graphene oxidation and BaP adsorption. Conclusion GFMs showed high adsorption capacity towards BaPs to form nanocomposites. Upon deposition of GFMs carrying BaPs at the alveolar air–water interface covered by a thin PS layer, the interactions of GFM-PS, GFM-BaP and BaP-PS determined the interfacial processes of BaP solubilization, GFM translocation and PS perturbation.

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Song, Yun, Chengjun Rong, Xing Feng, Yujian Liu, and Yan Zhang. "Heterostructured rGO/MoS₂ to improve friction and wear performance of epoxy resins." Polymer Composites, August 25, 2023. http://dx.doi.org/10.1002/pc.27684.

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AbstractIn order to improve friction and wear performance of epoxy resins, the heterostructure of rGO/MoS2 was synthesized by homogeneously growing molybdenum disulfide on the surface of in‐situ reduced graphene oxide (rGO) via the hydrothermal method. The effect of additive type on the microstructure of rGO/MoS2 was discussed. And the obtained rGO/MoS2 exhibits uniform heterostructure with 100–200 nm flower‐like MoS2 nanoparticles scattering evenly on the surface of rGO when using PVP as the surfactant. Owing to robust hybrid structures and synergetic effects of rGO and MoS2, the friction interface temperature of rGO/MoS2/EP has dropped 37.2°C. And the average friction coefficient and specific wear rate of the composites with 0.60 wt% rGO/MoS2 are just 0.55 and 7.6 × 10−6 mm3 N−1 m−1, decreasing by 19.1% and 92.8% than those of epoxy resin.Highlights Flower‐like MoS2 particles scatter evenly on the surface of in‐situ reduced GO. MoS2 and rGO construct robust hybrid structure and form synergetic effects. The transfer film of hybrid rGO/MoS2 reduces interactions between two surfaces. The friction interface temperature of rGO/MoS2/EP drops 37.2°C. The μ and ws of 0.60 wt%rGO/MoS2/EP are reduced by 19.1% and 92.8%.

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Strommer, Bettina, Alexander Battig, Dietmar Schulze, Leonardo Agudo Jácome, Bernhard Schartel, and Martin Böhning. "SHAPE, ORIENTATION, INTERACTION, OR DISPERSION: VALORIZATION OF THE INFLUENCE FACTORS IN NATURAL RUBBER NANOCOMPOSITES." Rubber Chemistry and Technology, January 19, 2023. http://dx.doi.org/10.5254/rct.23.77961.

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ABSTRACT The addition of nanoparticles as reinforcing fillers in elastomers yields nanocomposites with unique property profiles, which opens the door for various new application fields. Major factors influencing the performance of nanocomposites are studied by varying the type and shape of nanoparticles and their dispersion in the natural rubber matrix. The industrial applicability of these nanocomposites is put into focus using two types of graphene and a nanoscale carbon black, all commercially available, and scalable processing techniques in the form of a highly filled masterbatch production via latex premixing by simple stirring or ultrasonically assisted dispersing with surfactant followed by conventional two-roll milling and hot pressing. Different processing and measurement methods reveal the potential for possible improvements: rheology, curing behavior, static and dynamic mechanical properties, swelling, and fire behavior. The aspect ratio of the nanoparticles and their interaction with the surrounding matrix prove to be crucial for the development of superior nanocomposites. An enhanced dispersing method enables the utilization of the improvement potential at low filler loadings (3 parts per hundred of rubber [phr]) and yields multifunctional rubber nanocomposites: two-dimensional layered particles (graphene) result in anisotropic material behavior with strong reinforcement in the in-plane direction (157% increase in the Young's modulus). The peak heat release rate in the cone calorimeter is reduced by 55% by incorporating 3 phr of few-layer graphene via an optimized dispersing process.

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Rezazadeh, Najmeh, Shahnaz Danesh, Mohammad Eftekhari, and Morteza Farahmandzadeh. "Application of graphene oxide and its derivatives on the adsorption of a cationic surfactant (interaction mechanism, kinetic, isotherm curves and thermodynamic studies)." Journal of Molecular Liquids, November 2022, 120720. http://dx.doi.org/10.1016/j.molliq.2022.120720.

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Journal articles on the topic 'Graphene-Surfactant Interactions'

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