Addition Of Reduced Graphene Oxide Research Articles

Enhancing environmental sustainability in concrete buildings with zeolite and reduced graphene oxide additives

Enhancing environmental sustainability in concrete buildings with zeolite and reduced graphene oxide additives

Flooding Control by Electrochemically Reduced Graphene Oxide Additives in Silver Catalyst Layers for CO2 Electrolysis.

Electrolyte flooding in porous catalyst layers on gas diffusion electrodes (GDE) limits the stability and high-current performance of CO2 and CO electrolyzers. Here, we demonstrate the in situ electroreduction of graphene oxide (GO) to reduced graphene oxide (r-GO) within a silver catalyst layer on a carbon GDE. The r-GO introduces hydrophobicity regions in the catalyst layer that help mitigate electrolyte flooding during high current density CO2 electrolysis to CO. The flooding-resistant r-GO/Ag-coated GDE achieves a sustained Faradaic efficiency of CO at 94% for more than 8 h, compared to a rapid drop from 95% to 66% in an Ag-coated GDE without r-GO at 100 mA·cm-2. We found that GO enhances the electrochemically active surface area of the catalyst layer during CO2 electrolysis tests because the incorporation of GO increases the roughness of the catalyst layer. The in situ method of electrochemically reducing GO to r-GO provides a low-cost, practical approach that can be applied during standard spray-deposition procedures to develop flooding-resistant GDEs.

Enhanced Electrochemical Performance of Lithium Iron Phosphate Cathodes Using Plasma-Assisted Reduced Graphene Oxide Additives for Lithium-Ion Batteries

One-dimensional lithium-ion transport channels in lithium iron phosphate (LFP) used as a cathode in lithium-ion batteries (LIBs) result in low electrical conductivity and reduced electrochemical performance. To overcome this limitation, three-dimensional plasma-treated reduced graphene oxide (rGO) was synthesized in this study and used as an additive for LFP in LIB cathodes. Graphene oxide was synthesized using Hummers’ method, followed by mixing with LFP, lyophilization, and plasma treatment to obtain LFP@rGO. The plasma treatment achieved the highest degree of reduction and porosity in rGO, creating ion transfer channels. The structure of LFP@rGO was verified through scanning electron microscopy (SEM) analysis, which demonstrated that incorporating 10.0 wt% of rGO into LFP resulted in successful coverage by the rGO layer, forming LFP@rGO-10. In half-cell tests, LFP@rGO-10 exhibited a specific capacity of 142.7 mAh g−1 at the 1.0 C-rate, which is higher than that of LFP. The full-cell exhibited 86.8% capacity retention after 200 cycles, demonstrating the effectiveness of rGO in enhancing the performance of LFP as an LIB cathode material. The outstanding efficiency and performance of the LFP@rGO-10//graphite cell highlight the promising potential of rGO-modified LFP as a cathode material for high-performance LIBs, providing both increased capacity and stability.

Medium entropy FeCoNi nanoalloy supported on reduced graphene oxide for efficient electrochemical detection of roxarsone in food samples

Herein, a novel FeCoNi(b)-800 ternary metal nanoalloy was uniformly mixed with reduced graphene oxide (RGO) to synthesize the FeCoNi(b)-800@RGO(2:1) composite. The addition of RGO not only stopped the accumulation of FeCoNi(b)-800 alloy, but also heightened the electrocatalytic activity of composite. Particularly, the FeCoNi(b)-800@RGO(2:1) composite displayed the significantly strong electrocatalytic capacity for the reduction of roxarsone (ROX). Furthermore, the FeCoNi(b)-800@RGO(2:1) composite possessed enough porosity and metal catalytic sites, facilitating the transport and electrochemical reduction of the ROX. Thus, the FeCoNi(b)-800@RGO(2:1) composite modified glassy carbon electrode (FeCoNi(b)-800@RGO(2:1)/GCE) showed the superb electrochemical detection effect for ROX with relatively wide working range (0.1–1500 μM) and low detection limit (0.013 μM). Importantly, the FeCoNi(b)-800@RGO(2:1)/GCE sensor could accurately determine the contents of ROX in actual pork, chicken, duck and egg samples, indicating that it had good suitability in food safety monitoring.

Synthesis BaFe12O19/RGO Composite As Microwave Absorber For Ku-Band

In this study, a composite microwave absorber consist of barium hexaferrite (BaFe12O19) and Reduced Graphene Oxide (RGO) for Ku-band (12-18 GHz) was prosperous blend. Barium hexaferrite to arrange using the sonochemical method and at calcination temperature of 1000°C and a holding time of 1 hour. Subsequently, commercial RGO was composited with barium hexaferrite at a weight percentage of 6% RGO. The synthesized composite was characterized using X-Ray Diffraction (XRD) to analyze the formed phases, Raman Spectroscopy to confirm the presence of RGO in the composite, and Vector Network Analyzer (VNA) to evaluate the microwave absorption performance. The XRD test results show that there is no change in the crystal structure of barium hexaferrite due to the addition of RGO. The VNA test results showed that the addition of RGO could enhance the reflection loss value of barium hexaferrite. The BaFe12O19/RGO compound displayed a reflection loss value of -14.43 dB at a frequence of 16.50 GHz.

Efficient solar-driven carbon dioxide capture system for greenhouse using graphene-contained deep eutectic solvents

As photosynthesis progresses, the concentration of CO2 within greenhouses rapidly declines, significantly impairing crop growth. In light of the prevailing limitations associated with complex systems, high energy consumption, and safety concerns related to existing CO2 supplementation methods, a novel “solar-driven CO2 capture system” was proposed for the first time in current work, in which high photothermal conversion materials were incorporated into the deep eutectic solvents (DES). This nanofluid system aims to elevate the system's temperature, facilitating the desorption process and promoting the CO2 absorption–desorption cycle. The graphene nanofluid (GNF) prepared with varying mass fractions of reduced graphene oxide (RGO) can raise CO2 absorption capacity. The results indicate that the CO2 absorption capacity has improved from 0.286 g/g to 0.399 g/g, which can be attributed to abundant adsorption sites provided by the surface of RGO for capturing CO2. Furthermore, the addition of RGO improves the photothermal conversion performance of DES. Maximum photothermal conversion efficiency of 94.3 % and a maximum temperature of 75.9℃ have been achieved for DES-500 (with the addition of 500 ppm RGO in DES) under the irradiation of 1000 W/m2; while pure DES presents 32.7 % and 54.7℃, respectively. Notably, GNF also exhibits excellent recyclability and can effectively regulate CO2 concentration within the greenhouse, ensuring normal growth and development of crops.

Sunlight-driven photocatalytic degradation of Norfloxacin antibiotic in wastewater by ZnSe microsphere functionalized RGO composite

The release of hazardous pollutants into the water, such as dyes, phenolic compounds, pesticides, different heavy metals, and antibiotics is the primary cause of environmental pollution. The solar energy-based photocatalysis technique has the potential to eliminate pollutants from the aquatic environment. ZnSe is a significant and commendable II-VI group photocatalyst having 2.82 eV direct band gap energy. Its performance towards degrading antibiotics in the presence of light was improved by anchoring it on the Reduced graphene oxide (RGO) matrix. Solution-processable RGO-ZnSe composites were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Several spectroscopic studies like Raman spectroscopy, ultraviolet-visible spectroscopy, and photoluminescence spectroscopy were employed to illustrate the optical properties of the composites. The findings demonstrate that the ZnSe microsphere was supported effectively onto the two-dimensional RGO matrix. The performance of as-synthesized RGO-ZnSe composites was assessed based on the photocatalytic degradation of the antibiotic Norfloxacin in the presence of simulated solar light. An optimized RGO-ZnSe composite degrades approximately 83.5% of Norfloxacin in 40 min, while controlled-ZnSe photocatalysis only yields 33% in an identical experimental condition. The optimized RGO-ZnSe achieves the highest degradation reaction rate constant (k) of Norfloxacin (k = 0.057 min−1), and the k value is 4.38 times greater compared to the controlled-ZnSe microsphere. The light-dependent catalytic degradation mechanism was examined by employing scavenger experiments which gave away the responsible reactive radicals. Our results establish that the photo-generated hole has the leading role in the degradation of Norfloxacin in our system. In addition to that, the oxide radical and hydroxyl radical has also an important role in the degradation of Norfloxacin under our experimental condition. The finding suggests that the addition of RGO has enhanced photocatalytic performance and cyclic stability by preventing photo-generated electron-hole pair recombination. The photocatalytic oxidative deactivation mechanism of the Norfloxacin antibiotic was proposed. Our study offers new perceptiveness for the design of efficient solution-processable solar light-responsible photocatalysts for environmental pollution remediation.

Photocatalytic Degradation of Methylene Blue and Anticancer Response of In2O3/RGO Nanocomposites Prepared by a Microwave-Assisted Hydrothermal Synthesis Process.

The incorporation of graphene with metal oxide has been widely explored in various fields, including energy storage devices, optical applications, biomedical applications, and water remediation. This research aimed to assess the impact of reduced graphene oxide (RGO) doping on the photocatalytic and anticancer properties of In2O3 nanoparticles. Pure and In2O3/RGO nanocomposites were effectively synthesized using the single-step microwave hydrothermal process. XRD, TEM, SEM, EDX, XPS, Raman, UV-Vis, and PL spectroscopy were carefully utilized to characterize the prepared samples. XRD data showed that synthesized In2O3 nanoparticles had high crystallinity with a decreased crystal size after RGO doping. TEM and SEM images revealed that the In2O3 NPs were spherical and uniformly embedded onto the surface of RGO sheets. Elemental analysis of In2O3/RGO NC confirmed the presence of In, O, and C without impurities. Raman analysis indicated the successful fabrication of In2O3 onto the RGO surface. Uv-Vis analysis showed that the band gap energy was changed with RGO addition. Raman spectra confirmed that In2O3 nanoparticles were successfully anchored onto the RGO sheet. PL results indicated that the prepared In2O3/RGO NCs can be applied to enhance photocatalytic activity and biomedical applications. In the degradation experiment, In2O3/RGO NCs exhibited superior photocatalytic activity compared to that of pure In2O3. The degradation efficiency of In2O3/RGO NCs for MB dye was up to 90%. Biological data revealed that the cytotoxicity effect of In2O3/RGO NCs was higher than In2O3 NPs in human colorectal (HCT116) and liver (HepG2) cancer cells. Importantly, the In2O3/RGO NCs exhibited better biocompatibility against human normal peripheral blood mononuclear cells (PBMCs). All the results suggest that RGO addition improves the photocatalytic and anticancer activity of In2O3 NPs. This study highlights the potential of In2O3/RGO NCs as an efficient photocatalyst and therapeutic material for water remediation and biomedicine.

Investigation of UV-Vis Photoresponse of WO3/RGO Heterostructure-Based Optical Sensor

Combining tungsten oxide (WO3) with feasible reduced graphene oxide (RGO) yields a novel heterostructure so as to improve optical sensing performances. Here, we develop a high-performance WO3/RGO heterostructure-based optical sensor to work in the ultraviolet-to- visible region of electromagnetic spectrum. The WO3/RGO heterostructures with their varying ratios were synthesized via chemical route and were treated for characterization. The nature, structure, and morphology of the heterostructures were confirmed via XRD pattern and scanning electron microscopy (SEM) images. The absorption spectra investigated in the range of 200–800 nm reveal that their absorption peaks and bandgap mainly lie in the UV–Vis region, which gives the idea that these fabricated heterostructures would be well suited for optical sensors to work in the UV–Vis region. The optical sensor having pure RGO, pure WO3, and WO3/RGO heterostructures as detecting materials was fabricated onto Si/SiO2 substrate and was characterized on illuminating it with UV–Vis light of 390-, 532-, and 635-nm wavelengths, and the current–voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}{)}$ </tex-math></inline-formula> and current–time ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${t}{)}$ </tex-math></inline-formula> characteristics were measured. The addition of RGO to WO3 altered the device’s ability to detect UV and visible light while also increasing the output photocurrent to a much higher value. The obtained responsivity, detectivity, and quantum efficiency were found to be 16.24 mA/W, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${16}.{3} \times {10} ^{{7}}$ </tex-math></inline-formula> Jones, and 5.16%, respectively. At the same time, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${t}$ </tex-math></inline-formula> curves show continuous stable peaks under periodic on/off, indicating that the optical sensor is highly stable and the obtained rise and recovery times were much better demonstrating that the device also has good switching capability.

Microstructure and Mechanical Properties of Magnesium Matrix Composites Reinforced by In Situ Reduced Graphene Oxide.

Due to their excellent mechanical properties and large specific surface area, graphene and its derivatives are widely used in metal matrix composites as reinforcements. In this study, the thermal reduction behavior of large-size graphene oxide are investigated systematically, and reduced graphene oxide (RGO) with few residual oxygen groups and good structural integrity is obtained. ZK61 matrix composites with varying content of in situ RGO are fabricated using the semi-powder metallurgy method. The results reveal that the addition of RGO can cause the refinement of the grains and the second phase, which is attributed to the uniform distribution of the RGO throughout the matrix. The formation of nano-MgO particles is beneficial in increasing the interfacial bonding strength between the RGO and the matrix, resulting in simultaneous increments in yield strength and elongation in the RGO/ZK61 composites. The composite containing 0.6 wt.% RGO shows a superior mechanical property, including microhardness of 79.9 HV, yield strength of 203 MPa and excellent elongation of 17.5%, with increases of 20.9%, 8.6% and 7.4%, respectively, when compared with the ZK61 alloy. Quantitative analysis indicates that the main strengthening mechanisms of RGO-reinforced magnesium matrix composites are load transfer strengthening and grain refinement strengthening.

Effect of reduced graphene oxide addition on cathode functional layer performance in solid oxide fuel cells

Solid oxide fuel cells (SOFCs) operating at high temperatures are highly efficient electrochemical devices since they convert the chemical energy of a fuel directly into heat and electrical energy. The electrochemical performance of an SOFC is significantly influenced by the materials and microstructure of the electrodes since the electrochemical reactions in SOFCs take place at three/triple phase boundaries (TPBs) within the electrodes. In this study, graphene in the form of reduced graphene oxide (rGO) is added to cathode functional layer (CFL) to improve the cell performance by utilizing the high electrical properties of graphene. Various cells are prepared by varying the rGO content in CFL slurry (1–5 wt %), the number of screen printing (1–3) and the cathode sintering temperature (900–1100 °C). The electrochemical behavior of the cells is evaluated by electrochemical performance and impedance tests. It is observed that there is a ∼26% increase in the peak performance of the cell coated with single layer CFL having 1 wt % graphene and 1050 °C sintering temperature, compared to that of the reference cell.

Study on anticorrosion properties of reduced graphene oxide reinforced waterborne epoxy coating

Background: The traditional epoxy zinc-rich coating releases some harmful substances such as VOC during the service process, which pollutes the environment and causes great harm to people. Waterborne epoxy coating is an environmentally friendly, non-polluting potential coating. Objective: In this paper, a new reduced graphene oxide (RGO) reinforced waterborne epoxy coating is developed. Methods: Reduced graphene oxide (RGO) is obtained by modifying graphene oxide (GO). The addition of RGO to waterborne epoxy coatings is designed to improve the corrosion resistance of the coatings. The anticorrosion properties of the coating are investigated by electrochemical methods. Results: After the coating was immersed in 3.5wt% NaCl solution for 15 days, the corrosion current of the coating without RGO is greater than that of the coating containing RGO. Coatings with RGO have higher impedance modulus than coatings without RGO. Coating with 0.3% RGO has better corrosion resistance. After the coating was immersed in the salt solution for 55 days, the impedance modulus of the coating with 0.3% RGO increased by 349.11% compared to the coating without RGO. The coating with 0.3% RGO has the minimum corrosion current density, and the maximum polarization resistance and corrosion voltage. Conclusion: The waterborne epoxy coating with 0.3% RGO has the best anticorrosion.

Influence of reduced graphene oxide addition on kerf width in abrasive water jet machining of nanofiller added epoxy-glass fibre composite.

The present study aims to develop a novel hybrid polymer composite with reduced graphene oxide (rGO) as filler and optimize its Abrasive Water Jet Machining (AWJM) parameters for reduced kerf width. The influence of rGO addition on kerf width is analysed in detail along with Pump pressure (bar), Transverse speed (mm/min) and Standoff distance(mm). The experiments are designed based on Taguchi's orthogonal array techniques in which L27 is adopted for three input parameters at three levels. The influence of each factor is used to identify the significance of selected parameters over kerf width, and it was found that stand of distance has a major effect over kerf width irrespective of rGO %. The addition of rGO filler has a significant effect on kerf width, which decreases with the addition of rGO up to 0.2% and kerf width increases for further addition of rGO.

Effect of reduction time of functionalized graphene oxide on the morphology and properties of epoxy composite foams

In this study, N-aminoethylpiperazine (AEP)-functionalized and reduced graphene oxide (RGO) with different structures and properties was prepared by simply tuning the reduction time and then its effect on the rheological, curing and foaming behavior of epoxy resin was carefully investigated using the environment-friendly carbamate as a chemical foaming agent. As the reduction time of RGO increased, the reduction degree of RGO first increased and then levelled off but the grafted AEP was little affected by the reduction time. The addition of RGO undergoing long reduction time improved the viscoelasticity of epoxy/reduced graphene oxide (EP/RGO) composites but weakened the interfacial compatibility of RGO and EP. With increasing the reduction time of RGO, the cell size of EP/RGO composite foams decreased and the cell density increased. However, as compared with pure EP foam, the composite foams containing RGO with lower reduction degree had a larger cell size and a lower density. These results were attributed to the complicated effect of RGO, which not only acted as the heterogeneous nucleating and foaming agent but also affected the viscoelasticity of composites. In addition, as the reduction time of RGO increased, the initial thermal decomposition temperature, storage modulus at room temperature, electrical conductivity, thermal conductivity, and compressive properties of EP/RGO composite foams increased while the glass transition temperature remained unchanged. These results were related not only to the intrinsic properties and dispersion of RGO, but also to the density and cell morphology of the composite foams.

Preparation and mechanism analysis of non-contact respiratory sensor based on ZnO/RGO composites

A humidity sensor based on zinc oxide (ZnO) and reduced graphene oxide (RGO) composites (ZnO/RGO) for non-contact respiratory detection was fabricated by hydrothermal method, and the sensing mechanism of ZnO/RGO was studied by the first principle based on density functional theory. Experiments show that RGO effectively improves responsivity, linearity and hysteresis of ZnO humidity sensor. Compared with ZnO, the resistance of ZnO/RGO humidity sensor achieves 4.5 orders of magnitude with high response of 48282, maximum hysteresis rate of 3.1%, response/recovery time of 2 s/11 s and the best linearity in a range of 11% − 95% RH. First principle calculation shows that the addition of RGO can reduce chemical adsorption energy and enhance physical adsorption energy of ZnO to water molecules, which explains mechanism for the enhanced performance of ZnO/RGO humidity sensor. Furthermore, ZnO/RGO humidity sensor has been successfully used for non-contact detection of respiration frequency under different breathing states, where a simple circuit is designed to realize the visual detection of humidity signal, which shows that ZnO/RGO materials has a practical value in personal medical services and smart health electronic devices.

Effects of Different Nanocarbon Materials on the Properties of Al/MoO3/NCM Thermite Prepared by Electrostatic Spinning.

In order to improve thermal conductivity, energy performance, and combustion performance of the aluminum-containing thermite, nanocarbon materials were added to thermite. Aluminum/molybdenum and trioxide/nanocarbon materials (Al/MoO3/NCM) were fabricated by electrostatic spinning technology. The Al and MoO3 particles of the nAl/MoO3/NCM thermite are much smaller than nitrocellulose (NC); thus, the two components can be better attached to NC fibers. Results on thermal conductivity demonstrated that the addition of NCM can improve the thermal conductivity of Al/MoO3, and the addition of reduced graphene oxide (RGO) has a more significant impact on thermal conductivity. Energy performance analysis results indicated that the energy performance of Al/MoO3/NCM thermite spinning is the best when the value of combustion oxygen equivalent ratio (Φ) is 0.90–1.00. The combustion performance results show that the addition of NCM can significantly increase the combustion rate of thermites, and the addition of RGO improves its combustion rate the most, followed by carbon nanotubes (CNT) and nanoflake graphite (NFG) being the lowest. By changing the shape of the Al/MoO3/NCM charge and the internal composition of the charge, the sensitivity of the agent can be adjusted, and the matching performance and use performance of the electric igniter can be improved.

Enhanced microwave absorption performance of graphene/doped Li ferrite nanocomposites

In the present study, Microwave absorbing Li-Sr, Li-Co ferrite nanoparticles and RGO/Li-Sr, RGO/Li-Co ferrite nanocomposites containing Li ferrite and reduced graphene oxide (RGO) were synthesized to further improve the microwave absorption performance of Li ferrite nanoparticles (LiFe5O8). The Li-Sr and Li-Co nanoparticles were synthesized by thermal treatment method, the RGO/Li-Sr and RGO/Li-Co nanocomposites were obtained by a polymerization method and were characterized by different techniques. The electromagnetic wave absorption properties of the samples were evaluated by vector network analyzer (VNA) in the frequency range of 2–18 GHz. The magnetic and dielectric loss, impedance matching, and electromagnetic wave absorption of the samples are significantly improved through the addition of RGO. Experimental results revealed that the RGO/Li-Co nanocomposite considerably increased microwave absorption. The minimum reflection loss (RL) of RGO/Li-Co also was found to reach −46.80 dB at the thickness of 3 mm and the effective absorption bandwidth (≤-10 dB) amounted to 6.80 GHz (from 10.52 to 17.32 GHz), which was much higher in comparison with pure Li and Li-Co ferrites nanoparticles. Due to the synergistic effect between magnetic loss and dielectric loss and the good impedance matching, the RGO/Li-Co nanocomposite may be regarded as a new candidate for microwave absorbing materials characterized with a broad effective absorption bandwidth at thin thicknesses.

The effect of reduced graphene oxide addition on methane production from municipal organic solid waste

AbstractBACKGROUNDConductive materials have become the focus of recent studies to accelerate and stabilize the conversion of organic wastes to methane in anaerobic digestion processes. In this study, the effect of the addition of reduced graphene oxide (rGO) on biogas/biomethane production from municipal organic solid wastes in anaerobic batch reactors was investigated. In this context, the effect of loading ratios (0, 0.5, 1 and 2 gVS inoculum (gVS nutrient)−1) and rGO addition at different concentrations (0, 10, 20 and 30 mg L−1) was examined during a 45‐day study period.RESULTSThe highest biogas production reached a level of 816 ± 14 mL (gVS)−1 when substrate/inoculum ratio was 1 and 20 mg L−1 rGO was added (50% more than the group without rGO added). Addition of 30 mg L−1 rGO resulted in 667 ± 12 mL (gVS)−1 corresponding to 23% higher biogas production compared to the control reactor without rGO. The highest cumulative biomethane production was observed to be 525 ± 20 mL (gVS)−1 in the reactor with 20 mg L−1 rGO added in which substrate/inoculum ratio was 1. In the reactors with 10 and 30 mg L−1 and without rGO addition biomethane productions were 448 ± 21, 401 ± 13 and 323 ± 23 mL (gVS)−1, respectively.CONCLUSIONSResults revealed that the addition of rGO increased biomethane production from municipal organic solid wastes. It is concluded that rGO addition has the potential to be applied for real‐scale facilities within the scope of renewable energy production and circular economy. © 2021 Society of Chemical Industry

Stable Perovskite Solar Cells Using Reduced Graphene Oxide Additive

Reduced graphene oxide (RGO) has been commonly used as an additive in the optoelectronic devices account to its unique properties. Here, we added 6% of RGO into mesoporous titanium dioxide (mp-TiO2) to improve the performance of perovskite solar cells (PSCs). The RGO addition resulting in enhanced the crystal structure and optical absorbance of the corresponding perovskite film. The charge transport also was improved and recombination processes reduced due to better interfacial perovskite/mp-TiO2 contact. With this treatment, the optimized PSC achieved a power conversion efficiency of 14%. Most important, the humid long-term stability was improved after using RGO additive. PSCs with RGO maintained about 90% of their original performance after storage in ambient air with a relative humidity of 30-50%.

The impact of reduced graphene oxide on the properties of polyamide 6

Polyamide 6 (PA6) nanocomposites with electric and thermal conductive properties were formulated via melt processing of PA6 and diff erent inclusion of reduced graphene oxide (RGO). These nanocomposites showed that the small percolation threshold and the perfect formation of conductive link form with 0.5 wt % and ~3.0 wt % of RGO, respectively. Examination of crystallization confi rmed that RGO enabled the crystallization of PA6 structure mostly through speeding up the formation ofcrystal nucleus, reaching the biggest and the smallest of crystal grain extent with RGO inclusion up to 2.0 wt % what enabled the generation of the most unfl awed crystalline matrix. Dynamic rheological testing results indicated the frequency-independence of G’ and abruptly decrease phase angle at the small-frequency area via RGO content of 2.0 wt % specifi es the alteration state from liquid-state to solidstate rheological performance, and validates the development of percolation link structure with RGO in the function of a crosslinking factor. The progress of fi re-retardant characteristics of PA6 was att ained due to the inclusion of RGO in the PA6 structure. Morphological research showed that RGO was spread consistently in the PA6 structure. The outcomes of cone calorimetry showed that the fl ame-retardantcharacteristics of PA6 were promoted with the addition of RGO in the PA6 structure. These tests show substantial capacity for the bulk manufacture of electric conductive polymer/RGO nanocomposites.