Incorporation Of rGO Research Articles

Design and Optimization of PEDOT/Graphene Oxide and PEDOT/Reduced Graphene Oxide Electrodes to Improve the Performance of Microbial Fuel Cells, Accompanied by Comprehensive Electrochemical Analysis

A comprehensive investigation into the design and electrochemical optimization of composite electrodes consisting of poly(3,4-ethylenedioxythiophene) (PEDOT)/graphene oxide (GO)/Methanococcus deltae and reduced graphene oxide (rGO)/Methanococcus deltae hybrids, anchored onto stainless-steel (SS) substrates, has been conducted. The GO and rGO materials were synthesized using a modified Hummer method. The resulting SS/PEDOT/GO and SS/PEDOT/rGO composite electrodes were subjected to systematic electrochemical characterization, focusing on the PEDOT p-type and n-type doping/undoping processes within diverse solvent environments (CH3CN and H2O) and electrolyte compositions (LiClO4 and KCl). Raman spectroscopy analysis confirmed the successful integration of graphene derivatives into the electrode structures, while field-emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) revealed increased surface roughness upon GO and rGO incorporation. This increase in surface roughness is believed to enhance the adhesion of Methanococcus deltae microorganisms and facilitate efficient electron transport. Electrochemical measurements showed that the resulting SS/PEDOT/GO and SS/PEDOT/rGO anodes exhibit remarkable electrocatalytic activity. The SS/PEDOT/GO electrode achieved a maximum power density of 1014.420 mW/cm2, while the SS/PEDOT/rGO electrode reached 632.019 mW/cm2.

In-situ grown hexagonal rod-like ZIF-L(Zn/Co) variant on reduced graphene oxide (rGO) for the enhanced electrochemical sensing of acetaminophen

Graphene – one of the most regarded materials in the world of Flatland has a substantial role in sensing applications due to its exceptional properties. Combining graphene with MOF can effectively mitigate the limitations of MOF while synergistically enhancing their unique properties. In this research work, we present a new hybrid composite of Zeolite Imidazolate Framework-L made composite with reduced graphene oxide, ZIF-L(Zn/Co)/rGO (ZLG) and applied its electrocatalytic performance in the sensitive detection of acetaminophen (AP). The mixture was prepared via a simple in-situ solvothermal method whose physico-chemical nature was investigated in detail. The ZIF-L phase identification, morphological change of ZIF, confirmation of rGO incorporation, and chemical composition analysis were established using the XRD, SEM, Raman and XPS respectively. Additionally, the kinetics of electron transfer was studied by EIS. Thereafter, proper optimization of various sensor parameters such as pH, scan rate and analytical performance were executed. Preliminary sensing studies carried out by cyclic voltammetry revealed an enhancement in peak current from 0.48µA to 1.05µA upon incorporation of rGO into the ZIF-L(Zn/Co) hybrid. Compared with reported studies along a similar vein, from the differential voltammetric analysis the ZLG-modified GCE displays a high selectivity towards AP with a broad linear range of 1 µM – 2060 µM exhibiting a sensitivity and LOD of 8.145 µA/mM and 162 nM respectively. The real-time validation of the sensor in paracetamol tablets and biological samples of human blood and urine exhibited recovery values in the range of ∼ 94 % − 102 %. Hence, this suggests a reliable practical applicability of the sensor owing to the high catalytic, large surface area and increased conductivity of the nanocomposite.

Enhanced Mechanical Properties and Degradation Control of Poly(Lactic) Acid/Hydroxyapatite/Reduced Graphene Oxide Composites for Advanced Bone Tissue Engineering Application

This study explores the enhancement of poly(lactic acid) (PLA) matrix using calcium hydroxyapatite (cHAP) and reduced graphene oxide (rGO) for developing composite scaffolds aimed at bone regeneration applications. The PLA composites were fabricated through solvent evaporation and melt extrusion and characterized by various techniques, including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and mechanical testing. The incorporation of cHAP and rGO significantly improved the thermal, mechanical, and morphological properties of the PLA matrix. Mechanical testing revealed that adding 10% cHAP and varying amounts of rGO (0.1%, 0.3%, 0.5%) enhanced tensile and compressive strengths, with the highest improvements observed at 0.5% rGO content. Thermal analysis showed increased thermal stability with higher degradation temperatures for the composites. Spectroscopic analyses confirmed the effective integration of cHAP and rGO into the PLA matrix with characteristic peaks of the fillers identified in the composite spectra. In vitro, degraded action tests in phosphate-buffered saline (PBS) at pH 7.4 over 12 months indicated that composites with higher rGO content exhibited lower mass loss and better mechanical stability. Furthermore, finite element analysis (FEA) simulations were performed to validate the experimental results, demonstrating a strong correlation between simulated and experimental compressive strengths. This novel approach demonstrates the potential of PLA/cHAP/rGO composites in creating effective and biocompatible scaffolds for tissue engineering, providing a comprehensive analysis of the synergistic effects of cHAP and rGO on the PLA matrix and offering a promising material for bone regeneration applications.

Tailoring 3D-printed sensor properties with reduced-graphene oxide: improved conductive filaments.

Thedevelopment of a tailored filament is reportedcomposed of reduced graphene oxide (rGO) and carbon black (CB) in a polylactic acid (PLA) matrix and its use in the production of electrochemical sensors. The electrodes containing rGO showed superior performance when compared with those prepared in the absence of this material. Physicochemical and electrochemical characterizations of the electrodes showed the successful incorporation of both rGO and CB and an improved conductivity in the presence of rGO (lower resistance to charge transfer). As a proof-of-concept, the developed electrodes were applied tothe detection of the forensic analytes TNT and cocaine. The electrodes containing rGO presented a superior analytical performance for both TNT and cocaine detection, showing the lower limit of detection values (0.22 and 2.1µmol L-1, respectively) in comparison withpure CB-PLA electrodes (0.93 and 11.3µmol L-1, respectively). Besides, better-defined redox peaks were observed, especially for TNT, as well as increased sensitivity for both molecules.

High-performance NF-loaded F-NiFe-LDH/rGO nanoflower/nanosheet composite electrode material achieving enhanced specific capacitance and energy density for supercapacitor

High-performance nanostructured F-NiFe-LDH/rGO composite electrode materials with F-NiFe-LDH nanoflowers and rGO nanosheets are synthesized in a controlled hydrothermal method by leveraging the strong synergistic effects between the components, enabling the construction of F-NiFe-LDH/rGO//AC asymmetric supercapacitors. The incorporation of rGO significantly enhances electron transport, resulting in an exceptional specific capacitance of 2860 F g−1 at a current density of 1 A g−1, with a remarkable capacity retention of 102 % after 1000 cycles. This represents a notable improvement in electrochemical energy storage, with surface-controlled capacitance contributing more in alkaline electrolytes for F-NiFe-LDH/rGO composite compared to F-NiFe-LDH alone. The asymmetric supercapacitor device exhibits a specific capacitance of 354 F g−1 at 1 A g−1, maintaining 92.31 % of its initial capacitance after 1000 charge/discharge cycles at 5 A g−1, and achieves an impressive energy density of 110 Wh kg−1 at 1 A g−1. The innovation of this work lies in the controllable preparation of nanostructured F-NiFe-LDH-rGO supercapacitor electrode material with enhanced specific capacitance and energy density by the synergistic effect between F-NiFe-LDH and rGO. This work offers a solid foundation for creating high-performance supercapacitor electrode materials and devices for energy storage applications.

Prussian White/Reduced Graphene Oxide Composite as Cathode Material to Enhance the Electrochemical Performance of Sodium-Ion Battery.

Prussian white (PW) is considered a promising cathode material for sodium-ion batteries. However, challenges, such as lattice defects and poor conductivity limit its application. Herein, the composite materials of manganese-iron based Prussian white and reduced graphene oxide (PW/rGO) were synthesized via a one-step in situ synthesis method with sodium citrate, which was employed both as a chelating agent to control the reaction rate during the coprecipitation process of PW synthesis and as a reducing agent for GO. The low precipitation speed helps minimize lattice defects, while rGO enhances electrical conductivity. Furthermore, the one-step in situ synthesis method is simpler and more efficient than the traditional synthesis method. Compared with pure PW, the PW/rGO composites exhibit significantly improved electrochemical properties. Cycling performance tests indicated that the PW/rGO-10 sample exhibited the highest initial discharge capacity and the best cyclic stability. The PW/rGO-10 has an initial discharge capacity of 128 mAh g-1 at 0.1 C (1 C = 170 mA g-1), and retains 49.53% capacity retention after 100 cycles, while the PW only delivers 112 mAh g-1 with a capacity retention of 17.79% after 100 cycles. Moreover, PW/rGO-10 also shows better rate performance and higher sodium ion diffusion coefficient (DNa+) than the PW sample. Therefore, the incorporation of rGO not only enhances the electrical conductivity but also promotes the rapid diffusion of sodium ions, effectively improving the electrochemical performance of the composite as a cathode material for sodium-ion batteries.

Operando X-ray and Mass Spectroscopy of Reduced Graphene Oxide ( rGO )-Mediated Cobalt Catalysts for Boosting the Hydrogen Evolution Reaction

Inserting underlying reduced graphene oxide (rGO) into Co aims to regulate the chemical integrity and catalytic ability of the Co upper layer for hydrogen evolution reaction (HER) as a green-hydrogen goal. Principally, an mass spectrometer indicates 3.8 times more considerable hydrogen generation in Co/rGO than in Co. The spectroscopical approaches, combining soft and hard X-ray probing, illustrate the chemical oxidation evolution of electronic Co-3 and Co-4 states differently regarding the underlying rGO contribution. A unique examination is regarded as the phase transition from the initial middle to high oxidation and to deoxidation, related to the intermediate Co0 existence and H2 generation. The chemical adsorption of Co–O(H), Co–Hads, and H2 molecules desorption have been assigned their spectral significances. The rGO mediation indicates two significant metal Co and Co–O(H) blocks in the two-dimensional - domain. Density-functional-theory (DFT) calculation provides the regeneration, sustained stability, and decreasing energy barrier of Co–Hads catalysts due to the rGO incorporation, thereby augmenting the HER enhancement through the alternative Volmer-Heyrovsky process. The experiment, including mass spectrometer, soft, and hard X-ray, provides evidence regarding the catalyst’s HER enhancement. This study offers insights into the chemical composition, electronic structure, and active role of Co bonded with or without the extinct OH and H bonds, advancing our comprehension of electrocatalytic reactions, thus taking our knowledge of composite materials to stepwise electrocatalytic reactions forward. This cutting-edge experiment under environment and DFT studies gives critical information regarding the catalytic mechanism and chemical stability of the Co and rGO materials. Published by the American Physical Society 2024

Novel NH4V4O10-Reduced Graphene Oxide Cathodes for Zinc-Ion Batteries: Theoretical Predictions and Experimental Validation

This investigation explores the potential of enhancing aqueous zinc-ion batteries (AZIBs) through the introduction of a novel cathode material, NH4V4O10 (NVO), combined with reduced graphene oxide (rGO). Utilizing Density Functional Theory (DFT), it was hypothesized that the incorporation of rGO would increase the interlayer spacing of NVO and diminish the charge transfer interactions, thus promoting enhanced diffusion of Zn2+ ions. These theoretical predictions were substantiated by experimental data acquired from hydrothermal synthesis, which indicated a marked increase in interlayer spacing. Significantly, the NVO–rGO composite exhibits remarkable cyclic durability, maintaining 95% of its initial specific capacity of 507 mAh g−1 after 600 cycles at a current density of 5 A g−1. The electrochemical performance of NVO–rGO not only surpasses that of pristine NVO but also outperforms the majority of existing vanadium oxide cathode materials reported in the literature. This study underscores the effective integration of theoretical insights and experimental validation, contributing to the advancement of high-performance energy storage technologies.

Waste cotton textile-derived cellulose composite porous film with enhanced piezoelectric performance for energy harvesting and self-powered sensing

Integrating flexible piezoelectric nanogenerators (PENGs) into wearable and portable electronics offers promising prospects for motion monitoring. However, it remains a significant challenge to develop environmentally friendly PENGs using biodegradable and cost-effective natural polymers for mechanical energy harvesting and self-powered sensing. Herein, reduced graphene oxide (rGO) and barium titanate (BTO) were introduced into regenerated cellulose pulp to fabricate a composite porous film-based PENG. The incorporation of rGO not only increased the electrical conductivity of the porous film but also enhanced the dispersibility of BTO. Moreover, the unique pore structure of the composite porous film improved the polarization effect of the air inside the pores, thereby greatly boosting the overall piezoelectric performance. The piezoelectric coefficient of the resulting composite porous film reaches up to 41.5 pC·N−1, which is comparable to or higher than those reported in similar studies. Consequently, the PENG assembled from this cellulose/rGO/BTO composite porous film (CGB-PENG) achieved an output voltage of 47 V, a current of 4.6 μA, and a power density of 30 μW·cm−2, approximately three times the output voltage and ten times the power density of similar studies. This work presents a feasible approach for the fabrication of high-performance cellulose-based PENGs derived from recycled waste cotton textiles.

Hybrid TiO2–RGO nanocomposite as high specific capacitance electrode for supercapacitor

This study describes the fabrication of composite electrodes comprising TiO2 and reduced graphene oxide layers using a moderate-temperature hydrothermal method. The morphology, crystalline structure, chemical composition, and optical features of the prepared composites were analyzed by FE-SEM, x-ray diffraction, FTIR, and UV–visible spectroscopy. The cyclic voltammetry (CV) and Nyquist plots were used to assess the electrochemical and impedance responses of the composite electrodes, respectively. The analysis revealed that the incorporation of RGO reduced the TiO2 bandgap to 3.87 eV 3.02 eV and improved the specific capacitance, enhancing the TiO2-RGO electrode’s supercapacitive performance. CV studies highlight that the TiO2-RGO composite has a high specific capacitance of 152 F g−1 at a substantially faster scan rate of 25 mV s−1 in a 1.0 M-KOH dilute electrolyte. These findings confirmed the applicability of the fabricated electrodes as prospective supercapacitor electrodes.

Accelerated, injectable, self-healing, scarless wound dressings using rGO reinforced dextran/chitosan hydrogels incorporated with PDA-loaded asiaticoside

The process of wound healing is intricate and complex, necessitating the intricate coordination of various cell types and bioactive molecules. Despite significant advances, challenges persist in achieving accelerated healing and minimizing scar formation. Herein, a multifunctional hydrogel engineered via dynamic Schiff base crosslinking between oxidized dextran and quaternized chitosan, reinforced with reduced graphene oxide (rGO) is reported. The resulting OQG hydrogels demonstrated injectability to aid in conforming to irregular wound geometries, rapid self-healing to maintain structural integrity and adhesion for intimate integration with wound beds. Moreover, the developed hydrogels possessed antioxidant and antibacterial activities, mitigating inflammation and preventing infection. The incorporation of conductive rGO further facilitated the transmission of endogenous electrical signals, stimulating cell migration and tissue regeneration. In addition, the polydopamine-encapsulated asiaticoside (AC@PDA) nanoparticles were encapsulated in OQG hydrogels to reduce scar formation during in vivo evaluations. In vitro results confirmed the histocompatibility of the hydrogels to promote cell migration. The recovery of the full-thickness rat wounds revealed that these designed OQG hydrogels with the incorporation of AC@PDA nanoparticles could accelerate wound healing, reduce inflammation, facilitate angiogenesis, and minimize scarring when implemented. This multifunctional hydrogel system offers a promising strategy for enhanced wound management and scarless tissue regeneration, addressing the multifaceted challenges in wound care.

Low-cost Ti-6Al-4V containing low content nano-carbon solid solution for achieving high strength and good ductility

With the rapid advancement of the aerospace industry, in addition to higher requirements for material properties, the cost-effective of its production have also attracted more attention. In this work, titanium matrix composite with high performance and low cost was designed using ball milling, spark plasma sintering and hot rolling process, i.e. hydrogenated dehydrogenated Ti and AlV powders as the precursor of Ti-6Al-4 V matrix, and a low content (0.15 wt%) reduced graphene oxide (rGO) with high-activity was selected to reinforce the matrix alloy. The as-rolled composite shows obvious texture orientation along the rolling direction without pores and microcracks. The incorporation of rGO led to the activation of the as-rolled composites along the {0001}[112¯0] type base slip. The as-rolled composite containing only 0.15 wt% rGO exhibits superior yield strength (1308.1 MPa) and ultimate tensile strength (1444.3 MPa), which are 11% and 9.3% higher than those of the matrix alloy, respectively, and the elongation remains at ∼5.6%. The strengthening mechanisms are mainly attributed to the solid solution strengthening effect of interstitial carbon in the matrix after the incorporation of rGO. This work highlights the development potential of low-cost and high-strength titanium matrix composites

Role of Graphene Oxide and Reduced Graphene Oxide in Electric Double-Layer Capacitors: A Systematic Review

The evolution of electric double-layer capacitors (EDLCs) has significantly benefited from advancements in graphene-based materials, particularly graphene oxide (GO) and reduced graphene oxide (rGO). This systematic review consolidates and analyzes existing research on the roles of GO and rGO in enhancing the performance of EDLCs, focusing on synthesis methods, electrode fabrication, electrolytes, and performance metrics such as capacitance, energy density, and cycling stability. Following the PICOS and PRISMA frameworks, a comprehensive literature search was conducted across Scopus, Web of Science, PubMed, and IEEE Xplore, covering the period from 2010 to 2023. A total of 128 articles were initially identified, with 27 studies meeting the inclusion criteria after rigorous screening and full-text analysis. Key findings reveal that the incorporation of GO and rGO in EDLCs leads to significant improvements in specific capacitance, energy density, and cycling stability. Notable advancements include novel synthesis techniques and composite materials such as nitrogen-doped graphene, graphene/polyaniline hybrids, and various metal oxide–graphene composites, which exhibit superior electrochemical performance. However, challenges such as material scalability, environmental sustainability, and consistency in synthesis methods remain. This review stresses the great potential of GO and rGO in the development of high-performance EDLCs and highlights the need for continued research to address existing challenges and further optimize material properties and fabrication techniques.

Structure engineering of nickel silicate/carbon composite with boosted electrochemical performances for hybrid supercapacitors

In the wake of the carbon–neutral era, the exploration of innovative materials for energy storage and conversion has garnered increasing attention. While nickel silicates have been a focal point in energy storage research, their application in supercapacitors (SCs) has been relatively underreported due to poor conductivity. A newly designed architecture, designated as rGO@NiSiO@NiO/C (abbreviated for reduced graphene oxide (rGO), nickel silicate (NiSiO), nickel oxide/carbon (NiO/C)), has been developed to enhance the electrochemical performance of NiSiO. The incorporation of inner rGO provides structural support for NiSiO, enhancing conductivity, while the outer NiO/C layer not only boosts conductivity but also safeguards NiSiO from structural degradation and electrolyte dissolution. This architecture eliminates multi-phase mixtures, facilitating rapid electron/mass transfer kinetics and accelerating electrochemical reactions, resulting in exceptional electrochemical properties. The rGO@NiSiO@NiO/C architecture achieves a specific capacitance of 324F·g−1 at 0.5 A·g−1, with a superb cycle performance of ∼ 91 % after 10,000 cycles, surpassing state-of-the-art nickel silicates. Furthermore, the hybrid supercapacitor (HSC) device incorporating the rGO@NiSiO@NiO/C electrode attains an areal capacitance of 159 mF·cm−2 at 2.5 mA·cm−2, a retention ratio of ∼ 98 % after 10,000 cycles, and an energy density of 0.68 Wh·m−2 (26.7 Wh·kg−1) at 3.4 W·m−2 (343.8 W·kg−1). This study presents a layer-by-layer approach for constructing transition metal silicates/C architectures to enhance their electrochemical performance.

In‐Situ Growth of MgO@rGO Core‐Shell Structure via CO2 Thermal Reaction for Enhanced Photocatalytic Performance

AbstractDegradation of organic pollutants in wastewater is crucial for global environmental health. Semiconductor‐based photocatalytic technologies have received widespread attention due to their ability to directly utilize solar energy, produce no secondary pollution, and offer long‐lasting functionality. However, current photocatalyst preparation technologies face issues such as complex manufacturing processes, low efficiency, and the need for various additives. Therefore, this work proposes a simple and eco‐friendly method to in‐situ growth of reduced graphene oxide (rGO) onto magnesium oxide (MgO), forming a MgO@rGO core‐shell structured photocatalyst through CO2 thermal reaction process. After systematic study, the incorporation of rGO onto MgO core greatly extends the light absorption range from ultraviolet (UV) to visible wavelength, enabling substantially enhanced light capture and photoexcited carriers. Additionally, the core‐shell heterojunction with a built‐in electric field at the interface between MgO and rGO facilitates distinctly the separation and migration of the photogenerated charges. This structure‐induced synergistic effect boosts the photocatalytic performance of MgO@rGO by a factor of 1.7, 4.1, 41.8, and 6.4, compared with MgO (stripped), MgO (pure), rGO, and commercially used TiO2, respectively. This work provides a simple and effective strategy for designing advanced functional nanocomposites to address environmental problems.

Enhanced Peroxymonosulfate activation via Bi 12 CoO 20 /rGO with Near‐Infrared Photothermal Response for Antibiotics Degradation

Against the backdrop of escalating antibiotic pollution, this study presents a novel approach to remediation using a photothermal heterogeneous Fenton‐like catalyst, Bi12CoO20/rGO, which efficiently activates peroxymonosulfate (PMS) under near‐infrared (NIR) light. This catalyst capitalize on the NIR absorption capabilities of Bi12CoO20 and the electron transfer properties of reduced graphene oxide (rGO). The restored sp2 structure of rGO serves as a conduit for electron transfer, crucial for the redox cycle of Co2+/Co3+ that facilitates PMS activation. Moreover, the incorporation of rGO significantly boosts the NIR absorption capacity of Bi12CoO20, thereby enhancing the photothermal conversion efficiency of the composite and further promoting PMS activation. This synergy enables efficient light‐to‐heat conversion and PMS activation, generating reactive oxygen species (ROS) essential for antibiotic degradation. Using levofloxacin (LVX) as a representative pollutant, the developed system achieves an impressive 99% degradation rate within just 30 min under Bi12CoO20/rGO + PMS + NIR conditions. Moreover, this approach demonstrates robust stability and adaptability across diverse water compositions and pH ranges. Its eco‐friendly nature and renewable characteristics position it as a promising solution for combating antibiotic pollution through photothermal Fenton‐like technology, thereby harnessing solar energy for environmental remediation and fostering sustainable water management practices.

Reduced graphene oxide (rGO) reinforced CoCrFeNiMn high entropy alloy: Microstructure, mechanical properties, and corrosion behavior

The CoCrFeMnNi high entropy alloy (Cantor), and its variant incorporating 0.2 wt% reduced graphene oxide (rGO), denoted as Cantor + rGO, were successfully synthesized using mechanical alloying followed by spark plasma sintering. Comprehensive characterization utilizing FESEM, XRD, and TEM provided detailed insights into the microstructural features of the materials. The addition of rGO reduced crystallite size from 209 nm to 169 nm, promoted a uniform distribution of carbide phases of smaller size, and enhanced microhardness from 421.8 HV to 510 HV for Cantor and Cantor + rGO, respectively. The incorporation of rGO into the Cantor structure led to an increase in compressive yield strength (CYS) from 1100 MPa for Cantor to 1250 MPa for Cantor + rGO sample. A significant decrease in corrosion current density of samples from 6.1 ± 1.5 μA/cm2 for Cantor to 1.4 ± 0.9 μA/cm2 for Cantor + rGO was observed due to the addition of rGO reinforcement. Moreover, the pitting corrosion resistance was increased in rGO-reinforced Cantor, as revealed by cyclic polarization test. This research underscores the potential for utilizing rGO as a reinforcing agent to optimize the mechanical and corrosion resistance characteristics of HEAs, offering promising avenues for advanced materials in diverse applications.

A green approach to synthesis of Ag-doped CeO2 nanorods embedded reduced graphene oxide nanocomposite for excellent photocatalytic and antimicrobial activity

In this paper, the Ag-doped cerium oxide nanorods embedded reduced graphene oxide (Ag@CeO2/rGO) nanocomposite was synthesized via Punica Granatum peel extract for for photocatalytic degradation of methylene blue (MB) and 4-nitrophenol (4-NP). The microstructural results confirmed the successful decoration of Ag-doped CeO2 nanorods on rGO matrix. The photocatalytic properties, including photocatalytic degradation, charge transfer kinetics and photocurrent generation, are systematically investigated using electrochemical impedance spectroscopy (EIS), photocurrent transient response (PCTR) and open circuit voltage decay (OCVD). The results of photocatalytic dye degradation measurements indicated that Ag@CeO2/rGO nanocomposite is more effective than pristine CeO2 to degrade the MB dye, and the degradation rate reached 100 % in 60 min. The decomposition of MB with Ag@CeO2/rGO nanostructure followed first-order reaction kinetics with a reaction rate constant (Ka) of 0.0198 min−1. The EIS and OCVD measurements revealed that the Ag doping and incorporation of rGO could suppress the recombination probability in CeO2 by the separation of photo-generated electron–hole pairs, which leads to the enhanced photocurrent generation and photocatalytic activity. The photocurrent density of Ag@CeO2/rGO, CeO2/rGO and pristine CeO2 are 215, 167.4 and 98.8 mAcm−2, respectively.

Interface engineering of composite systems: Focusing on the compatibility of reduced graphene oxide and Bi0.8La0.1Ba0.1Fe0.9Ti0.1O3 hybrid systems

The composite of reduced graphene oxide and perovskite-based ferroelectric materials offers exciting opportunities to enhance the optical performance of optoelectronic devices. The present work reporting rGO modified x(Bi0.8La0.1Ba0.1Fe0.9Ti0.1O3)-1-x(rGO) (La-BBFT/rGO) composite to investigate their structural, morphological, electrical, magnetic and optical properties by using robust solid-state and spun calcination method. X-Ray diffraction patterns confirm the rhombohedral crystal structure with space group (R3c) of both samples with the presence of rGO as second phase. The functional groups present in reduced graphene oxide (rGO) can act as nucleation sites for crystallization, leading to the formation of more grains and Grain boundaries. The ferroelectric phase transition was observed in La-BBFT/rGO composites at comparatively low temperature near 250 °C. The impedance spectroscopy confirms the non-Debye behaviour of relaxation process. The electric and magnetic remanence shows the compatibility of the switching state. Additionally, the optical band gap energy of both samples was evaluated and found to be in the range of 2.0 to 1.9eV. Incorporation of rGO in La-BBFT/rGO, were marginally improved, the dialectic, impedance, and optical properties, which could be beneficial for electronic and optical components in the opto-electronic industries.

Enhanced catalytic degradation of amoxicillin by phyto-mediated synthesised ZnO NPs and ZnO-rGO hybrid nanocomposite: Assessment of antioxidant activity, adsorption, and thermodynamic analysis

Abstract Antibiotics are resistant compounds that become emerging contaminants that cause hazards to human health and the ecological environment due to their wide production and consumption. The present research reveals the remediation of amoxicillin (AMX) antibiotic by catalytic degradation using fabricated zinc oxide (ZnO) and zinc oxide-reduced graphene oxide (ZnO-rGO) catalysts. The characterization of the catalyst was carried out via UV–Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and scanning electron microscopy to evaluate the morphology and composition of synthesised catalyst. The catalytic ability of ZnO-rGO and ZnO was investigated by analysing the degradation of AMX. The ZnO-rGO nanocomposites (NCs) showed improved catalytic performance towards AMX degradation (96%) than pure ZnO nanoparticles (85%), which may be attributed to the incorporation of rGO, which enhanced the adsorption rate and changed the electron–hole recombination rate. The antioxidant potential of synthesised nanomaterials was also analysed by three different methods. The adsorption behaviour was explained through the Langmuir and Freundlich models, and the results revealed that AMX adsorption followed the Freundlich model more closely for both catalysts. The adsorption of AMX was also studied thermodynamically at different temperatures. The negative Gibbs energy change, positive enthalpy change, and entropy change showed the reaction’s spontaneity and endothermic nature. Finally, it can be assumed that the ZnO-rGO NCs could be an effective semiconductor for the degradation of AMX from wastewater.