Nanohybrid Films Research Articles

Enhanced thermal stability photophysical properties of photoselective PMMA/ITO nanohybrid films for greenhouse cooling in hot climates

The current research proposed innovative photoselective greenhouse cooling films made from PMMA/ITO nanohybrids, incorporating varying concentrations of Indium tin oxide nanocrystals (ITO NCs) and the fluorescent organic dye Lumogen F Red300, utilizing the solvent casting method. The morphology and structure were examined using transmission electron microscopy (TEM) and X-ray diffraction (XRD), demonstrating good homogeneity and amorphous nature. The impact of different ITO NC concentrations on physical properties was examined through differential scanning calorimetry (DSC), optical absorption, transmission, reflection, fluorescence, and Fourier transform infrared (FT-IR) spectroscopy. Integrating ITO NCs into the PMMA matrix showed enhanced thermal insulation capabilities of PMMA films while maintaining their transparency to photosynthetically active radiation (PAR). Maintaining this balance is crucial because it enables the films to selectively filter and reflect infrared radiation leading to lower greenhouse temperatures while still allowing the essential light needed for plant growth to pass through. This research is particularly significant for Sustainable Development Goals (SDGs) 2 and 13, especially in hot, water-scarce regions, as it protects plants from thermal stress, promotes growth, and supports food security in developing countries.

New PMMA-InP/ZnS nanohybrid coatings for improving the performance of c-Si photovoltaic cells

Abstract Luminescent down-shifting (LDS) nanohybrid films are considered a potential solution to match the absorption spectrum of photovoltaic (PV) cells with the AM1.5 solar spectrum. LDS films were prepared by spin-coating polymethyl methacrylate (PMMA) doped with indium phosphide/zinc sulfide (InP/ZnS) quantum dots (QDs). The effect of doping concentration was investigated using X-ray diffraction, thermogravimetric analysis, transmission, and fluorescence spectroscopy. The results demonstrated that all PMMA LDS nanohybrid films were amorphous and exhibited thermal and chemical stability for all the doping concentrations of QDs. The optimal doping concentration was 0.06 wt%, demonstrating a tunable emission of the highest fluorescence quantum yield of 92% and the lowest reabsorption effect. This film showed the maximum enhancement of the efficiency of c-Si PV cells by 24.28% due to the down-conversion of ultraviolet A (UVA) portion of solar spectrum (320–400 nm) to match the sensitivity of c-Si PV cells. The implications of these results are significant for advancing affordable and clean energy in alignment with important sustainable development goals.

Semi‐transparent metal electrode‐free all‐inorganic perovskite solar cells using floating‐catalyst‐synthesized carbon nanotubes

AbstractPerovskite solar cells offer a promising future for next‐generation photovoltaics owing to numerous advantages such as high efficiency and ease of processing. However, two significant challenges, air stability, and manufacturing costs, hamper their commercialization. This study proposes a solution to these issues by introducing a floating catalyst‐based carbon nanotube (CNT) electrode into all‐inorganic perovskite solar cells for the first time. The use of CNT eliminates the need for metal electrodes, which are primarily responsible for high fabrication costs and device instability. The nanohybrid film formed by combining hydrophobic CNT with polymeric hole‐transporting materials acted as an efficient charge collector and provided moisture protection. Remarkably, the metal‐electrode‐free CNT‐based all‐inorganic perovskite solar cells demonstrated outstanding stability, maintaining their efficiency for over 4000 h without encapsulation in air. These cells achieved a retention efficiency of 13.8%, which is notable for all‐inorganic perovskites, and they also exhibit high transparency in both the visible and infrared regions. The obtained efficiency was the highest for semi‐transparent all‐inorganic perovskite solar cells. Building on this, a four‐terminal tandem device using a low‐band perovskite solar cell achieved a power conversion efficiency of 21.1%. These CNT electrodes set new benchmarks for the potential of perovskite solar cells with groundbreaking device stability and tandem applicability, demonstrating a step toward industrial applications.image

Deposition of Polypyrrole-Carboxylated Multi-Walled Carbon Nanotube Nanohybrid Thin Film for Surface Plasmon Resonance Sensor

Immobilization of the enzyme is the main problem and critical factor in producing high selectivity and sensitivity of a surface plasmon sensor (SPR). This study is aimed at fabricating a uniform polypyrrole (PPy) - Carboxylated Multi-Walled Carbon Nanotube (MWCNT-COOH) nanohybrid film as a mediator, thereby enhancing the functional groups to attach and immobilize the enzymes for the SPR sensor. This nanohybrid thin film of PPy- MWCNT-COOH was electrodeposited on the surface of gold (Au)/chromium (Cr) by chronoamperometry using potentiostat at 0.7V for 5s and 10s. For the first time, the MWCNT-COOH is utilized and combined with conductive polymer PPy to investigate the SPR sensor at two different wavelengths which are 670 nm and 785 nm. The SPR curves and resonance angle are red-shifted and shallower when the time of electropolymerization increases. However, the resonance angle for the 785 nm optical wavelength is blue-shifted and the full-width-at-half-maximum (FWHM) is smaller compared to the 670 nm optical wavelength. The Fourier-transform infrared spectroscopy (FTIR) spectrum examination reveals the presence of the required functional groups from the fabricated PPy-MWCNT- COOH nanohybrid thin film to attach the enzyme immobilization in future work. In conclusion, the findings of this research can broaden exciting possibilities for the low-cost fabrication of promising SPR sensors at longer wavelengths.

Effect of 105 MeV gold ion irradiation on dielectric properties of PVC/PVDF@BaZrO3 nanohybrid thin film

The PVC/PVDF@BaZrO3 nanohybrid thin films were prepared by solution grown method. The dielectric constant of the films was higher due to BaZrO3 incorporation in the PVC/PVDF matrix. The PVDF and PVC/PVDF nanohybrid films were irradiated with 105 MeV Au2+ ion beam under vacuum condition at room temperature with two ion fluence. The irradiated thin film of PVC/PVDF@BaZrO3 exhibits relatively low dielectric constant with low loss at different temperature because of thermodynamic stability of β-phase. However, almost complete amorphization was observed in BaZrO3 filler in PVC/PVDF@BaZrO3 nanohybrid samples. After being irradiated with a 105 MeV Au2+ ion beam, the (ϵ′) dielectric constant, FTIR and SEM parameters were used to evaluate changes in dielectric and structural properties for all the samples. In FTIR spectra, new peaks appeared at 1705 cm−1, disappeared or minutely shifted due to high energy of ion beam. It is interesting to note that BaZrO3 phase becomes amorphized through 105 MeV Au2+ ion irradiation that causes an increased dielectric constant along with cross-linking effect of nanohybrid films.

Polyimide/titanium dioxide self-cleaning nano-hybrid films with high photocatalytic properties

Self-cleaning films are considered an emerging paradigm of environmentally functional materials. Enhancing the photocatalytic activities of self-cleaning film is a viable strategy for improving its antifouling characteristics. In this work, a polyimide/titanium dioxide (TiO2) film (PI/TiO2) film was developed by casting a mixture of polyamic acid solution and TiO2 hydrosol with a subsequent thermal imidization. TiO2 with a concentration of 1, 3, and 5 ​wt% was successfully incorporated into the PI matrix and was equally distributed in nanometer size in the PI/TiO2 nano-hybrid films. The addition of TiO2 into the film significantly improved its catalytic performance as indicated by the photocatalytic degradation of methylene blue and resazurin solution, suggesting a good self-cleaning property for antifouling applications. In addition, the thermal and mechanical stability of the PI film were improved with the addition of TiO2. After eight cycles, the PI-TiO2 films also demonstrated excellent cycling stability. This study introduces a novel self-cleaning film family composed of PI/TiO2 nano-hybrid film and emphasizes the engineering potential of photocatalytic materials in the context of self-cleaning film.

Photocatalytic thin films based on Au nanoparticles covered by iron oxyhydroxides by hydrothermal process

The use of ultrathin nanohybrid films in photocatalytic applications to decompose pollutants is a desirable and effective approach for industrial and practical purposes. In this study, ultrathin films composed of Fe2O3 oxyhydroxides with Au nanoparticles (NPs; Au–FeOOH) were prepared by Au evaporation deposition, a hydrothermal process, and thermal annealing. Transmission electron microscopy, elemental mapping, and X-ray photoelectron spectroscopy studies confirmed the attachment of the FeOOH matrix to the Au nanoparticles. Au–FeOOH thin films exhibited outstanding photodecomposition ability toward rhodamine 6G in a 0.5 µM aqueous solution under artificial light illumination (120 min; 1000 W m−2); such performance is the best reported thus far for Fe2O3 thin films. The superior photocatalytic activity of the Au–FeOOH nanohybrid thin films is attributed to their broad absorption encompassing the deep ultraviolet-to-near infrared regions and efficient charge transfer between the Au NPs and FeOOH NPs.

Graphene Oxide: Key to Efficient Charge Extraction and Suppression of Polaronic Transport in Hybrids with Poly (3-hexylthiophene) Nanoparticles.

Nanoparticles (NPs) of conjugated polymers in intimate contact with sheets of graphene oxide (GO) constitute a promising class of water-dispersible nanohybrid materials of increased interest for the design of sustainable and improved optoelectronic thin-film devices, revealing properties exclusively pre-established upon their liquid-phase synthesis. In this context, we report for the first time the preparation of a P3HTNPs-GO nanohybrid employing a miniemulsion synthesis approach, whereby GO sheets dispersed in the aqueous phase serve as a surfactant. We show that this process uniquely favors a quinoid-like conformation of the P3HT chains of the resulting NPs well located onto individual GO sheets. The accompanied change in the electronic behavior of these P3HTNPs, consistently confirmed by the photoluminescence and Raman response of the hybrid in the liquid and solid states, respectively, as well as by the properties of the surface potential of isolated individual P3HTNPs-GO nano-objects, facilitates unprecedented charge transfer interactions between the two constituents. While the electrochemical performance of nanohybrid films is featured by fast charge transfer processes, compared to those taking place in pure P3HTNPs films, the loss of electrochromic effects in P3HTNPs-GO films additionally indicates the unusual suppression of polaronic charge transport processes typically encountered in P3HT. Thus, the established interface interactions in the P3HTNPs-GO hybrid enable a direct and highly efficient charge extraction channel via GO sheets. These findings are of relevance for the sustainable design of novel high-performance optoelectronic device structures based on water-dispersible conjugated polymer nanoparticles.

Bio-Electroanalysis Performance of Heme Redox-Center for π-π Interaction Bonding of a Methylene Blue-Graphene Modified Electrode.

Hemeprotein detection has motivated extensive research on the direct reaction of a heme molecule and a redox dye. The present study used methylene blue as both donor and acceptor for a redox reaction. First, the solid phases of methylene blue (MB) and graphene (GP) formed a π-π interaction bond at the aromatic rings. The conductivity of GP was better than that of carbon in a carbon electrode (CE). Then, the working CE was modified using strong adsorption of MB/GP on the electrode surface. The surface of the electrode was investigated using a modified and an unmodified electrode. The electrode's properties were studied using voltammograms of redox couple K3[Fe(CN)6]3-/4-. Its reaction was used to find the active area of the modified electrode, which was 1.76 times bigger than that of the unmodified electrode. The surface coverage values of the modified and unmodified electrodes were 8.17 × 10-6 and 1.53 × 10-5 mol/cm2, respectively. This research also studied the application of hemeprotein detection. Hemoglobin (Hb), myoglobin (Mb), and cytochrome c (Cyt. C) were studied by the reaction of Fe (III/II) at the heme-redox center. The electrocatalytic reaction between MB/GP and hemeproteins produced an anodic peak at 0.35 V for Hb, Mb, and Cyt. C. This nanohybrid film enhanced electron transfer between protein molecules and the modified carbon electrode. The amperometric measurements show that the limit of detection was 0.2 µM, 0.3 µM, and 0.1 µM for Hb, Mb, and Cyt. C, respectively. The measurement spanned a linear range of 0.2 µM to 5 µM, 0.3 µM to 5 µM, and 0.1 µM to 0.7 µM for Hb, Mb, and Cyt. C, respectively. Hb showed the lowest sensitivity compared with Mb and Cyt. C due to the role of steric hindrance in the hemeprotein specificity structure. This study offers a simple and efficient fabrication platform for electrochemical sensors for hemeproteins. When compared to other complex immobilization processes, the fabrication method for this sensor has many benefits, including no need for special chemicals and easy preparation and electrode modification-both of which are crucial for the development of electrochemical sensing devices.

Thermo-Viscoelastic residual stress behavior of fluorinated polyimide based on fluid Instability-Driven shear exfoliated graphenic nanosheet

Attempts to reduce the size of electronic devices result in residual stresses in the polymeric optoelectronic materials used therein, leading to detrimental effects such as microscopic defect formation and macroscopic dimensional changes. In this study, fluorinated polyimide (FPI) reinforced with reduced graphene oxide (RGO) was fabricated by exploiting the instability of the Taylor − Couette flow. This method affords exceptional ultralow residual stresses. High fluid-wall shear stress in Taylor vortex flow (TVF) with axisymmetric instability accelerates the reduction of graphene oxide (GO) even at a low temperature of 85 °C. Using ascorbic acid as a green reducing agent, a highly exfoliated RGO@TVF nanohybrid was obtained, which activated the interaction at the polymer-filler interface. During high-temperature cycling, real-time residual stress–temperature profiles generated at the interface between the FPI/RGO@TVF nanohybrid films and Si wafer substrate were analyzed. The results demonstrated that the residual stress strongly depends on the processing temperature and microstructure and that the stress eventually converges to a zero-stress value (<7 MPa) even at a low RGO@TVF loading of 3 wt%. In addition, the incorporation of RGO@TVF into the FPI resulted in nanohybrid films with a high storage modulus (2126 MPa) and glass transition temperature (330 °C). The results show that the highly exfoliated RGO@TVF provides more contact points between the polyimide chains and RGO@TVF sheets, which increases the polymer-filler compatibility, thereby improving the thermal and dimensional stability.

Exploration of molecularly imprinted polymer (MIP) nanohybrid films as DNA sensors for the detection of porcine

Exploration of molecularly imprinted polymer (MIP) nanohybrid films as DNA sensors for the detection of porcine

Structural and Optical Properties of Graphene-ZnO Nanohybrid Thin Films Synthesized by Spray Pyrolysis

Graphene-ZnO nanohybrid thin films were prepared by spray pyrolysis technique at 350 °C. Different graphene nanoplate concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 wt.% were used to deposit films on quartz substrates. The Structural and optical properties of the nanohybrid films have been investigated. X-ray diffraction XRD results show that the films have a hexagonal wurtzite polycrystalline structure and no secondary phases were observed. The structural parameters of crystallite size, dislocation density, and microstrain have indicated that the addition of graphene has a strong effect on the microstructure of zinc oxide films. Surface morphological analysis of the ZnO-graphene films reveals that the graphene content effectively modifies the morphologies and grain growth of the ZnO microstructure. It was also found from the optical properties that the maximum energy gap for pure ZnO films was 3.4 eV which decreases to 2.7 eV as the concentration of graphene increases to 0.5 wt.%. Results confirmed that graphene can be used as an efficient modifier for band gap engineering and the microstructure of ZnO thin films for enhanced photovoltaic applications.

A Polypyrrole/Nanoclay Hybrid Film for Ultra-Sensitive Cardiac Troponin T Electrochemical Immunosensor.

An electrochemical immunosensor based on a nanohybrid film of carboxylated polypyrrole and amine nanoclay was developed for label-free detection of the human cardiac troponin T (cTnT). The nanohybrid film was formed in situ on the surface of the glassy carbon electrode, followed by the covalent immobilization of anti-troponin T antibodies by glutaraldehyde. Morphological and chemical characterizations of the nanohybrid film were performed by scanning electron microscopy and Fourier-transform infrared spectroscopy. Under the optimized conditions, a calibration curve for cTnT in spiked serum was obtained by square wave voltammetry, and a low limit of detection and quantification was achieved (0.35 and 1.05 pg mL−1, respectively). This was the first time that this type of nanohybrid film was used in the development of an immunosensor for cTnT that proved to be a simple and efficient strategy for the manufacture of a label-free electrochemical device that could be applied in the diagnosis of acute myocardial infarction.

Green Synthesis of ZnO/BC Nanohybrid for Fast and Sensitive Detection of Bisphenol A in Water

A nanohybrid of zinc oxide and biochar (ZnO/BC) with high conductivity was green synthesized using a simple hydrothermal method, and utilized for the sensitive detection of bisphenol A (BPA) by coating the nanohybrid film on an electrode of glassy carbon. The ZnO/BC presented greatly improved electrocatalytic performance and electron transfer ability compared to the zinc oxide and biochar. The ZnO/BC film-coated electrode could detect the BPA in aqueous solution within 3 min while neglected interference from higher concentrations of regularly existing ions and similar concentrations of estradiol (E2), phenol, dichlorophenol (DCP), and ethinylestradiol (EE2). Under optimal conditions, the linear range of BPA detection was 5 × 10−7~1 × 10−4 mol/L, with a detection limit of 1 × 10−7 mol/L, and the detection sensitivity was 92 mA/M. In addition, the ZnO/BC electrode could detect BPA in a real water sample with good signal recovery. This electrode, with the advantages of an easy preparation, low cost, and fast response time, could be potentially applicable for environmental monitoring.

A three dimensional porous diamond-multilayer graphene nanohybrid film for surface-enhanced Raman spectroscopy

Development of excellent surface-enhanced Raman scattering (SERS) substrate with high sensitivity, low limit of detection (LOD), good uniformity and high stability are still challenging in practical application. Herein, we prepared a diamond-multilayer graphene nanohybrid (DMGN) film with unique three-dimensional (3D) porous wall-like morphology as a new SERS substrate, through a microwave plasma chemical vapor deposition (MPCVD) method. A simple wet-chemical oxidation treatment performed on DMGN substrate resulted in an obvious improvement in LOD value, from 10−9 mol/L to 10−11 mol/L, and enhancement factor (EF), from 4.2 × 104 to 3.9 × 106, for the detection of Rhodamine B (RhB), simultaneously along with good homogeneity and long-term stability. More importantly, the oxidized DMGN (ODMGN) substrate also exhibited good SERS performance for the detection of a real explosive (FOX-7), including low LOD of 10−6 mol/L and large EF of 527. Finally, first-principles density functional theory (DFT) simulation revealed that SERS enhancement of ODMGN substrate was mainly attributed to the transfer electron between HN- functional group of FOX-7 and the -OH and O functional groups of ODMGN substrate. These unique 3D porous nanohybrid films showed momentous potential to realize a SERS substrate with excellent performance.

Enhanced Efficiency of Dye-Sensitized Solar Cells Based on Polymer-Assisted Dispersion of Platinum Nanoparticles/Carbon Nanotubes Nanohybrid Films as FTO-Free Counter Electrodes.

In this study, polymer-assisted dispersants are used to stabilize the nanohybrids of platinum nanoparticles (PtNPs)/carbon nanotubes (CNTs) through non-covalent bond forces. These dispersants aim to replace the florine-doped tin oxide (FTO) glass in traditional dye-sensitized solar cells (DSSCs) as counter electrodes. The large specific surface area, high conductivity, and redox potential of PtNPs/CNT nanohybrids are used as the basis to utilize them as the counter electrode material to fabricate a dye-sensitized solar cell. The conductivity results indicate that the resistance of the PtNP/CNT nanohybrid film can be reduced to 7.25 Ω/sq. When carbon nanotubes are mixed with platinum nanoparticles at a weight ratio of 5/1, the photoelectric conversion efficiency of DSSCs can reach 6.28%. When using the FTO-containing substrate as the counter electrode, its conversion efficiency indicates that the micro-/nano-hybrid material formed by PtNPs/CNTs also exhibits an excellent photoelectric conversion efficiency (8.45%) on the traditional FTO substrate. Further, a large-area dye-sensitive cell is fabricated, showing that an 8 cm × 8 cm cell has a conversion efficiency of 7.95%. Therefore, the traditional Pt counter electrode can be replaced with a PtNP/CNT nanohybrid film, which both provides dye-sensitive cells with a high photoelectric conversion efficiency and reduces costs.

Enzyme-based sensing on nanohybrid film coated over FTO electrode for highly sensitive detection of antibiotics.

Cefepime and Meropenem are the new class of antibiotics, which are particularly used as last potent defender or the antibiotics of the last resort against multi-resistant bacterial species. In this paper, an impedance-based electrochemical biosensor was fabricated for identifying antibiotics of last resort in the forensic samples including gastric lavage and other body fluids. The sensor was developed using platinum nanoparticles (PtNPs) and electrodeposited zinc oxide- zinc hexacyanoferrate hybrid film (ZnO/ZnHCF) on the surface of a fluorine-doped glass electrode (FTO). Further, penicillinase was immobilized onto the modified electrode using penicillinase enzyme. The developed biosensor exhibits agood analytical response for the detection of antibiotics evaluated using electrochemistry studies. The linear response of thefabricated electrode was observed from 0.1 to 750µM and the electrode limit of detection (LOD) was observed as 0.1µM. The sensor confirms good accuracy, ishighly selective, and sensitive for the target. While storingthe modified electrode at 4°C, the stability of biosensor was evaluated for 45days, and activityloss of 30-40% was observed. Thehighly sensitive interface of Penicillinase@CHIT/PtNP-ZnO/ZnHCF/FTO electrode shows a promising future in forensic studies.

Influence of Fluorine-Containing Monomer Content on the Hydrophobic and Transparent Properties of Nanohybrid Silica Polyacrylate Coating Materials.

Nanosilica-modified, fluorine-containing polyacrylate hybrid coating materials, consisting of dodecafluoroheptyl methacrylate (DFMA), methyl methacrylate (MMA), 2-ethyl hexyl acrylate (2-EHA), 3-(trimethoxysilyl) propyl methacrylate (KH-570), and tetraethylorthosilicate (TEOS), are synthesized successfully by free radical polymerization and the sol–gel process. It is revealed that the content of the fluorine-containing polyacrylate hybrid coating materials from DFMA monomers significantly improves the properties of the films. The polyacrylate coating film prepared with a weight ratio of DFMA/MMA at 1:5 exhibits the largest water contact angle of 105.4°, which demonstrates that DFMA can effectively improve the hydrophobicity of the coating film. Moreover, the silicon coupling agent (KH-570) is used to graft silica with acrylate. Spherical in shape, the surface morphology of the nanohybrid film exhibits a core–shell structure, which increases the surface roughness and enhances the hydrophobic properties. The as-prepared fluorine-containing nanohybrid silica polyacrylate film possesses a high transmittance of 89–97% in the visible light region, indicating its potential as a very attractive solution in many practical areas.

Design of a ductile carbon nanofiber/ZrB2 nanohybrid film with entanglement structure fabricated by electrostatic spinning

Polyacrylonitrile (PAN), a kind of multi-purpose man-made polymer material, has been widely used in various products, including carbon fiber precursor fiber manufacturing. Organic/inorganic nanocomposites can provide precursor material with unique properties due to optimal structural design. Herein, PAN based carbon nanofiber (CNF) coated zirconium borate (ZrB2) particles fiber film was prepared via electrostatic spinning strategy. Crosslinking network between carbon atoms formed at 280 °C due to long chain PAN molecules, which underwent pyrolysis at 800–1200 °C. Scanning electron microscope analysis showed that ductile CNF/ZrB2 hybrid material with entanglement structure was successfully fabricated. Phase composition of the materials was analyzed by X-ray diffractometer, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy, which confirmed the presence of carbon atoms in the materials. Entanglement structure between CNFs and ZrB2 enhanced tensile performance of nanohybrid film, in which CNF film with 25% ZrB2 content exhibited optimal mechanical properties. The design of nanohybrid structure provides facile and universal approach for exploration of organic/inorganic nanocomposites with controlled structures and excellent mechanical properties.

Pt-free and efficient counter electrode with nanostructured CoNi2S4/rGO for dye-sensitized solar cells

Solar cells of the third generation aim to reduce costs and/or boost the efficiency of current solar cells. The goal of this paper is to systematically research a cobalt nickel sulfide/reduced graphene oxide (CoNi2S4/rGO) nanocomposite sandwich type dye sensitized solar cell (DSSC) prototype as a counter electrode synthesized by a simple one-step hydrothermal process. The structural and morphological characterization of the nanocomposite reveals that cubic structure with spherical shaped nanoparticles (25–30 nm), which is uniformly decorated on the rGO sheets. When used as a counter electrode, the optimized CoNi2S4/rGO nanohybrid film delivers a high photo-conversion efficiency of 10.21%, which is higher than that theDSSCmanufacturedascounterelectrodewithPt (6.45%) and even better than that with pristine CoNi2S4 (3.45%). Cyclic voltammetry, Tafel plot and electrochemical impedance spectroscopy show that the as-synthesized CoNi2S4/rGO nanohybrid counter electrode exhibits an excellent electrocatalytic property than compared with pure CoNi2S4 counter electrode (CE). This research also offers some clues to the potential growth and rational design of CoNi2S4/rGO nanohybrid counter electrode for advance energy applications.