Efficient Electrocatalyst For Oxygen Evolution Reaction Research Articles

MOF-derived S-doped NiCo2O4 hollow cubic nanocage for highly efficient electrocatalytic oxygen evolution

Inducing the surface reconstruction of spinels is critical for improving the electrocatalytic oxygen evolution reaction (OER) activity. Herein, S-doped NiCo2O4 hollow cubic nanocage was synthesized by anion etching Metal-Organic Frameworks (MOFs) template and air annealing strategies. The hollow structure possesses a large specific surface area and pore size, facilitating active site exposure and mass transport. S2− doping regulates the electronic structure, reducing the oxidation potential of Ni sites during the OER process, thus promoting the surface reconstruction into γ-NiOOH active species. Meanwhile, S2− doping enhances conductivity, accelerating interfacial charge transfer. As a result, S-NiCo2O4-6 exhibits superior OER activity (262 mV overpotential @ 10 mA cm−2) and stability in 1.0 M KOH solution. Furthermore, 20 % Pt/C‖S-NiCo2O4-6 only needs 1.832 V to achieve 50 mA (the electrochemical active area is 4 cm2) in a homemade anion exchange membrane (AEM) electrolyzer. This work proposes a novel approach for preparing efficient anion-doped spinel-based OER electrocatalysts.

Ligand-mediated electrocatalytic activity of Cu-imidazolate coordination polymers for OER in water electrolysis

Copper is an Earth-abundant element promising for the synthesis of robust and efficient oxygen evolution reaction (OER) electrocatalysts. In this study, three Cu-imidazolate coordination polymers (Cu-Im, Cu-mIm, and Cu-bIm) are electrochemically synthesized and examined as OER catalysts whose activity can be modulated by the coordinating ligands of imidazole (Im), 2-methylimidazole (mIm), and benzimidazole (bIm). During the water electrolysis, Cu-Im and Cu-mIm are partially oxidized to form CuO particles, a well-known OER catalyst, while Cu-bIm does not. Due to the in situ formation of CuO during the electrolysis and weaker hydrophobicity of Im ligand, Cu-Im shows the highest electrocatalytic activity with a modest overpotential of 500 mV delivering a current density of 10 mA cm−2 and a Tafel slope of 215 mV dec−1 in 1 M KOH. On the contrary, the hydrophobic and anti-corrosion property of the bIm ligand stabilizes the Cu-bIm during the electrolysis without CuO formation. The hydrophobicity of the coordinating ligand influenced the electrocatalytic activity, resulting in the order of Cu-Im > Cu-mIm > Cu-bIm. Post-reaction analyses of the Cu-imidazolate coordination polymers reveal variations in the oxidation state of Cu, which has not been explored in previous studies. This work underlines that the ligand properties can regulate the catalytic activity of metal-ligand coordination polymer.

Amorphous high-entropy IrRuCrFeCoNiOx as efficient water splitting oxygen evolution reaction electrocatalysts

The process of oxygen evolution reaction (OER) for water splitting is intricate and demands a substantial amount of energy. It necessitates the utilization of catalysts that are both highly efficient and durable in order to overcome the slow reaction kinetics. Amorphous, high-entropy oxide nanoparticles were prepared using simple one-step coprecipitation in this work. Due to highly disordered atomic arrangement in the amorphous structure of these catalysts and their high specific surface area, they compete to form active sites in the OER. Among them, IrRuCrFeCoNiOx demonstrated the optimal OER catalytic activity, requiring just a low overpotential (190 mV) with minimal Tafel slope (51.1 mV dec−1) to achieve the current density of 10 mA cm−2 in 1 M KOH. Through surface self-reconstruction in the OER, a crystalline active layer with a thickness of several nanometers formed on the catalyst’s surface. The stable core-shell nanoarchitectures composed of crystalline and amorphous regions substantially improved the stability of the catalyst. This work verified the effectiveness of high-entropy design and the significant improvement of noble metal doping on OER performance. It develops a new OER catalyst for water splitting with great activity and stability.

NiFe2O4/Ni2P Mott-Schottky heterojunction boosts the oxygen evolution reaction in alkaline water/natural seawater

Exploiting non-noble metal electrocatalysts for sluggish anodic oxygen evolution reaction (OER) is an essential propellant to clean hydrogen energy production from water/seawater electrochemical splitting, but still confronts a grand challenge. Recently, the metal/semiconductor interface effect has been used as a feasible implementation to achieve favorable electrocatalytic performance due to the built-in electric field. Herein, we first report the Mott-Schottky heterojunction electrocatalyst composed of metallic Ni2P and p-type semiconducting NiFe2O4, developed via a two-step hydrothermal-phosphorization method. With the strategy, the catalyst charge redistribution is owning to the self-driven electron carriers transfer in the heterointerfaces of NiFe2O4/Ni2P, leading to the formation of a built-in electric field, thereby favoring the reaction kinetics of OER. Experimental findings that NiFe2O4/Ni2P shows excellent wettability, corrosion resistance, and exceptional OER performance with a low overpotential of 230/260 mV to deliver a current density of 10 mA cm−2, and a low Tafel slope of 53.6/70.8 mV dec−1 in basic solution and natural seawater, respectively. Impressively, the NiFe2O4/Ni2P||Pt/C electrolyzer only needs 1.46/1.56 V to output 10 mA cm−2 and superior stability in water/seawater electrolyte for continuous working for 50 h NiFe2O4/Ni2P Mott-Schottky heterojunction is a promising candidate as a highly efficient OER electrocatalyst for realistic alkaline water/seawater electrolysis.

Multiple oxyanions modification on nickel–iron layered double hydroxides for enhanced oxygen evolution reaction

The electrochemical oxygen evolution reaction (OER) holds paramount significance as a pivotal stage within electrochemical water-splitting processes, particularly in hydrogen production. Highly efficient OER electrocatalysts with inherent capability to effectively lower the energy barrier and promote fast kinetics are in high demand. In this research, we have introduced a novel strategy of modifying the non-precious metal benchmark catalyst, NiFe layered double hydroxide (LDH), through multiple oxyanions. Our approach involved incorporating MoS42− as a source of modified anions to enhance the performance of LDH in OER. Under specific conditions of the hydrothermal reaction, a majority of the sulfur (S) within the MoS42− anions underwent oxidization, resulting in the formation of SO42− and MoOxS4-x2- groups. As a result, NiFe LDH composites that were modified with multiple oxyanionic moieties, were successfully fabricated. Thanks to the synergistic effects of these oxyanions, which accelerate the generation of active NiOOH species, the optimized NiFe LDH-MoS4-0.1/NF sample exhibited a significantly low overpotential of 228 and 270 mV at current densities of 10 and 100 mA cm−2, respectively, along with a low Tafel slope of 35.5 mVdec−1 in 1 M KOH electrolyte solution. Our study underscored the importance of embracing diverse oxyanions modification strategy to amplify the performance of OER, opening up numerous opportunities for energy conversion and storage applications.

Room-Temperature Synthesis of Carbon-Nanotube-Interconnected Amorphous NiFe-Layered Double Hydroxides for Boosting Oxygen Evolution Reaction.

The oxygen evolution reaction (OER) is a key half-reaction in electrocatalytic water splitting. Large-scale water electrolysis is hampered by commercial noble-metal-based OER electrocatalysts owing to their high cost. To address these issues, we present a facile, one-pot, room-temperature co-precipitation approach to quickly synthesize carbon-nanotube-interconnected amorphous NiFe-layered double hydroxides (NiFe-LDH@CNT) as cost-effective, efficient, and stable OER electrocatalysts. The hybrid catalyst NiFe-LDH@CNT delivered outstanding OER activity with a low onset overpotential of 255 mV and a small Tafel slope of 51.36 mV dec-1, as well as outstanding long-term stability. The high catalytic capability of NiFe-LDH@CNT is associated with the synergistic effects of its room-temperature synthesized amorphous structure, bi-metallic modulation, and conductive CNT skeleton. The room-temperature synthesis can not only offer economic feasibility, but can also allow amorphous NiFe-LDH to be obtained without crystalline boundaries, facilitating long-term stability during the OER process. The bi-metallic nature of NiFe-LDH guarantees a modified electronic structure, providing additional catalytic sites. Simultaneously, the highly conductive CNT network fosters a nanoporous structure, facilitating electron transfer and O2 release and enriching catalytic sites. This study introduces an innovative approach to purposefully design nanoarchitecture and easily synthesize amorphous transition-metal-based OER catalysts, ensuring their cost effectiveness, production efficiency, and long-term stability.

Precise Anchoring of Fe Sites by Regulating Crystallinity of Novel Binuclear Ni-MOF for Revealing Mechanism of Electrocatalytic Oxygen Evolution.

Bimetallic metal-organic framework (BMOF) exhibits better electrocatalytic performance than mono-MOF, but deciphering the precise anchoring of foreign atoms and revealing the underlying mechanisms at the atomic level remains a major challenge. Herein, a novel binuclear NiFe-MOF with precise anchoring of Fe sites is synthesized. The low-crystallinity (LC)-NiFe0.33 -MOF exhibited abundant unsaturated active sites and demonstrated excellent electrocatalytic oxygen evolution reaction (OER) performance. It achieved an ultralow overpotential of 230mV at 10mAcm-2 and a Tafel slope of 41mVdec-1 . Using a combination of modulating crystallinity, X-ray absorption spectroscopy, and theoretical calculations, the accurate metal sequence of BMOF and the synergistic effect of the active sites are identified, revealing that the adjacent active site plays a significant role in regulating the catalytic performance of the endmost active site. The proposed model of BMOF electrocatalysts facilitates the investigation of efficient OER electrocatalysts and the related catalytic mechanisms.

PW6Mo6/ZIF-67@NF composite with exposed Co nodes as efficient oxygen evolution reaction electrocatalyst

The construction of efficient, sustainable, and low-cost nonprecious metal electrocatalysts for oxygen evolution reaction (OER) is necessary for the realization of electrocatalytic overall water splitting. Herein, the PW6Mo6/ZIF-67@NF is prepared using a simple coprecipitation method. Characterization results indicate that the PW6Mo6 induces the exposure of Co nodes in ZIF-67, which can act as catalytic active sites for OER. Meanwhile, the introduction of PW6Mo6 improves the conductivity and electrochemical active surface area of ZIF-67, which further enhances the OER performance. The electrochemical test results show that the PW6Mo6/ZIF-67@NF exhibit an ultralow overpotential of 201 mV at 10 mA cm−2 and a small Tafel slope of 55 mV dec−1 for OER, which is lower than that of ZIF-67@NF (329 mV, 286 mV dec−1). Our study demonstrates the potential of polyoxometalate and ZIF composites to decrease the barriers of OER and provides a feasible approach for exploring economical and practical electrocatalysts.

Cu-doping: Accelerated in-situ electrochemical conversion of metal-organic frameworks for efficient electrocatalytic oxygen evolution

Traditional oxygen evolution reaction (OER) electrocatalysts such as IrO2 and RuO2 suffer from high costs and susceptibility to poisoning. Therefore, low-priced, efficient, and stable alternatives urgently need to be developed. In this work, Cu-doped Co metal-organic framework (MOF) was constructed by a one-step solvothermal method, exhibiting excellent OER activity in 1 M KOH with a low overpotential of 235 mV at 10 mA cm−2 and long-term electrochemical durability for 24 h. The mechanism study showed that the amorphous CoOOH formed by in-situ conversion of MOF structure in the electrochemical water oxidation environment was the real active species. The introduction of Cu significantly changed the morphology and surface electronic structure of Co-MOF-74, facilitated the adsorption of water molecules and accelerated the in-situ conversion of Co3Cu-MOF-74 to CoOOH, resulting in improved OER performance. Our work provides new insights into the design of efficient OER electrocatalysts and the mechanistic understanding of MOF-derived electrocatalysts.

Revealing the effect of crystallinity and oxygen vacancies of Fe-Co phosphate on oxygen evolution for high-current water splitting

Strategically tuning the composition and structure of transition metal phosphates (TMPs) holds immense promise in the development of efficient oxygen evolution reaction (OER) electrocatalysts. However, the effect of crystalline phase transformation for TMPs on the catalytic OER activity remains relatively uncharted. In this study, we have deftly orchestrated the reaction process of anion-etched precursor to induce the amorphization process of FeCo-POx from crystalline to amorphous states. The as-obtained amorphous FeCo-POx (A-FeCo-POx) exhibited an optimized OER performance with a low overpotential of 270 mV at a current density of 10 mA cm−2, which could be attributed to the flexibility of its amorphous structure and the synergistic effect of oxygen vacancies. Moreover, when incorporated into an overall water splitting (OWS) device configured as A-FeCo-POx(+)||Pt/C(–), it displayed long-term solid stability, sustaining operation for 300 h at a current density of 200 mA cm−2. This work not only provides valuable insights into understanding the transformation from crystalline to amorphous states, but also establishes the groundwork for the practical utilization of amorphous nanomaterials in the field of water splitting.

Regulating Pt electronic properties on NiFe layered double hydroxide interface for highly efficient alkaline water splitting

Developing cost-effective and highly efficient oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) electrocatalysts is imperative for catalyzing water electrolysis. In this study, significant change in Pt electronic properties was conducted on NiFe layered double hydroxide (NiFe-LDH) by simply regulating the order of boron-modification and Pt-deposition, thereby achieving two electrocatalysts of B-Pt-NiFe-LDH with major Pt0 species and Pt-B-NiFe-LDH with Pt2+ species as the main component, respectively. Interestingly, the B-Pt-NiFe-LDH electrocatalyst displays better alkaline OER performance with a smaller overpotential (208 mV) at 100 mA cm−2 than Pt-B-NiFe-LDH (229 mV), while the Pt-B-NiFe-LDH electrocatalyst shows superior alkaline HER performance with only 19 mV overpotential at 10 mA cm−2 compared with that of B-Pt-NiFe-LDH (65 mV) and Pt-NiFe-LDH (28 mV). The corresponding electrolyzer of B-Pt-NiFe-LDH//Pt-B-NiFe-LDH in 1 M KOH requires only a very low voltage of 1.475 V to deliver 10 mA cm−2 with good durability (110 h), which exceeds the performance of the widely studied RuO2//Pt/C cell (1.516 V). Density functional theory (DFT) calculations suggest that the Pt0 species on NiFe-LDH can lower the energy barrier for OER, while the Pt2+/4+ components are beneficial for HER. This work demonstrates the rational strategy to regulate electronic properties on electrocatalysts for highly efficient water-splitting.

Cobalt-based MOF-derived carbon electrocatalysts with tunable architecture for enhanced oxygen evolution reaction

Development of the hydrogen economy requires the design of catalysts that increase the rate of the accompanying sluggish kinetic oxygen evolution reaction (OER). This is a key process in electrochemical energy conversion and storage, such as water splitting and metal-air batteries. The OER needs high overpotential and typically expensive precious metal-based catalysts. Therefore, designing low-cost and efficient electrocatalysts for OER is of paramount importance. In addition to focusing on the number of active sites or high specific surface area, the correlation between catalyst particle shape and performance should be considered. This work presents an electrocatalytic activity comparison of cobalt-containing carbons with different morphologies in the OER process. Employing metal–organic frameworks as carbon and metal precursors, the materials in the shape of polyhedrons, needles, unique spherical hedgehogs, and sea urchins were obtained. The effect of MOF template infiltration with additional carbon source on the physicochemical properties of electrocatalysts was also examined. The furfuryl alcohol-impregnated needle-shaped particles were characterized by a high content of cobalt active sites, surrounded by nitrogen-containing graphite layers. Electrochemical tests confirmed their best activity (overpotential 317 mV@10 mA/cm2), long stability (up to 20 h), as well as low reagents diffusion limitations (Tafel slope 57 mV/dec up to 24 mA/cm2). The vertically aligned structure of the catalyst contributed to improved detachment of the oxygen bubbles produced.

High-value utilization of Cr-containing sludge: Eco-friendly and ultra-low-cost electrocatalyst for efficient OER in alkaline media from Cr-containing sludge

Economically sustainable development requires more viable waste recycling solutions. In this context, we address the problem of utilizing chromium-containing sludge, a prevalent and environmentally hazardous waste. Meanwhile, sustainable energy development must develop ecology-friendly and low-cost electrocatalysts for the oxygen evolution reaction (OER) in alkaline media. Herein, we report an ultra-low-cost electrocatalyst from chromium-containing sludge. The optimum preparation conditions are determined by optimizing the calcination temperature and the loading of nickel acetylacetonate. The optimized catalyst delivers excellent stability and outstanding OER activity with overpotentials of 320 mV at 10 mA cm−2 in alkaline media. Density functional theory calculations reveal that the energy barrier of OER is decreased because of the catalyst's heterogeneous structure arrangement and confirm the influence of chromium on performance improvement. The concept of “turning waste into treasure” stimulates the search for methods to process Cr-containing waste and produce low-cost, high-performance electrocatalysts.

Construction of Fe-doped Co3S4 nanosheets on Ni Foam as an efficient OER electrocatalyst

Oxygen evolution reaction (OER) is a complex four-electron coupled process, which significantly impacts the efficiency of the electrocatalytic reaction. Design and preparation of cost-effective and binder-free OER electrocatalysts are essential to improving catalytic efficiency. In this paper, Fe-doped Co3S4 nanosheets have been directly deposited on nickel foam (NF) and applied to OER. Due to the synergy arising from the augmentation of active sites and charge transfer efficiency, Fe-Co3S4/NF exhibits excellent OER electrocatalytic activity. The overpotential of 242 mV and a Tafel slope of 50.5 mV dec−1 at a current density of 10 mA cm−2 was achieved in 1.0 M KOH solution, which was lower than commercial RuO2. Fe-Co3S4/NF electrode also exhibits long-term stability, maintaining a consistent current density over a 20-hour testing period. This makes Fe-Co3S4/NF electrode has potential utilization in industrial applications.

Oxygen evolution catalyzed by Ni-Co-Nb ternary metal sulfides on plasma-activated Ni-Co support

As a four-electron–proton coupled reaction, the oxygen evolution reaction (OER) requires a high overpotential for electrocatalytic water splitting. Most of the reported OER catalysts still need higher overpotentials than the thermodynamic water decomposition potential (1.23 V). Therefore, developing the efficient and cost-effective OER electrocatalysts remains a challenge in the electrocatalysis filed. Herein, multiphase Ni-Co-Nb sulfides (NiCoNbSx) are in-situ engineered on the plasma-activated nickel–cobalt foam (PNCF), and the synthesized NiCoNbSx/PNCF exhibits rich heterointerfaces and active sites, causing a high OER performance in an alkaline medium. The NiCoNbSx/PNCF catalyst features the low overpotentials of 48 and 382 mV for delivering the current densities of 10 (j10) and 1000 mA cm−2 (j1000), with a good electrocatalytic stability. The theoretical calculations reveal that the heterojunction interface of NiS (401)-Co9S8 (440) acts as the active center for OER. These results provide a new effective surface modification approach and insights into catalytic processes enabling water electrolysis pursued for clean and sustainable energy applications.

Deciphering the Space Charge Effect of the CoNiLDH/FeOOH n-n Heterojunction for Efficient Electrocatalytic Oxygen Evolution.

Space charge transfer is an effective strategy to regulate the electron density of narrow bandgap semiconductors for enhancing electrocatalytic activity. Herein, the CoNiLDH/FeOOH n-n heterojunction hollow nanocages structure is constructed. The hollow structure provides abundant catalytic active sites and enhances mass transfer. The space charge region in the n-n heterojunction significantly promotes the adsorption of OH- and electron transfer; and the built-in electric field accelerates the electron transport, optimizes the electronic structure during the catalytic reaction process, and ensures the stability of surface charged active center sites in the heterojunction. Thus, CoNiLDH/FeOOH delivers an excellent oxygen evolution reaction (OER) overpotential of 250mV to achieve a current density of 10mA cm-2 with a small Tafel slope of 60mV dec-1 , and superior electrocatalytic durability for 210h at a high current density. Density functional theory calculations further verify that the space charge effect and built-in electric field in the n-n heterojunction of CoNiLDH/FeOOH can improve the electron transfer and lower the adsorption energy of OH- and the reaction energy barrier of the rate-determining step. This work provides a new fundamental understanding of the space charge effect of semiconductor heterojunction during the electrocatalytic process for developing more efficient OER electrocatalysts.

Enhancement of electrocatalytic performance of Janus In2SSe monolayer for oxygen evolution reaction by the introduction of N

Non-metallic atom doping as efficient oxygen evolution reaction (OER) electrocatalysts has attracted much interest. In this work, the feasibility of N doped Janus In2SSe monolayers as an OER electrocatalyst is systematically investigated using first-principles calculations. The results suggest that the N substitution with high spin states for the S/Se atom in the Janus In2SSe monolayer can effectively enhance the electrocatalytic reactivity of adsorbed intermediates. The NS-In2SSe monolayer exhibit outstanding OER catalytic performance with small overpotential of 0.687 V. Moreover, the strong atomic interactions between the N dopant and intermediates can be contributed to the hybridization between the O- and N-p orbitals. Through the analysis of crystal orbital Hamilton population (COHP), the adsorption strength of OH species on the NS-In2SSe monolayer is stronger than that on the NSe-InSe monolayer, leading that the NS-In2SSe monolayer possesses a higher OER electrocatalytic activity. The fourth electron reaction step becomes exothermic when the real solution environment is considered, meaning that the desorption of O2 becomes easier under aqueous solution conditions. This work demonstrates the possibility of N doped Janus In2SSe monolayer as electrocatalyst and also offers new insights into designing SACs constructed by non-metal atoms.

Nanoflower-like FeVNi3S2–x as efficient electrocatalyst for alkaline oxygen evolution reaction

The development of low cost efficient catalysts for oxygen evolution reaction (OER) is still a obstacle to realize the commercialization of electrocatalytic water splitting. Herein, interface engineering and heteroatom doping is adopted to synthesize iron and vanadium doped nickel sulfide on nickel foam via hydrothermal method followed by hydrogen treatment to create sulfur defects. The optimized nanoflower-like FeVNi3S2–x /NF is an efficient OER electrocatalyst that outperforms many of the reported transition metals catalysts. Benefiting from abundant sulfur defects and the synergistic effect of heteroatom doping, FeVNi3S2–x /NF exhibits an ultralow overpotential of 230 mV to reach a current density of 100 mA cm−2, a rapid reaction kinetics with a small Tafel slope of 46.6 mV dec−1, and a stable long-term durability in 1 M KOH. Experimental results and characterizations confirm that sulfur vacancies together with the synergistic effect from multiple heteroatom doping can effectively regulate the electronic structure, resulting in increased electrical conductivity and electrochemically active surface area, thus enhancing OER performance. Furthermore, in situ Raman spectroscopy reveals that, the reconstitution amorphous nickel oxyhydroxide (NiOOH) on the catalyst surface is responsible for catalyzing the OER reaction. This work represents a promising methodology to synthesize low-cost and highly active OER electrocatalysts.

Scalable synthesis of MOF-derived Nd2O3@C and V2O5@C nanohybrid: Efficient electrocatalyst for OER in alkaline medium

Craving to search for renewable energy reservoirs for the development of green and robust electrocatalysts, now become essential for catalytic performance by using energy conversion devices. Herein, we fabricated a metal–organic framework (MOF) derived transition metal and rare earth metal oxides-based materials for water electrocatalysis. MOF is regarded as the potential hotspot to increase catalytic activity through fascinating chemical and structural traits. This study summarizes the oxygen evolution reaction (OER) of MOF-derived Nd2O3@C and V2O5@C by depositing them on stainless steel substrate (SS) in an alkaline medium. The grown electrocatalysts Nd2O3, V2O5, Nd-MOF, V-MOF, and MOF-derived Nd2O3@C and V2O5@C probed by various useful techniques to confirm oxidation states, phase-changing, structural, morphological, and compositional properties. The MOF-derived Nd2O3@C and V2O5@C formed irregular spherical shaped and nanorod-like morphology, respectively, which proved helpful for the easy transfer of electrons to enhance OER. The electrochemical study indicates that among all electrocatalysts, the V2O5@C electrode exhibits remarkable electrochemical results having low overpotential (282 mV), and smaller Tafel slope of 60 mVdec-1 at a current density of 10 mAcm−2, exhibiting that the transition metal based MOF has good efficiency as compared to the rare earth metal MOF. The grown catalysts enable additional reaction sites and open up new channels, besides it approaches quick electron transfer in V2O5@C through a carbon bridge. Thus, the porous skeleton of the resulting hybrid catalyst showed superior electrical conductivity, boosting electrochemical properties and making it an efficient and durable electrocatalyst for industrial-scale water electrolysis.

Reusing waste plastic bottle to reduce MoO3 into carbon-supported MoO2 nanoparticles for efficient water electrolysis

One of the efficient ways to produce hydrogen through electrolysis of water is oxygen evolution reaction (OER). OER being an anodic process requires highly efficient, sustainable and economic electrocatalysts with long term stability. In this work, plastic water bottle is utilized as a carbon source and a reducing agent to reduce MoO3 to carbon supported MoO2 (MoO2@C) as an efficient electrocatalyst for OER. The conductive carbon layers encapsulating the MoO2 nanoparticles enhances the charge transfer rate and improves the long-term stability. The defect rich supporting carbon exhibits high specific surface area and improves the electrochemical activity of MoO2 nanoparticles. The sample requires only an overpotential of 516 mV (vs. Ag/AgCl) to achieve a current density of 10 mA cm-2 and a low Tafel slope of 84.4 mV dec−1. It displays excellent electrochemical stability up to 2000 cyclic voltammetry (CV) cycles and revealed excellent stability up to 24 h. The reported method provides an efficient way to reuse waste plastic bottle to as carbon source as well as reducing agent produce MoO2@C electrocatalyst at an industrial scale.