OER Performance Research Articles

Deciphering the Role of Second Metal in M-Ni (M = Fe, Ni, and Mn) Heterobimetallic Electrocatalysts in Controlling the HAT versus Hydride Transfer Mechanism for the Dehydrogenation of Alcohols.

The second 3d-transition metal incorporation in Ni-(oxy)hydroxide has a drastic effect on alkaline OER and alcohol dehydrogenation reactivity. While Mn incorporation suppresses the alkaline OER, it greatly improves the alcohol dehydrogenation reactivity. A complete reversal of reactivity is obtained when Fe is incorporated, which shows better performance for alkaline OER with poor alcohol dehydrogenation reactivity. The role of the second 3d-metal is elusive due to the lack of systematic mechanistic studies. In this report, we thoroughly analyzed a series of M─Ni (M = Fe, Ni, Mn) (oxy)hydroxides derived from electrochemical activation of M-MOF grown on nickel foam for its electrochemical activity in alkaline OER and aliphatic, benzyl alcohol dehydrogenation. With the help of pH-dependence and kinetic isotope effect studies, the potential-determining step (PDS) and the rate-determining step (RDS) have been elucidated. The Hammett analysis revealed critical information about the transition state and offered insight into the hydrogen atom transfer (HAT) versus hydride transfer (HT) for alcohol dehydrogenation operative in various heterobimetallic electrocatalysts. Further, the superior alcohol dehydrogenation reactivity of NiMn catalyst for PET hydrolysate electro-oxidation is extended to afford valuable chemicals with concomitant production of hydrogen.

Taking Advantage of Activation Potential Coincidence to Unlock Stable Direct Seawater Splitting

AbstractElectrochemical seawater splitting faces competing chlorine evolution reactions and chlorine corrosion, proposing significant obstacles to commercial applications. In this work, a feasible strategy is developed for the simultaneous oxidation of SO42− and CoFe LDH to form an intercalation SO42−/CoFe LDH, which achieves excellent OER performance (265.2 mV@100 mA cm−2) and satisfactory stability (1000 h@500 mA cm−2). The presence of SO42− is found to enhance the intrinsic activity of CoFe LDH and reduce the corrosion tendency of CoFe LDH. In situ Raman and selected area electron diffraction results demonstrated that CoFe LDH and SO42− are simultaneously generated and inserted into the LDH interlayer. DFT calculations further confirmed that the insertion of SO42− reduced the tendency of Cl− adsorption, which improved the OER selectivity. Finally, in the flow AEM electrolyzer, the SO42−/CoFe LDH and Pt/C system exhibited a voltage of only 2.264 V at 500 mA cm−2 and achieved stable operation in natural seawater for 150 h. The working efficiency in natural seawater is as high as 55.0% with the price per GGE H2 as low as $1.211, which is promising for a wide range of applications.

Investigation of the Synergistic Effect of Doping and Composite Formation on Electrochemical OER Performance of g-C3N4 for Sustainable Energy

Investigation of the Synergistic Effect of Doping and Composite Formation on Electrochemical OER Performance of g-C₃N₄ for Sustainable Energy

Big pyridyl Schiff base π-conjugated skeleton based cobalt/iron metal complexes: bimetallic electrocatalysts for the oxygen evolution reaction

Cobalt/iron-based redox-active pyridyl Schiff base metal complexes were synthesized simply. The optimized Co3FePM-TPDA showed good OER performance and stability, even in simulated seawater.

Ultrafast synthesis of tetragonal-distorted FeCoNiCuCr high-entropy alloy nanoparticles for enhanced OER performance

Ultrafast synthesis of tetragonal-distorted FeCoNiCuCr high-entropy alloy nanoparticles for enhanced OER performance

Pyrenetetrasulfonic Acid Tetrasodium Salt‐Modified CoFe Layered Double Hydroxide Enables Stable Alkaline Seawater Oxidation

AbstractSeawater electrolysis is deemed a green and promising technology for producing hydrogen in coastal areas. Nevertheless, ample chloride ions (Cl–) in seawater can corrode anode, especially at ampere‐level current densities (j), which represents a significant impediment to the seawater‐to‐H2 system. In this study, we present a CoFe layered double hydroxide nanoneedle array modified with 1,3,6,8‐pyrenetetrasulfonic acid tetrasodium salt (PTS) on Ni foam (CoFe LDH@CoFe‐PTS/NF) as a highly efficient electrocatalyst for seawater oxidation. It reveals that PTS with a large negative charge density can effectively repel Cl– and keep active sites working stably during alkaline seawater oxidation. Thus, CoFe LDH@CoFe‐PTS/NF demonstrates excellent OER performance and can achieve j of 500 and 1000 mA cm−2 at low overpotentials (η) of 333 and 364 mV. Moreover, it maintains a stable and continuous electrolysis for 500 h with minimal amounts of active chlorine generation.

Interfacial engineering of NiS/NiMoO4 nanorod arrays to improve OER and HER performance for stable overall water splitting

Interfacial engineering of NiS/NiMoO4 nanorod arrays to improve OER and HER performance for stable overall water splitting

Atmosphere-driven oriental regulation of Ru valence for boosting alkaline water electrolysis

Modulating the electronic characteristics of nanomaterials has been key to advancing sustainable energy technologies. In this study, we controlled the Ru electronic properties of NiRuOx by varying the calcination atmospheres (Air and Argon), resulting in two distinct electrocatalysts: NiRuOx-O2 with Ru4+ species and NiRuOx-Ar with Ru0 species as the main component. We established the relationship between the valence of Ru and its HER and OER catalytic activity as NiRuOx for example. Specifically, NiRuOx-Ar with metallic Ru demonstrates better alkaline HER activity with a smaller overpotential (94 mV) at 100 mA cm−2 than NiRuOx-O2 with Ru4+ due to the reduced Ru0 superiority towards H*. Conversely, NiRuOx-O2 shows superior alkaline OER performance with only 275 mV overpotential at 100 mA cm−2 compared with that of NiRuOx-Ar (383 mV) due to Ru4+ receiving electrons from Ni species and reduced Ru–O covalence. The NiRuOx-O2//NiRuOx-Ar electrolyzer in 1 M KOH achieves 10 mA cm−2 at 1.475 V with 100 h durability, surpassing the RuO2//Pt/C cell (1.516 V). Revealing the correlation between Ru valence and activity offers important insights for the rational design of Ru-based catalysts for HER and OER.

Enhancing electrochemical performance of Co3O4/ZnO composite nanostructures through interface engineering for oxygen evolution reaction

Co3O4/ZnO composite nanostructures were successfully synthesized via a simple hydrothermal method followed by air-based calcination at 500°C. The resulting hexagonal heterostructure composite with a large interfacial area demonstrates exceptional oxygen evolution electrocatalytic activity with an overpotential of 288 mV at 10 mA cm-², and a low Tafel slope (80 mV dec⁻¹). This enhanced activity is attributed to the Co3O4/ZnO p-n junction, where ZnO (an n-type semiconductor) and Co3O4 (a p-type semiconductor) meet, which is crucial for boosting catalytic activity. This interface enables swift electron movement between the two materials, resulting in better charge separation and decreased charge recombination. Additionally, the high active surface area, confirmed by cyclic voltammetry measurements, further contributes to the improved OER performance. The well-defined interfaces within the Co3O4/ZnO heterostructures provide abundant active sites, facilitating efficient charge transfer kinetics. This research highlights the potential of composite heterostructures as promising electrocatalysts for water-splitting applications.

Coordination engineering of B/N-doped graphene with phosphorus-transition metal diatomic catalysts for enhanced oxygen bifunctionality electrocatalysis

The design of highly active and cost-effective bifunctional catalysts for oxygen evolution (OER) and oxygen reduction (ORR) reactions is critical for advancing energy storage and conversion, yet significant challenges remain. Inspired by the efficient bifunctionality of graphene-based single-atom and diatomic catalysts in OER/ORR, we designed 42 structural of TMPX4@graphene (X = B, N; TM = V-Pt) and A-BN, and assessed their OER and ORR catalytic performance using density functional theory (DFT). The sum of overpotentials (ηsum = ηOER + ηORR) was identified as an effective descriptor for predicting the bifunctional catalytic properties of the TMPX4@graphene system. The transferred electron count and d-orbital occupation of Co atoms were identified as key sources of catalytic activity in OER and ORR, as determined through Bader charge analysis and partial density of states (PDOS). Finally, constant potential method (CPM) calculations showed that CoPB4@graphene exhibits excellent catalytic activity under alkaline conditions, with ORR and OER overpotentials of 0.86 V and 1.38 V, respectively. This study highlights the importance of rationally designing the local coordination environment by regulating boron content to enhance catalytic activity. It further provides insights into the rational design of stable and efficient catalysts by considering electrode potential and pH effects in electrocatalytic systems.

High stability cubic perovskite Sr0.9Y0.1Co1-xFexO3-δ oxygen evolution by phase control and electrochemical reconstruction

Transition metal oxides are considered ideal electrocatalyst materials due to their low cost and high intrinsic activity. Among them, SrCoO3-δ has received increasing attention due to its multi-phase structure and tunable electronic properties, though its OER reaction kinetics and catalysis stability are unsatisfactory. Herein, based on a simple one-step solid-state reaction method, we use a small amount of rare earth Y ions (10 %) to transform H-SCO2.52 from a hexagonal structure to a stable cubic perovskite Sr0.9Y0.1CoO3−δ. While broadening the atomic ratio of Co and Fe in the B-site under the cubic perovskite Sr0.9Y0.1Co1-xFexO3−δ (x = 0–1), the relationship between the B-site electronic state, oxygen vacancies, and OER performance has been explored. Sr0.9Y0.1Co0.2Fe0.8O3−δ with a high concentration of oxygen vacancies, exhibits the lowest overpotential of 277 mV and maintains stability at 10 mA cm−2 for 88 h. The valence states of Fe and Co atoms in SYC0.2F0.8 O are optimized (Fe2+∼50.81 %, Co2+∼19.39 %), and the oxygen evolution activity is enhanced by electrochemical reconfiguration to form high-valence Fe and Co ions. Selective leaching of Sr ions via electrochemical surface reconstruction activates FeOOH and CoOOH amorphous layer active sites on the catalyst surface, significantly enhancing reaction kinetics.

Unveiling the Structure-Activity Relationship for Cobalt-Based Spinel Oxide with Superior Acidic Oer Performance

Climate change has become an urgent issue due to the high carbon emission from various industrial sectors. As a result, achieving carbon neutrality has become a priority for society. Hydrogen is widely used in various industries and stands out as a promising zero-carbon energy carrier. However, most hydrogen is currently produced from steam reforming of natural gas, which is unsustainable due to its consumption of fossil fuel and the enormous amount of COx and NOx by products released. Water electrolysis presents an attractive alternative for clean hydrogen production when coupled with renewable electricity. In recent years, the proton exchange membrane water electrolyzer (PEMWE) has received significant attention due to its ability to produce hydrogen at high rate, high efficiency, and high purity. The current bottleneck of PEMWE technology comes from its reliance on pricey Ru or Ir-based catalysts with limited durability. Thus, finding a low-cost catalyst with high activity and stability for the acidic oxygen evolution reaction (OER) on the anode is crucial for the next generation PEMWE products.Co3O4, as an alternative to Ru and Ir-based catalysts, has attracted much attention due to its low cost, good activity, and acid tolerance. A significant amount of effort has been devoted to further improving the performance of Co3O4 and related spinel oxides, in order to reach the superior performance of noble-metal-based catalysts1. However, the maintenance of both high activity and acid corrosion resistivity has remained challenging. These two factors are closely related to the OER reaction mechanism, and direct oxo coupling (DOC) has been proposed as an ideal mechanism that optimizes both activity and stability2. Nevertheless, the DOC mechanism requires tight control of lattice parameters and metal site distances3,4, consequently non-noble-metal-based spinel oxide structures that enable acidic OER via the DOC mechanism have not been reported.In this work, we present a facile method of hydrothermal synthesis that produces aggregated needle-like spinel NiCo2O4 nanostructures. In 0.5M H2SO4, the NiCo2O4 nanostructure exhibits remarkable activity and record-high durability for acidic OER. In-situ x-ray absorption spectroscopy revealed a higher stability during acidic OER catalysis of the Co and Ni coordination environment in NiCo2O4 compared to its less stable Co3O4 counterpart. This observation indicates the formation of fewer oxygen vacancies on NiCo2O4 under reactive potential, avoiding the critical structural deformation that would impair catalyst durability. Furthermore, we conducted density functional theory calculations to confirm the decreased OER overpotential arising from replacement of Co with Ni in octahedral lattice sites and to learn the preferred reaction pathway for DOC.In conclusion, this research presents NiCo2O4 as an acidic OER catalyst with superior activity and stability. This investigation into NiCo2O4 provides insights into the design of anode catalysts for PEMWE, advancing toward sustainable hydrogen production with high yield and low cost.References Yang, X.; Li, H.; Lu, A.-Y.; Min, S.; Idriss, Z.; Hedhili, M. N.; Huang, K.-W.; Idriss, H.; Li, L.-J., Highly acid-durable carbon coated Co3O4 nanoarrays as efficient oxygen evolution electrocatalysts. Nano Energy 2016, 25, 42-50.Wang, L.-P.; Van Voorhis, T., Direct-Coupling O2 Bond Forming a Pathway in Cobalt Oxide Water Oxidation Catalysts. The Journal of Physical Chemistry Letters 2011, 2 (17), 2200-2204.Fang, Y.-H.; Liu, Z.-P., Mechanism and Tafel Lines of Electro-Oxidation of Water to Oxygen on RuO2(110). Journal of the American Chemical Society 2010, 132 (51), 18214-18222.Lin, C.; Li, J.-L.; Li, X.; Yang, S.; Luo, W.; Zhang, Y.; Kim, S.-H.; Kim, D.-H.; Shinde, S. S.; Li, Y.-F.; Liu, Z.-P.; Jiang, Z.; Lee, J.-H., In-situ reconstructed Ru atom array on α-MnO2 with enhanced performance for acidic water oxidation. Nature Catalysis 2021, 4 (12), 1012-1023.

Versatile platform of 3D/2D/1D:ZnFe2O4/NiAl-LDH/MWCNTs nanocomposite for photocatalytic purification of dinoseb and electrocatalytic O2 evolution reaction

Integrating photocatalysis with electrocatalysis may represent a synergistic approach to address environmental and energy challenges. In this context, we explored synthesizing a series of nanocomposite materials using a solid-state approach involving simple grinding and subsequent thermal treatment for the photocatalytic purification of dinoseb and electrocatalytic oxygen evolution (OER). Interestingly, among the series of synthesized materials, 40 wt percentage of 3D/2D/1D:ZnFe2O4/NiAl-LDH/MWCNTs ternary nanocomposite (40-NZM) showed highly improved dinoseb detoxification and OER efficiencies compared to those of pure materials. Importantly, approximately 98% detoxification of dinoseb was observed within 75 min of irradiation time under a visible light source. Remarkably, the 40-NZM nanocomposite exhibited the highest rate constant value (k = 4.1 × 10−2 min−1) with a favorable R2 (0.98) parameter. Furthermore, 40-NZM showed promising electrocatalytic OER performance, requiring only 217 mV of overpotential to achieve 10 mAcm−2 of current density with a smaller Tafel slope of 66.6 mVdec−1. Additionally, long-term stability was tested by recording 2000 cyclic voltammetry (CV) cycles. The results revealed that 40-NZM could maintain its catalytic activity for a longer duration as it required only 227 mV to attain 10 mAcm−2 even after 2000 CV cycles. Consequently, these outstanding characteristics of 40-NZM nanocomposite underscore the significant potential for catalytic water purification and sustainable energy conversion.

Partial Selenization Strategy for Fabrication of Ni0.85Se@NiCr-LDH Heterostructure as an Efficient Bifunctional Electrocatalyst for Overall Water Splitting.

NiCr-LDH and its partial selenization as Ni0.85Se@NiCr-LDH heterostructure is established here as an alkaline water electrolyzer for achieving enhanced overall water splitting efficiency. The hydrothermally synthesized optimized batch of Ni0.85Se@NiCr-LDH is thoroughly characterized to elucidate its structure, morphology, and composition. Compared to pristine NiCr-LDH, the batch of Ni0.85Se@NiCr-LDH exhibits exceptional alkaline OER and HER activity with low overpotentials of 258 and 85 mV at 10 mA cm-2, respectively. Besides, Ni0.85Se@NiCr-LDH also exhibits excellent acidic HER with an overpotential of only 61 mV at 10 mA cm-2, indicating that Ni0.85Se@NiCr-LDH can operate effectively across a wide pH range. The excellent electrochemical stability of Ni0.85Se@NiCr-LDH for 24 h operation is attributed to the formation of a thin layer of SeOx during OER operation. The role of selenization and the effect of Cr in the LDH lattice toward enhanced electrocatalytic water splitting is discussed. The outstanding OER and HER performances of Ni0.85Se@NiCr-LDH are attributed to the higher electrochemical active surface area, favorable conditions for adsorption of HER/OER intermediates, low charge transfer resistance, and improved conductivity. The practical application ofNi0.85Se@NiCr-LDHas a bifunctionalelectrocatalyst for overall water splitting is reflected from the low cell voltage of 1.548 V at 10 mA cm-2.

Self-optimizing interface engineering with simultaneous activation of surface lattice oxygen for enhanced electrocatalytic water oxidation

Iron vanadium (FeV)-based bimetallic oxides/hydroxides are promising electrocatalysts for water splitting. However, during the continuous OER process, most FeV catalysts are subjected to violent lattice distortion, resulting in a large amount of VOx dissolved into the electrolyte. Here, we propose an innovative material design strategy that not only replenishes the leaching V site of FeV-LDHs but also promotes the formation of VOOH on the surface, thereby establishing a self-optimizing interfacial interaction between VOOH and FeV-LDHs. The vacancies generated by interfacial rearrangement promote the adsorption of oxygen intermediates, while also contributing to a regulated electronic structure of Fe and V. Moreover, the presence of shared V–O bonds between VOOH and FeV-LDHs serves as an efficient charge transfer pathway, which not only stabilizes the high valence states of V but also enhances the activity of surface lattice oxygen in the OER process. Furthermore, the continuous adsorption of OH− promotes the formation of more oxygen vacancies in the catalyst system, thereby facilitating the deprotonation process and the production of O2. As a result, the VOOH/FeV-LDHs demonstrate exceptional OER performance, requiring a mere 158 and 217 mV overpotential to achieve current densities of 10 and 200 mA cm−2, respectively.

Fe, Mo co-doping enhances the OER performance of nickel sulfide nanoflakes for seawater electrolysis

Development of efficient and corrosion-resistant catalysts for oxygen evolution reaction (OER) offers great promise for seawater electrolysis but remains a challenge. Herein, Fe, Mo-co-doped NiS/Ni3S2 (FeMo-NiSy) rough nanoflakes array on Ni foam has been developed as a high-efficiency OER electrocatalyst for seawater electrolysis. The optimal electrode Fe0.05Mo-NiSy only requires an overpotential of 289 mV to drive 100 mA cm−2 for seawater oxidation, which is 194 mV lower than that of NiSy (483 mV). Based on the experiments and density functional theory (DFT) calculations, the significantly enhanced OER activity can be attributed to the modified electronic structure and the reduced free energy of the potential-limiting step after co-doping of Fe and Mo. Importantly, the Fe0.05Mo-NiSy electrode presents great durability in simulated seawater and natural seawater due to the good corrosion resistance. This study provides new insight into bimetallic co-doping sulfides for seawater oxidation.

Activation of iridium site based on IrO2 catalysts towards highly stable PEM water electrolyzer

The exploitation of anode electrocatalysts with high activity and stability remains an enormous challenge in proton exchange membrane (PEM) water electrolyzer. Here we doped Mn to activate Ir site in IrO2 through the molten salt sealing method, and the optimized Mn0.1Ir0.9O2 exhibited superior OER performance. Mn doping optimized the electronic structure and dominant crystal planes of IrO2, as evidenced by our complementary characterizations. Impressively, the Mn0.1Ir0.9O2 exhibits superior performance in the PEM water electrolyzer, only requiring 1.79 V to attain 1 A cm−2 and offering long-term stability over 1200 h (attenuated only 17.5 μV h−1 compared to 1.27 mV/h for the original sample). DFT calculation shows Mn doping could activate Ir site, thus reducing the energy barrier of the rate-determining step for promoting OER. This work provides a strategy to design high-tolerance catalysts for the PEM water electrolyzer in actual working conditions.

Production of cost-effective green energy using Mn/Gd co-substituted cobalt ferrites hydroelectric cells and their oxygen evolution reaction

A thorough investigation into hydroelectric cells (HECs) composed of spinel ferrites, aiming to generate environmentally friendly electricity through the dissociation of water molecules into H3O+ and OH- ions without producing any harmful by-products has been reported. Utilizing a modified sol-gel auto-combustion synthesis method, we synthesized highly porous Mn2+/Gd3+ co-substituted cobalt ferrites (CFO) with the formula) [Co1-xMnxFe2-yGdyO4, 0≤x≤0.30 and y = 0.10]. X-ray diffraction (XRD) analysis revealed a singular-phase cubic structure, while Rietveld refinement provided essential parameters such as crystallite size, lattice constant, density, porosity percentage, and unit-cell volume. Morphological examination using Field emission scanning electron microscopy (FESEM) confirmed nanoparticle formation with an average size of 60.418 nm, and porosity increasing from 30 % to 51 % with Mn2+ ion doping, indicating enhanced water adsorption. XPS analysis highlighted increased lattice defects due to Mn/Gd co-substitution, boosting water adsorption capacity. Vibrating Sample Measurements showed a rise in Ms value with increasing Mn2+ concentration. Fabricated HECs delivered a maximum output current density of 13.906 mA/cm2, with 20 % Mn-substituted gadolinium cobalt ferrites-based HEC achieved a peak short-circuit current of 9.16 mA. These cells exhibited pseudo-capacitive behaviour, characterized by rapid and reversible faradaic reactions near electrode surfaces, while ionic diffusion mechanisms confirmed ion diffusion over the material's surface. Co1-xMnxGd0.1Fe1.9O4 (x = 0.20) is the optimal composition to get best OER performance having an overpotential of 342 mV at 10 mA/cm2 with a Tafel slope of 48 mV/dec in alkaline medium. This study underscores the potential of Mn2+/Gd3+ co-substituted cobalt ferrite as a promising alternative in green energy conversion applications, potentially replacing conventional fuel and solar cells. It has been concluded that the x = 0.20 is the composition that exhibits the best OER as well as HEC performance.

Ce-doped NiFe-layered-double-hydroxide hierarchical nanocomposite and metal/imidazolate framework carbon nanotube nanocomposite: A bifunctional material for OER electrocatalyst and supercapacitor electrode applications

The development of nanocomposites as electrocatalysts with low cost and high efficiency for OER and as electrode material enhancing the electrochemical performance of supercapacitors are the most popular investigations in this field. Herein, a new bifunctional composite including Ce-doped NiFe-LDH Nanosheets and ZIF-derived carbon base incorporating neodymium and Fe into the structure of Zeolitic Imidazolate Framework is proposed and the construction was through entering Fe-ZIF8@Nd-ZIF67 into the structure of NiFeCe-LDH in different ratios of 10, 20 and 30 %. Various physical and electrochemical tests were conducted to evaluate the nanocomposites. Results indicated that the composite presented a hierarchical porous structure and exhibited outstanding performance for OER and supercapacitor applications. According to the results, the 30 % composite of NiFeCe-LDH/ Fe-ZIF8@Nd-ZIF67 exhibits a superior onset overpotential of 170 mV and an overpotential of 300 mV at a current density of 10 mA·cm−2. Besides, it shows an excellent specific capacitance of 345.36 (F.g−1) at 1 A.g−1. Hence, the synthesized nanocomposite demonstrated outstanding performance in both OER and supercapacitor applications.

The key role of the second material's OER activity on MOR durability enhancement of the Pt alloys

Pt-based precious metal catalysts are generally regarded as the best catalyst materials for direct methanol fuel cells due to their high inherent methanol oxidation (MOR) activity. However, the commercial application of Pt catalyst is still facing with severe durability problem. The CO formed by the incomplete oxidation of methanol will occupy the Pt active site, hindering the further progress of the MOR reaction and causing the rapid attenuation of the activity. In this work, a MOR durability enhancement strategy that relation to the OER performance of the second materials M (M=Ni, Co, Fe and Cu) is reported. The precise electrochemical test results showed that the MOR durability of Pt-M alloy changes with the second material, which is related to the OER activity of M materials. The smaller the overpotential and tafel slopes of the M material, the better the MOR durability. Via M material screening, the Co element with the lowest OER overpotential among M promoted the Pt-Co alloy material with the highest MOR durability, resulting an excellent durability sustain 7000 times CV cycles with just 0.53 A mg−1Pt mass activity loss. According to the current generally accepted OER and MOR reaction mechanism, the association of MOR durability with OER activity is most likely derived from the same reaction step of M-OH formation, which played a key role on both reaction. This relationship between OER overpotential and MOR durability helps to screen the second material from the perspective of OER activity to improve the MOR durability of Pt catalysts, which is of great significance for the development of Pt-based CO-resistant MOR catalysts.