Active Bifunctional Catalysts Research Articles

Promoting Electrocatalytic Oxygen Reactions Using Advanced Heterostructures for Rechargeable Zinc-Air Battery Applications.

In order to facilitate electrochemical oxygen reactions in electrically rechargeable zinc-air batteries (ZABs), there is a need to develop innovative approaches for efficient oxygen electrocatalysts. Due to their reliability, high energy density, material abundance, and ecofriendliness, rechargeable ZABs hold promise as next-generation energy storage and conversion devices. However, the large-scale application of ZABs is currently hindered by the slow kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). However, the development of heterostructure-based electrocatalysts has the potential to surpass the limitations imposed by the intrinsic properties of a single material. This Account begins with an explanation of the configurations of ZABs and the fundamentals of the oxygen electrochemistry of the air electrode. Then, we summarize recent progress with respect to the variety of heterostructures that exploit bifunctional electrocatalytic reactions and overview their impact on ZAB performance. The range of heterointerfacial engineering strategies for improving the ORR/OER and ZAB performance includes tailoring the surface chemistry, dimensionality of catalysts, interfacial charge transfer, mass and charge transport, and morphology. We highlight the multicomponent design approaches that take these features into account to create advanced highly active bifunctional catalysts. Finally, we discuss the challenges and future perspectives on this important topic that aim to enhance the bifunctional activity and performance of zinc-air batteries.

Designing Highly Efficient Electrocatalyst for ORR and OER Based on Nb2CO2 MXene: The Role of Transition Metals and N-Doping Content.

Finding efficient and stable electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is imperative for advancing zinc-air batteries. Herein, the effect of transition metal anchored on Nb2CO2 with different N content to form TM-Nx-Nb2CO2 on the catalytic activity of ORR and OER is investigated by density functional theory. Among all the designed TM-Nx-Nb2CO2, Pt-N12.50%-Nb2CO2, Pt-N37.50%-Nb2CO2, Pt-N50.00%-Nb2CO2, Pd-N68.75%-Nb2CO2, and Pd-N100%-Nb2CO2 are excellent ORR electrocatalysts with ηORR values of 0.38, 0.36, 0.38, 0.38, and 0.34 V, respectively. Rh-Nb2CO2, Rh-N12.50%-Nb2CO2, Rh-N31.25%-Nb2CO2, Rh-N37.50%-Nb2CO2, Rh-N50.00%-Nb2CO2, Pt-N50.00%-Nb2CO2, Rh-N68.75%-Nb2CO2, and Rh-N81.25%-Nb2CO2 are excellent OER electrocatalysts with ηOER values of 0.33, 0.37, 0.34, 0.36, 0.37, 0.34, 0.38, and 0.33 V, respectively. Notably, Rh-Nb2CO2 and Pt-N50.00%-Nb2CO2 exhibit outstanding ORR and OER bifunctional catalytic activity with potential gap values of 0.80 and 0.72 V, respectively, which are higher than the activities of most reported bifunctional catalysts. Furthermore, electronic structure analysis indicates that the moderate adsorption strength of oxygen-containing intermediates on active centers is crucial for achieving highly active bifunctional catalysts for ORR and OER. This study provides a strategy for the design of novel ORR and OER catalysts using 2D MXene materials.

Synergistic enhancement of bifunctional activity and stability of seawater electrolysis by in situ etching and concentration strategies

An effective way to lessen the scarcity of freshwater resources is recognized as seawater electrolysis. Significant importance is attached to developing bifunctional catalysts appropriate for seawater electrolysis in industrial settings. In situ, etching and electrodeposition on nickel foam substrates were used in this study to create SNiFe@NF catalysts. Experiments demonstrated a positive link between catalytic activity and the KOH concentration in the electrolyte. The addition of sulfur not only increases catalytic activity but also increases resistance to Cl-. This is because sulfur has a low electronegativity, which helps to produce hydroxyl oxides by modulating the electronic structure between Ni and Fe. As predicted, at a current density of 100 mA cm−2, the SNiFe@NF catalyst demonstrated extraordinarily low overpotentials of 90 mV (HER) and 261 mV (OER). Moreover, after undergoing stability tests, the catalyst surface developed a SO42- layer that created a Cl- barrier, providing the basis for excellent stability. Interestingly, the electrolyzer used using SNiFe@NF catalysts also showed an outstanding 1.48 V at 100 mA cm−2 overall water splitting capacity. Furthermore, after 20 hours of continuous operation, no attenuation was seen in the catalysts' performance under high-temperature and high-alkalinity industrial settings. The results of this work provide a simple and efficient method for producing highly active bifunctional corrosion-resistant catalysts, which have significant ramifications for the development of the hydrogen economy.

Efficient conversion of lignin-derived phenols to cycloalkanes over bifunctional catalysts with low loading of ruthenium

Hydrodeoxygenation (HDO) reactions are extensively employed in the conversion of biomass to advanced fuels, which rely heavily on bifunctional catalysts that contain both a metal component and an acidic component. A significant challenge in the development of HDO catalysts is the need to reduce costs while simultaneously enhancing catalytic efficiency. Here, a series of Ru@W/ZrO2 catalysts with an extremely low loading of Ru (0.5 wt%) were successfully synthesized using different Ru or W loading sequences and different Ru/W mass ratios. The catalysts were applied in the HDO reaction of lignin-derived phenols, and their physical and chemical characteristics were revealed by various characterization techniques, including XRD, H2-TPD, NH3-TPD, and XPS. The results suggest that the synthesis method with post-loading Ru leads to improved exposure and utilization of the low-loaded Ru, which effectively serves as the active sites for hydrogenation in catalytic reactions. Under the same reaction conditions, the bifunctional catalyst with post-loading of Ru achieved a complete conversion of phenol into cyclohexane, while the catalyst with simultaneous loading of Ru and W only yielded 42% of cyclohexane. In addition, the Ru/W ratios have also shown significant effects on the HDO performance of the catalyst. The catalyst exhibits the highest hydrogenation activity when the Ru/W ratio is 10, which is further supported by kinetic experiments. This study highlights the significance of the loading sequence of noble metals and the metal/acid ratio in the synthesis of highly active bifunctional catalysts, and also lays the groundwork for the efficient utilization of noble metals in biomass HDO conversion.

Self-supported Pt nanoparticles-NiFeP nanosheets arrays nanohybrid with hydrophilic surface towards urea electrolysis

Urea-assisted water electrolysis is a clean, sustainable, and energy-saving method towards hydrogen production. However, the development of earth-abundant, stable, and highly active bifunctional catalysts towards urea electrolysis is still a significant technical challenge. Herein, the highly dispersed Pt nanoparticles decorated NiFeP nanosheets arrays on nickel foam (Pt-NiFeP/NF) electrode is rationally designed, which combines the advantages of superhydrophilic interface, ultrathin nanostructure and open three-dimensional (3D) architecture. Consequently, Pt-NiFeP/NF displays a remarkable electroactivity towards both hydrogen evolution reaction (HER) and urea electrooxidation reaction (UEOR), which only needs the overpotential of 32 mV to achieve the current density of 10 mA cm−2 towards HER, and drives a current density of 50 mA cm−2 at 1.38 V towards UEOR. More importantly, the urea electrolysis system assembled with Pt-NiFeP/NF only requires a cell voltage of 1.41 V to achieve a current density of 100 mA cm−2, much lower than the traditional water electrolysis (1.94 V). This work promotes the application of Pt nanoparticles decorated bimetallic phosphides as a bifunctional catalyst towards urea-rich wastewater treatment and green electrochemical hydrogen production.

Scalable exothermic synthesis of sprout-like Ni-Co-Fe trimetallic oxide nanoparticles anchored on N-doped carbon nanotubes as bifunctional oxygen catalysts for zinc-air batteries

Zn-air batteries (ZABs) offer a high specific energy density, cost-effectiveness, and eco-friendliness. Hence, they are attractive candidates for use as sustainable energy-storage devices. However, their practical applications are limited by their high bifunctional oxygen evolution reaction/oxygen reduction reaction (OER/ORR) overpotential and sluggish kinetics. To address these limitations, in this study, a highly active bifunctional oxygen catalyst, TNPs@N-CNT, is developed, in which Ni-Co-Fe trimetallic nanoparticles are anchored on N-doped carbon networks. TNPs@N-CNT is synthesized via the thermally driven combustion of collodion fuel. The carbonization of melamine foam containing pyridinic N in TNPs@N-CNT enhances the ORR and affords a high catalytic surface area and high electrical conductivity. Morphological studies and chemical characterization aid in finely tuning the thermal processing conditions, affording a TNPs@N-CNT suitable for charge transfer. TNPs@N-CNT shows enhanced ORR activity (half-wave potential = 0.62 V and onset potential = 1.49 V) in alkaline media. A ZAB with TNPs@N-CNT as the air cathode exhibits an output power density of 90 mW cm−2 and excellent cycling stability for over 200 h, outperforming previously reported carbon-supported precious-metal catalysts. This tunable and scalable fabrication strategy could promote the development of novel mesoporous structures combined with high-efficiency multi-metallic catalysts for applications in energy-storage systems.

Interfacial engineering of hierarchical MoNi4/NiO heterostructure nanosheet arrays as bifunctional electrocatalysts for urea-assisted energy-saving hydrogen production

Employing urea oxidation reaction (UOR) to substitute slow oxygen evolution reaction (OER) is an effective technique to accomplish high-efficiency hydrogen production. The exploitation of inexpensive and highly active bifunctional catalyst still remains a considerable challenge. We report the hybrid nanosheet arrays constructed of MoNi4/NiO heterojunction with hierarchically crosslinked network architecture by hydrothermal reaction and subsequent annealing process under H2/Ar atmosphere. The special heterostructure with neoteric morphology can promote electron shift and interface interaction through the powerful coupling interface between MoNi4 and NiO, increasing charge transfer speed, intrinsic activity and electrolyte transport. Only 31 mV overpotential and 1.37 V potential are needed to arrive 10 mA cm−2 for hydrogen evolution reaction (HER) and UOR, respectively. For the two-electrode urea-assisted electrolyzer, the lower potential of 1.41 V is required to reach 10 mA cm−2. Moreover, it displays superior stability with unceasing working for 54 h at the cell voltage of 1.41 V without obvious activity degeneration. This research provides an insight on the construct of high-efficiently bifunctional catalyst by synergistic coupling of NiMo-based alloys with metal oxides.

A novel supported Mn-Ce catalyst with meso-microporous structure for low temperature synergistic removal of nitrogen oxides and toluene: structure–activity relationship and synergistic mechanism

The design and preparation of highly stable and active bifunctional catalysts that function well over a wide temperature range and resist poisoning is a major obstacle in the dual objective of eliminating nitrogen oxides and toluene from flue gas. In this reported work, a series of supported Mn-Ce catalysts with different molecular sieves support (microporous MnCe/ZSM-5, mesoporous MnCe/AlMCM-41 and micro-mesoporous MnCe/ZSM-5@AlMCM-41) were developed and their reaction performance was evaluated for the process of simultaneously removal of NOx and toluene. Of the catalysts prepared, the MnCe/ZSM-5@AlMCM-41 catalyst appeared to exhibit excellent catalytic activity and good poisoning resistance. The catalysts’ structure–activity relationships were studied using a series of characterizations. These characterization test results revealed that the outstanding catalytic activity and poisoning resistance of the MnCe/ZSM-5@AlMCM-41 catalyst were associated with its suitable micro-mesopore proportion, high ratio of Mn4+, Ce3+ and the abundance of various active oxygen groups on the catalyst surface. Further investigation revealed the details of the synergistic mechanism of the catalysts that were responsible for catalytic removal of NOx and toluene. The results of this work showed that 1) appropriate proportions of mesopores in the catalysts mitigated the reaction of toluene or oxidation intermediates with NH3 and NO to form nitrogen-containing intermediate species (benzonitrile and benzamide). This reduced the population of these N-containing intermediate species present at the catalyst’s active sites; 2) appropriate proportions of mesopores in the catalysts helped to reduce the reaction between the nitrite/nitrate groups with toluene, thus promoting the utilization of activated nitrate/nitrite species in the NH3-SCR reaction.

Amine-rich Nickel(II)-Xerogel as a Highly Active Bifunctional Metallo-organo Catalyst for Aqueous Knoevenagel Condensation and Solvent-free CO2 Cycloaddition.

Metallogels formed from supramolecular interactions of low-molecular-weight gelators (LMWGs) combine the qualities of heterogeneous catalysts and offer the advantages of multifunctionality owing to the facile installation of desired task-specific moieties on the surface and along the channels of the gels. We discuss the applications of a triazole-based Ni(II) gel-derived xerogel (NiXero) having a high density of Ni(II)-nodes and appended primary amines as a recyclable heterogeneous catalyst for Knoevenagel condensation of aldehyde and malononitrile in water and the solvent-free cycloaddition of CO2 to form a series of cyclic carbonates with near-quantitative conversion of the respective epoxides, with low catalyst loading (0.59 mol %), high catalyst stability, and recyclability. The structural advantages of NiXero, due to the concurrent presence of bifunctional Lewis acid-base sites on the channels, open Ni(II) nodes, Ntriazole, pendant -NH2 and its chemical stability, are conducive to the cooperative heterogeneous catalytic activity under mild conditions. This work emphasizes the effective amalgamation of metals with purpose-built ligand systems for the construction of metallogels and their utility as heterogeneous catalysts for desired organic transformations.

Design of ZIF-67-derived Fe, N and F co-doped porous carbon material and evaluation of its ORR and OER performance

Addressing the low conductivity and porosity of ZIF-67-based oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts is a top priority. Noble metal-free highly active bifunctional catalysts F-N/FeCoNC900 with three-dimensional interconnected porous structure and high electrical conductivity were successfully prepared by co-doping Fe, F, and N on the precursor ZIF-67. In terms of ORR performance, F-N/FeCoNC900 has a high onset potential (Eonset) of 0.97 V (vs. RHE), a half-wave potential (E1/2) of 0.87 V (vs. RHE), and an ultimate current density (JL) of 5.7 mA cm−2, superior to commercially available Pt/C (0.95 V, 0.85 V, 5.3 mA cm−2). In addition, F-N/FeCoNC900 provides high ORR activity with constant 4 electron transfer (n = 3.91–3.99) for methanol resistance and long-lasting stability (initial current retention of 96.32% after 21600 s). In terms of OER performance, F-N/FeCoNC900 exhibits ultra-low overpotential (273 mV) and ultra-high Faraday efficiency (93%) at constant 4 (n = 3.91–3.99) electron transfer mode. This work provides a new pathway of doped ZIFs-derived composites as efficient bifunctional non-precious metal catalysts.

CoSe2 nanoparticles anchored on CoNC carbon nanoplates as bifunctional electrocatalyst for flexible rechargeable Zn-air batteries

A flexible solid rechargeable Zn-air battery for advanced energy conversion and storage has extensive applications in portable electric sources, wildlife rescue and flexible wearable systems. Herein, the CoSe2 nanoparticles anchored on cobalt-embedded N-doping carbon nanoplates (CoSe2/CoNC) is developed as a highly active bifunctional catalyst via pyrolysis and selenization of bimetallic zeolitic imidazolate frameworks containing Zn and Co. The introduction of inactive Zn generates strong electrochemically active surface areas due to the synergistic effect between CoSe2 nanoparticles and CoNC matrix. Further, CoSe2/CoNC exhibits prominent Zn–air battery performance and even outperforms the commercially available noble-metal catalysts. Notably, a high-rate flexible Zn-air battery enabled by an alkaline composite polyacrylic acid-carboxymethyl cellulose electrolyte delivers the open-circuit potential of 1.51 V. The battery offers high wearability and performs very well under various conditions, such as soaking, drilling and sewing.

Rational design of 2D MBene-based bifunctional OER/ORR dual-metal atom catalysts: a DFT study.

Designing highly active, low-cost, and bifunctional oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) catalysts is urgent for the development of metal-air batteries. Herein, by density functional theory (DFT) calculations, we systematically reported a series of dual-metal atom adsorbed novel two-dimensional (2D) MBenes as efficient bifunctional catalysts for the OER/ORR (namely 2TM/TM1TM2-Mo2B2O2, TM = Mn, Fe, Co, Ni). Our theoretical results show that 2Ni-Mo2B2O2, FeCo-Mo2B2O2 and CoNi-Mo2B2O2 exhibit outstanding OER/ORR catalytic activity with overpotentials of 0.49/0.27 V, 0.38/0.50 V and 0.25/0.51 V, respectively, exceeding those of IrO2(110) for the OER and Pt(111) for the ORR. Additionally, these highly active bifunctional catalysts can effectively suppress the hydrogen evolution reaction (HER), ensuring the absolute preference for the OER/ORR. More importantly, the Bader charge (QTM) of adsorbed dual-metal atoms is used as a descriptor of OER/ORR catalytic activity, which is linearly related to ηORR and volcanically related to -ηOER. Our work not only provides new theoretical guidance for developing noble metal-free bifunctional electrocatalysts but also enriches the application of MBenes in electrocatalysis.

A novel, efficient and magnetically recyclable Cu-Ni bimetallic alloy nanoparticle as a highly active bifunctional catalyst for Pd-free Sonogashira and C-N cross-coupling reactions: a combined theoretical and experimental study.

In this study, a Fe3O4@SiO2@Cyt-Ni/Cu nanocomposite as a novel heterogeneous bimetallic catalyst was synthesized which exhibits efficient performance for the Sonogashira and C-N cross-coupling reactions. The characterization of the catalyst was studied by FT-IR, PXRD, VSM, EDX, TEM, FE-SEM and TGA analyses. The geometry optimization and relative energies of the designed bimetallic complexes were theoretically determined using density functional theory (DFT) calculation at the B3LYP/6-31G**/LANL2DZ level. The catalyst showed good activity in the coupling of various aryl halides with alkynes (Sonogashira reaction) as well as aryl halide with N-heterocycles and achieved coupling products with good to high yields for all of them in a short time. The high catalytic performance could be due to the synergistic effect between Ni and Cu, which causes the reaction to proceed more efficiently. This heterogeneous nanocatalyst could be easily recovered from the reaction mixture with an external magnet and reused for 7 consecutive runs with minimal loss of catalytic activity.

Anion-modulated CoPelectrode asbifunctional electrocatalystfor anion-exchange membrane hydrazine-assisted water electrolyser.

The hydrazine oxidation reaction (HzOR) is considered as a promising alternative process of the oxygen evolution reaction (OER) to realize more energy-efficient hydrogen generation. However, the lack of highly active bifunctional catalysts poses a huge challenge to this strategy. In this work, we report a novel and universal electrodeposition strategy to rationally synthesize a self-supporting electrode. The utilization of ammonium fluoride helps to modulate not only the morphology of CoP, but also the synchronous formation of an anion-modified structure, leading to an excellent bifunctional performance. The optimal F-CoP/CF exhibits small potentials of -90 mV and 41 mV at 1 A cm-2, high stability and low Tafel slopes of 28 mV dec-1 and 3.26 mV dec-1 for the HER and HzOR, respectively. The highly efficient and stable bifunctional activity of F-CoP/CF can be further confirmed in an anion-exchange membrane hydrazine-assisted water electrolyzer (0.49 V at 1 A cm-2). Utilizing the density functional theory calculations, the optimized adsorption energy of water molecules and hydrogen intermediates of the HER as well as the rate-determining step of the HzOR are demonstrated for the F-CoP.

Phosphorus-induced activation of Ir metallene for efficient acidic overall water electrolysis.

In this work, we synthesize P-doped Ir metallene (P-Ir metallene) with rich defects as a highly active bifunctional catalyst towards the hydrogen evolution reaction and oxygen evolution reaction, requiring overpotentials of 28 and 279 mV to drive 10 mA cm-2 in 0.5 M H2SO4, respectively. Moreover, P-Ir metallene exhibits excellent electrocatalytic performance for overall water splitting, producing hydrogen at 10 mA cm-2 with a low operation voltage of 1.508 V. This study proposes the incorporation of phosphorus into noble metals to improve the electrocatalytic performance for water splitting.

Facile one pot synthesis of nitrogen doped reduced graphene oxide supported Co3O4 nanoparticles as bifunctional catalysts for the reduction of 4-nitrophenol and NaBH4 hydrolysis

The development of catalyst materials with significant potential and multifunctional applicability is essential for sustainable energy and environmental applications. The present work reports the preparation of nitrogen doped reduced graphene oxide supported Co3O4 nanoparticles (NGCO) via a simple and cost effective one pot synthesis method, at a relatively low temperature. The prepared NGCO composites were employed for the first time as active bifunctional catalysts in the reduction of 4-nitrophenol (4NP) and NaBH4 hydrolysis. The NGCO catalyst exhibited excellent catalytic activity and stability for the 4NP conversion with a mass normalized rate constant of 97.8 min−1g−1 at 303 K. The concentration (0.7 mM) and volume (20 mL) of the 4NP solution used in this study was higher than most of the works in the literature and that signifies the novelty of the prepared NGCO catalyst materials. The NGCO catalysts also showed potential activity and durability in liberating hydrogen from NaBH4, via hydrolysis, with a maximum specific hydrogen generation rate of 2090.6 mL min−1 gCo−1. The kinetics of the catalytic NaBH4 hydrolysis reaction was investigated using zero order and first order kinetic models. The experimental data was well-described with the zero-order kinetic model. The improved catalytic activity of the NGCO composites relative to the unsupported Co3O4 nanoparticles is due to the excellent dispersibility of the active sites and the synergetic action of both Co3O4 and N doped graphene support in NGCO.

Self‐supporting Nickel Phosphide/ Hydroxides Hybrid Nanosheet Array as Superior Bifunctional Electrode for Urea‐Assisted Hydrogen Production

AbstractUrea oxidation reaction (UOR) is an important strategy to synergistically realize energy‐saving hydrogen evolution reaction (HER) and urea‐rich wastewater purification by replacing water oxidation in water electrolysis. However, the efficient realization of integral urea electrolysis remains challenging. Herein, a self‐supporting Ni2P−Ni(OH)2 hybrid nanosheet array on nickel foam (Ni2P@Ni(OH)2/NF) is designed by a simple hydrothermal accompanied by electrodeposition strategy, representing a new class of bifunctional electrodes for urea‐assisted water electrolysis. The Ni2P@Ni(OH)2/NF reaches the current density of 100 mA cm−2 at potentials of −0.16 V and 1.388 V, along with small Tafel slopes of 69 mV dec−1 and 33 mV dec−1 for HER/UOR, respectively. For the HER||UOR coupled system, the constructed electrolyzer only needs 1.38 V to realize the current density of 100 mA cm−2 under 80 °C. The superior bifunctional activity of the Ni2P@Ni(OH)2/NF electrode is ascribed to the combined merits of the Ni2P@Ni(OH)2 heterostructure, enriching the catalytic active sites and offering a faster charge transfer process for electrolysis. Our work provides important insights into the design of highly active bifunctional catalysts from the perspective of overall water electrolysis.

Tailored Crafting of CoP/Ni2P Nanoparticles Coupled with N-Doped Nanoporous Carbon to Enable Efficient Hydrogen and Oxygen Evolution

Rationally tailoring a nonprecious metal and highly active bifunctional catalyst with desirable nanoarchitecture and composition for water electrolysis is of key value for sustainable and clean energy production. Herein, we designed nanoporous N-doped carbon (NC) as a support for dispersion and anchoring of bimetallic phosphide nanoparticles (CoP/Ni2P). Thanks to the uniformly anchored nanosized CoP/Ni2P nanoparticles offering rich active sites and the coupling effect between these nanoparticles and a nanoporous NC support to ensure promising conductivity and structural stability, the as-prepared hybrid (CoP(Ni2P)/NC) exhibits prominent electrocatalytic performances toward hydrogen evolution (or oxygen evolution) in alkaline electrolytes, in terms of a small overpotential of 216 mV (or 338 mV) at 10 mA cm–2 and a low Tafel slope of 84 mV dec–1 (or 60 mV dec–1), as well as exceptional long-term stability.

Synergistically tuning the graphitic degree, porosity, and the configuration of active sites for highly active bifunctional catalysts and Zn-air batteries

Synergistically tuning the graphitic degree, porosity, and the configuration of active sites for highly active bifunctional catalysts and Zn-air batteries

Pd2Ga nanorods as highly active bifunctional catalysts for electrosynthesis of acetic acid coupled with hydrogen production

The production of hydrogen from water splitting is hampered by the sluggish oxygen evolution reaction (OER). To overcome the OER limitation, herein we propose the electrosynthesis of value-added acetic acid from ethanol as the anodic reaction using high activity catalyts. For this strategy to be cost-effective, we develop a bifunctional catalyst based on Pd2Ga nanorods. Such Pd2Ga/C-based catalyst presents outstanding activity, selectivity and also stability for the electrocatalytic ethanol-to-acetic acid conversion with a current density above 164 mA cm−2 and a mass activity of 1.97 A mg−1Pd. Besides, its activity for hydrogen production is comparable to that of commercial Pt/C catalysts. Using Pd2Ga/C as a bifunctional catalyst for both water reduction at the cathode and ethanol oxidation at the anode, these two coupled reactions are demonstrated to be an energy-efficient approach for the simultaneous production of high purity acetic acid and hydrogen. The assembled electrolyzer requires a small voltage input of 0.62 V to reach a current density of 10 mA cm−2, much lower than that of cells based on commercial Pt/C or Pd/C catalyst. Density functional theory calculations reveal that the high performance of the coupled system relies on a combination of an electronic and bifunctional effect of Ga, reducing the hydrogen-binding energy on the Pd site and at the same time actively participating in the reaction by providing OH− binding sites and reducing the energy barrier of the ethanol oxidation rate-determining step.