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Atomically precise supported nanocluster catalysts (APSNCs), which feature exact atomic composition, well‐defined structures, and unique catalytic properties, offer an exceptional platform for understanding the structure‐performance relationship at the atomic level. However, fabricating APSNCs with precisely controlled and uniform metal atom numbers, as well as maintaining a stable structure, remains a significant challenge due to uncontrollable dispersion and easy aggregation during synthetic and catalytic processes. Herein, we developed an effective ligand engineering strategy to construct a Pt6 nanocluster catalyst stabilized on oxidized carbon nanotubes (Pt6/OCNT). The structural analysis revealed that Pt6 nanoclusters in Pt6/OCNT were fully exposed and exhibited a planar structure. Furthermore, the obtained Pt6/OCNT exhibited outstanding acidic HOR performances with a high mass activity of 18.37 A ⋅ mgpt−1 along with excellent stability during a 24 h constant operation and good CO tolerance, surpassing those of the commercial Pt/C. Density functional theory (DFT) calculations demonstrated that the unique geometric and electronic structures of Pt6 nanoclusters on OCNT altered the hydrogen adsorption energies on catalytic sites and thus lowered the HOR theoretical overpotential. This work presents a new prospect for designing and synthesizing advanced APSNCs for efficient energy electrocatalysis. [ABSTRACT FROM AUTHOR]

Cu‐catalyzed electrochemical CO2 reduction reaction (CO2RR) produces multi‐carbon (C2+) chemicals with considerable selectivities and activities, yet required high overpotentials impede its practical application. Here, we design interfaces with abrupt coordination number (CN) changes that greatly reduce the applied potential for achieving high C2+ Faradaic efficiency (FE). Encouraged by the mechanistic finding that the coupling between *CO and *CO(H) is the most probable C−C bond formation path, we use Cu2O‐ and Cu‐phthalocyanine‐derived Cu (OD−Cu and PD−Cu) to build the interface. Using operando X‐ray absorption spectroscopy (XAS), we find that the Cu CN of OD−Cu is ~11, favoring CO* adsorption, while the PD−Cu has a COH*‐favorable CN of ~4. Operando Raman spectroscopy revealed that the interfaces with abrupt CN changes promote *OCCOH formation. As a result, the designed catalyst achieves a C2+ FE of 85±2 % at 220 mA cm−2 in a zero‐gap CO2 electrolyzer. An improvement of C2+ FE by 3 times is confirmed at the low potential regime where the current density is 60–140 mA cm−2, compared to bare OD−Cu. We report a 45‐h stable CO2RR operation at 220 mA cm−2, producing a C2+ product FE of ~80 %. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) is considered a promising candidate catalyst for alkaline hydroxide oxidation reaction (HOR) due to its hydrogen binding energy (HBE) like that of platinum (Pt) and its much higher oxygenophilicity than that of Pt. However, Ru still suffers from insufficient intrinsic activity and CO resistance, which hinders its widespread use in anion exchange membrane fuel cells (AEMFCs). Here, we report a hybrid catalyst (RuCo)NC+SAs/N‐CNT consisting of dilute RuCo alloy nanoparticles and atomically single Ru and Co atoms on N‐doped carbon nanotubes The catalyst exhibits a state‐of‐the‐art activity with a high mass activity of 7.35 A mgRu−1. More importantly, when (RuCo)NC+SAs/N‐CNT is used as an anode catalyst for AEMFCs, its peak power density reaches 1.98 W cm−2, which is one of the best AEMFCs properties of noble metal‐based catalysts at present. Moreover, (RuCo)NC+SAs/N‐CNT has superior long‐time stability and CO resistance. The experimental and density functional theory (DFT) results demonstrate that the dilute alloying and monodecentralization of the exotic element Co greatly modulates the electronic structure of the host element Ru, thus optimizing the adsorption of H and OH and promoting the oxidation of CO on the catalyst surface, and then stimulates alkaline HOR activity and CO tolerance of the catalyst. [ABSTRACT FROM AUTHOR]

Revealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO2 into ethylene (C2H4), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low‐coordination copper‐based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm−2. Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full‐cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO2RR) catalysts but also advances CO2 electrolysis technologies for industrial application. [ABSTRACT FROM AUTHOR]

Developing a high‐efficiency, stable, and CO‐toxicant‐resistant low‐cost hydrogen oxidation reaction (HOR) electrocatalyst is challenging but is vital for practical proton/anion exchange membrane fuel cells. Herein, an efficient pH‐universal HOR catalyst Pt1@Co1CN is fabricated, in which the electronic structure of single Pt sites is modulated by isolated Co atoms pre‐anchored on nitrogen‐doped carbon. Pt1@Co1CN exhibits superior HOR activity and durability under pH‐universal media than Pt1@CN (anchored single Pt atoms on nitrogen‐doped carbon) and commercial PtRu/C and Pt/C. More importantly, Pt1@Co1CN possesses much better CO anti‐poisoning ability than Pt1@CN and commercial PtRu/C and Pt/C. It is speculated that the superior pH‐universal HOR performance can be attributed to the inter‐regulation of adjacent Co and Pt sites, leading to the downshift of anti‐bonding state and consequently strengthening the *H adsorption, which promotes the kinetics of HOR. [ABSTRACT FROM AUTHOR]

Advancing the performance of the Cu‐catalyzed electrochemical CO2 reduction reaction (CO2RR) is crucial for its practical applications. Still, the wettable pristine Cu surface often suffers from low exposure to CO2, reducing the Faradaic efficiencies (FEs) and current densities for multi‐carbon (C2+) products. Recent studies have proposed that increasing surface availability for CO2 by cation‐exchange ionomers can enhance the C2+ product formation rates. However, due to the rapid formation and consumption of *CO, such promotion in reaction kinetics can shorten the residence of *CO whose adsorption determines C2+ selectivity, and thus the resulting C2+ FEs remain low. Herein, we discover that the electro‐kinetic retardation caused by the strong hydrophobicity of quaternary ammonium group‐functionalized polynorbornene ionomers can greatly prolong the *CO residence on Cu. This unconventional electro‐kinetic effect is demonstrated by the increased Tafel slopes and the decreased sensitivity of *CO coverage change to potentials. As a result, the strongly hydrophobic Cu electrodes exhibit C2+ Faradaic efficiencies of ≈90 % at a partial current density of 223 mA cm−2, more than twice of bare or hydrophilic Cu surfaces. [ABSTRACT FROM AUTHOR]

Exploring efficient strategies to achieve novel high‐efficiency catalysts for water splitting is of great significance to develop hydrogen energy technology. Herein, unique molybdenum (Mo)‐doped ruthenium–cobalt oxide (Mo–RuCoOx) nanosheet arrays are prepared as a high‐performance bifunctional electrocatalyst toward hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) through combining electronic and vacancy engineering. Theoretical calculations and experimental results reveal that the incorporation of Ru and Mo can effectively tune the electronic structure, and the controllable Mo dissolution coupling with the oxygen vacancy generation during surface reconstruction is able to optimize the adsorption energy of hydrogen/oxygen intermediates, thus greatly accelerating the kinetics for both HER and OER. As a result, the Mo–RuCoOx nanoarrays exhibit remarkably low overpotentials of 41 and 156 mV at 10 mA cm−2 for HER and OER in 1 m KOH, respectively. Furthermore, the two‐electrode electrolyzer assembled by the Mo–RuCoOx nanoarrays requires a cell voltage as low as 1.457 V to achieve 10 mA cm−2 for alkaline overall water splitting. This work holds great promise to develop novel and highly active electrocatalysts for future energy conversion applications. [ABSTRACT FROM AUTHOR]

Bismuth‐based materials have been recognized as promising catalysts for the electrocatalytic CO2 reduction reaction (ECO2RR). However, they show poor selectivity due to competing hydrogen evolution reaction (HER). In this study, we have developed an edge defect modulation strategy for Bi by coordinating the edge defects of bismuth (Bi) with sulfur, to promote ECO2RR selectivity and inhibit the competing HER. The prepared catalysts demonstrate excellent product selectivity, with a high HCOO− Faraday efficiency of ≈95 % and an HCOO− partial current of ≈250 mA cm−2 under alkaline electrolytes. Density function theory calculations reveal that sulfur tends to bind to the Bi edge defects, reducing the coordination‐unsaturated Bi sites (*H adsorption sites), and regulating the charge states of neighboring Bi sites to improve *OCHO adsorption. This work deepens our understanding of ECO2RR mechanism on bismuth‐based catalysts, guiding for the design of advanced ECO2RR catalysts. [ABSTRACT FROM AUTHOR]

The epitaxial heterostructure can be rationally designed based on the in situ growth of two compatible phases with lattice similarity, in which the modulated electronic states and tuned adsorption behaviors are conducive to the enhancement of electrocatalytic activity. Herein, theoretical simulations first disclose the charge transfer trend and reinforced inherent electron conduction around the epitaxial heterointerface between Ru clusters and Ni3N substrate (cRu‐Ni3N), thus leading to the optimized adsorption behaviors and reduced activation energy barriers. Subsequently, the defect‐rich nanosheets with the epitaxially grown cRu‐Ni3N heterointerface are successfully constructed. Impressively, by virtue of the superiority of intrinsic activity and reaction kinetics, such unique epitaxial heterostructure exhibits remarkable bifunctional catalytic activity toward electrocatalytic OER (226 mV @ 20 mA cm−2) and HER (32 mV @ 10 mA cm−2) in alkaline media. Furthermore, it also shows great application prospect in alkaline freshwater and seawater splitting, as well as solar‐to‐hydrogen integrated system. This work could provide beneficial enlightenment for the establishment of advanced electrocatalysts with epitaxial heterointerfaces. [ABSTRACT FROM AUTHOR]

Theoretical calculations unveil that the formation of Os‐OsSe2 heterostructures with neutralized work function (WF) perfectly balances the electronic state between strong (Os) and weak (OsSe2) adsorbents and bidirectionally optimizes the hydrogen evolution reaction (HER) activity of Os sites, significantly reducing thermodynamic energy barrier and accelerating kinetics process. Then, heterostructural Os‐OsSe2 is constructed for the first time by a molten salt method and confirmed by in‐depth structural characterization. Impressively, due to highly active sites endowed by the charge balance effect, Os‐OsSe2 exhibits ultra‐low overpotentials for HER in both acidic (26 mV @ 10 mA cm−2) and alkaline (23 mV @ 10 mA cm−2) media, surpassing commercial Pt catalysts. Moreover, the solar‐to‐hydrogen device assembled with Os‐OsSe2 further highlights its potential application prospects. Profoundly, this special heterostructure provides a new model for rational selection of heterocomponents. [ABSTRACT FROM AUTHOR]

Electrochemical 2‐electron oxygen reduction reaction (ORR) is a promising route for renewable and on‐site H2O2 production. Oxygen‐rich carbon nanotubes have been demonstrated their high selectivity (≈80%), yet tailoring the composition and structure of carbon nanotubes to further enhance the selectivity and widen working voltage range remains a challenge. Herein, combining formamide condensation coating and mild temperature calcination, a nitrogen and oxygen comodified carbon nanotubes (N,O‐CNTs) electrocatalyst is synthesized, which shows excellent selective (>95%) H2O2 selectivity in a wide voltage range (from 0 to 0.65 V versus reversible hydrogen electrode). It is significantly superior to the corresponding selectivity values of CNTs (≈50% in 0–0.65 V vs RHE) and O‐CNTs (≈80% in 0.3–0.65 V vs RHE). Density functional theory calculations revealed that the C neighbouring to N is the active site. Introducing O‐related species can strengthen the adsorption of intermediates *OOH, while N‐doping can weaken the adsorption of in situ generated *O and optimize the *OOH adsorption energy, thus improving the 2‐electron pathway. With optimized N,O‐CNTs catalysts, a Janus electrode is designed by adjusting the asymmetric wettability to achieve H2O2 productivity of 264.8 mol kgcat–1 h–1. [ABSTRACT FROM AUTHOR]

Electrochemical 2‐electron oxygen reduction reaction (ORR) is a promising route for renewable and on‐site H2O2 production. Oxygen‐rich carbon nanotubes have been demonstrated their high selectivity (≈80%), yet tailoring the composition and structure of carbon nanotubes to further enhance the selectivity and widen working voltage range remains a challenge. Herein, combining formamide condensation coating and mild temperature calcination, a nitrogen and oxygen comodified carbon nanotubes (N,O‐CNTs) electrocatalyst is synthesized, which shows excellent selective (>95%) H2O2 selectivity in a wide voltage range (from 0 to 0.65 V versus reversible hydrogen electrode). It is significantly superior to the corresponding selectivity values of CNTs (≈50% in 0–0.65 V vs RHE) and O‐CNTs (≈80% in 0.3–0.65 V vs RHE). Density functional theory calculations revealed that the C neighbouring to N is the active site. Introducing O‐related species can strengthen the adsorption of intermediates *OOH, while N‐doping can weaken the adsorption of in situ generated *O and optimize the *OOH adsorption energy, thus improving the 2‐electron pathway. With optimized N,O‐CNTs catalysts, a Janus electrode is designed by adjusting the asymmetric wettability to achieve H2O2 productivity of 264.8 mol kgcat–1 h–1. [ABSTRACT FROM AUTHOR]

Designing synergistic heterogeneous catalytic interfaces is the key to developing highly compatible pH‐universal electrocatalysts for complex chemical environments. Our theoretical calculation results demonstrate that the Ru‐Ru2P heterointerface can not only promote the redistribution of charges, but also reduce the d‐band center, and then enhances the adsorption capacity of the key intermediate. However, in situ and facile synthesis of Ru‐Ru2P heterostructures is severely limited by thermodynamic obstacles. Herein, we propose a molten salt‐assisted catalytic synthesis scheme, and successfully build a series of homologous metallic Ru‐Ru2P heterostructure catalysts with different molar ratios of Ru to P under atmospheric pressure and low‐temperature (400°C). The resultant Ru‐Ru2P with rich heterostructures show the Pt‐like HER performance in different pH media. Particularly, it is prominent under alkaline conditions (18 mV @ 10 mA cm−2), which outperforms the Pt catalyst (37 mV @ 10 mA cm−2). Furthermore, Ru‐Ru2P heterostructures also show certain potential in the electrolysis of seawater to produce hydrogen. This work represents a significant supplement of high‐efficiency pH‐universal HER catalysts, and provides a new light on interface engineering in energy technology fields and beyond. [ABSTRACT FROM AUTHOR]

High‐performance transition metal chalcogenides (TMCs) as electrocatalysts for two‐electron oxygen reduction reaction (2e‐ORR) in alkaline medium are promising for hydrogen peroxide (H2O2) production, but their synthesis remains challenging. In this work, a titanium‐doped zinc–cobalt sulfide hollow superstructure (Ti–ZnCoS HSS) is rationally designed as an efficient electrocatalyst for H2O2 electrosynthesis. Synthesized by using hybrid metal–organic frameworks (MOFs) as precursors after sulfidation treatment, the resultant Ti–ZnCoS HSS exhibits a hollow‐on‐hollow superstructure with small nanocages assembled around a large cake‐like cavity. Both experimental and simulation results demonstrate that the polymetallic composition tailors the d‐band center and binding energy with oxygen species. Moreover, the hollow superstructure provides abundant active sites and promotes mass and electron transfer. The synergistic d‐band center and superstructure engineering at both atomic and nanoscale levels lead to the remarkable 2e‐ORR performance of Ti–ZnCoS HSS with a high selectivity of 98%, activity (potential at 1 mA cm−2 of 0.774 V vs reversible hydrogen electrode (RHE)), a H2O2 production rate of 675 mmol h–1 gcat–1, and long‐term stability in alkaline condition, among the best 2e‐ORR electrocatalysts reported to date. This strategy paves the way toward the rational design of polymetallic TMCs as advanced 2e‐ORR catalysts. [ABSTRACT FROM AUTHOR]

It is a considerably promising strategy to produce fuels and high‐value chemicals through an electrochemical conversion process in the green and sustainable energy systems. Catalysts for electrocatalytic reactions, including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), nitrogen reduction reaction (NRR), carbon dioxide reduction reaction (CO2RR), play a significant role in the advanced energy conversion technologies, such as water splitting devices, fuel cells, and rechargeable metal‐air batteries. Developing low‐cost and highly efficient electrocatalysts is closely related to establishing the composition–structure–activity relationships and fundamental understanding of catalytic mechanisms. Density functional theory (DFT) is emerging as an important computational tool that can provide insights into the relationship between the electrochemical performances and physical/chemical properties of catalysts. This article presents a review on the progress of the DFT, and the computational simulations, within the framework of DFT, for the electrocatalytic processes, as well as the computational designs and virtual screenings of new electrocatalysts. Some useful descriptors and analysis tools for evaluating the electrocatalytic performances are highlighted, including formation energies, d‐band model, scaling relation, eg orbital occupation, and free energies of adsorption. Furthermore, the remaining questions and perspectives for the development of DFT for electrocatalysis are also proposed. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs), where individual metal atoms are anchored on support, hold great promise for electrocatalytic hydrogen evolution reactions (HERs). The inherent simplicity of the single‐atom center restricts opportunities for further enhancement. Binuclear SACs, incorporating two different metal sites, can further improve HER kinetics. However, the underlying mechanisms of the HER at the binuclear sites are complex and not fully understood, hampering the design of new efficient catalyst structures. Here, a comprehensive investigation is presented into phosphorus‐doped iron and cobalt bimetallic SACs supported on nitrogen‐doped graphitic carbon (P/FeCo‐NC), focusing on the potential mechanisms underpinning their enhanced HER activity. P/FeCo‐NC exhibits overpotentials of 38 and 95 mV at 10 mA cm2 in 0.5 m H2SO4 and 1 m KOH, respectively, nearing the acidic performance of commercial Pt/C (33 mV). Theoretical studies reveal that the phosphorus bridge significantly alters the electronic properties of the Fe active sites, while the adjacent Co atoms modulate the electronic environment, further optimizing the hydrogen adsorption‐free energy toward more favorable kinetics. This work highlights the structure‐activity relationships of bimetallic SACs and opens perspectives for future applications. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) production by electrochemical two‐electron water oxidation reaction (2e‐WOR) is a promising approach, where high‐performance electrocatalysts play critical roles. Here, the synthesis of nanostructured CaSnO3 confined in conductive carbon fiber membrane with abundant oxygen vacancy (OV) as a new generation of 2e‐WOR electrocatalyst is reported. The CaSnO3@carbon fiber membrane can be directly used as a self‐standing electrode, exhibiting a record‐high H2O2 production rate of 39.8 µmol cm−2 min−1 and a selectivity of ≈90% (at 2.9 V vs reversible hydrogen electrode). The CaSnO3@carbon fiber membrane design improves not only the electrical conductivity and stability of catalysts but also the inherent activity of CaSnO3. Density functional theory calculation further indicates the crucial role of OV in increasing the adsorption free energy toward oxygen intermediates associated with the competitive four‐electron water oxidation reaction pathway, thus enhancing the activity and selectivity of 2e‐WOR. The findings pave a new avenue to the rational design of electrocatalysts for H2O2 production from water. [ABSTRACT FROM AUTHOR]

Improving the catalytic performance of graphene for the electrochemical CO2 reduction reaction (CO2RR) has been a promising avenue to abate the concentration of greenhouse gas and develop a strategy of CO2 recyclable utilization. In this paper, we systematically investigate the catalytic performance of different active sites, both on the undoped and N‐doped graphene sheets, under non‐strained (0%) and 1%, 5% and 10% lattice strain (LS) via density functional theory calculations. The results uncover that N‐doping and LS synergistically modulate the electronic structures of graphene, enhancing the electrocatalytic reduction of CO2 to CO. Among all models in this work, the site with the highest catalytic activity toward CO2RR is shown to be the carbon atom at the ortho‐position (labeled as G2) relative to the nitrogen heteroatom (denoted by N1) on the graphene under 10% LS due to its lowest overpotential of 1.19 eV. Moreover, the projected density of states and the charge density differences of all systems are calculated to explore the mechanism for the enhancement of CO2 reduction performance. These analyses indicate that the localization of electron density on the G2 site makes it be the most active site on the N‐doped graphene sheet for CO2RR. Hence, our computations demonstrate that by both nitrogen doping and LS increasing on the graphene sheet is a promising way for positive modulating its catalytic activity of the CO2RR. [ABSTRACT FROM AUTHOR]

Water splitting is a promising technology for sustainable conversion of hydrogen energy. The rational design of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) bifunctional electrocatalysts with superior activity and stability in the same electrolyte is the key to promoting their large‐scale applications. Herein, an ultralow Ru (1.08 wt%) transition metal phosphide on nickel foam (Ru–MnFeP/NF) derived from Prussian blue analogue, that effectively drivies both the OER and the HER in 1 m KOH, is reported. To reach 20 mA cm−2 for OER and 10 mA cm−2 for HER, the Ru–MnFeP/NF electrode only requires overpotentials of 191 and 35 mV, respectively. Such high electrocatalytic activity exceeds most transition metal phosphides for the OER and the HER, and even reaches Pt‐like HER electrocatalytic levels. Accordingly, it significantly accelerates full water splitting at 10 mA cm−2 with 1.470 V, which outperforms that of the integrated RuO2 and Pt/C couple electrode (1.560 V). In addition, the extremely long operational stability (50 h) and the successful demonstration of a solar‐to‐hydrogen generation system through full water splitting provide more flexibility for large‐scale applications of Ru–MnFeP/NF catalysts. [ABSTRACT FROM AUTHOR]