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Composition-varied Au/PtTe hetero-junction-abundant nanostructures are fabricated by combining interfacial self-assembly and interface-confined transformation strategy, and can be directly used as electrocatalysts of boosting ethanol electrooxidation. [Display omitted] Pt-based multi-metallic electrocatalysts containing hetero-junctions are found to have superior catalytic performance to composition-equivalent counterparts. However, in bulk solution, controllable preparation of Pt-based hetero-junction electrocatalyst is an extremely random work owing to the complexity of solution reactions. Herein, we develop an interface-confined transformation strategy, subtly achieving Au/PtTe hetero-junction-abundant nanostructures by employing interfacial Te nanowires as sacrificing templates. By controlling the reaction conditions, composition-varied Au/PtTe can be easily obtained, such as Au 75 /Pt 20 Te 5 , Au 55 /Pt 34 Te 11 , and Au 5 /Pt 69 Te 26. Moreover, each Au/PtTe hetero-junction nanostructure appears to be an array consisting of side-by-side Au/PtTe nanotrough units and can be directly used as a catalyst layer without further post-treatment. All Au/PtTe hetero-junction nanostructures show better catalytic activity towards ethanol electrooxidation than commercial Pt/C because of the combining contributions of Au/Pt hetero-junctions and the collective effects of multi-metallic elements, where Au 75 /Pt 20 Te 5 exhibits the best electrocatalytic performance among three Au/PtTe nanostructures owing to its optimal composition. This study may provide technically feasible guidance for further maximizing the catalytic activity of Pt-based hybrid catalysts. [ABSTRACT FROM AUTHOR]

In this work, single-atom Ag anchored on nitrogen-doped carbon catalysts are designed to investigate the effect of different N -coordination environments on the ECO 2 RR products pathway. The combination of experiments and theory calculations reveal that the Ag-N 4 -C (pyrrolic N) site facilitates the adsorption of CO 2 to produce CO, whereas Ag-N 3 -C (pyridine N) exhibits the highest binding energy (-4.73 eV) to hold *CO intermediates for dimerization, consequently steering the pathway to ethanol (C 2 H 5 OH) formation with a FE of 42% at −0.97 V vs. RHE. [Display omitted] • Ag N C catalysts with controllable N species and content were prepared. • ECO 2 RR products from CO to C 2 H 5 OH can be regulated. • Ag-N-rGO 0.025 M with pyrrolic N promotes the production of CO. • Ag-N-C 0.05 M with pyridine N facilitates a FE C2H5OH of 42 % at −0.97 V RHE. • Experiments and DFT calculations reveal the structure–activity relationship. The rational modulation of the coordination environment of the active center of single-atom catalysts (SACs) is a potential strategy to improve the activity and selectivity of electrocatalytic CO 2 reduction. We developed a series of single-atom Ag-anchored on N -doped carbon catalysts with different N -coordination environments by regulating the carbon source (glucose/graphene oxide, GO). Results demonstrated that the CO 2 -to-CO/C 2 H 5 OH pathway can be converted through reasonable regulation of the content of pyrrolic N and pyridine N. At a highly dominant pyrrolic N content of 40.0 %, the electrocatalyst of Ag-N-rGO 0.025 M facilitates the formation of CO with a Faradaic efficiency (FE) of 69.7 %. By contrast, when the pyridine N content is 70.5 %, the best Ag-N-C 0.05 M catalyst in the H-cell shows an FE of 42 % for C 2 H 5 OH at −0.97 V vs. RHE; moreover, the FE is stable at 40 % within 31 h. Density functional theory calculations further confirm that the pyrrolic N site is conducive to the conversion of CO 2 to intermediate *CO, whereas pyridine N exhibits the highest binding energy (ΔG = -4.73 eV) to hold *CO intermediates for dimerization, consequently steering the pathway to the formation of C 2 H 5 OH. The results of this study provide novel insights into the rational design of carbon-based SACs based on efficient electrochemical CO 2 reduction reaction and the regulation of CO 2 selectivity and activity for C 2 H 5 OH production. [ABSTRACT FROM AUTHOR]

Self-confinement synthesized Ni@Mo 2 C/CN can stalely achieve 10 mA/cm2 overall urea oxidation with 1.51 V applied voltage due to the mutual promotion effect of Ni and Mo 2 C on UOR activity and HER activity. [Display omitted] • Ni@Mo 2 C/CN catalyst was synthesized via an in situ self-confinement strategy. • A mutual promotion effect of Ni and Mo 2 C on UOR activity and HER activity exists. • An applied voltage of 1.51 V can achieve 10 m A/cm2 stable overall urea oxidation. Efficient hydrogen production from water splitting is crucial for sustainable energy and yet impeded by sluggish anodic water oxidation. Urea oxidation had been considered as an alternative reaction due to its much lower oxidation potential. Rational design of highly efficient cost-effective electrocatalysts for urea oxidation is therefore urgent for hydrogen production from overall urea oxidation. Here, the Ni/Mo 2 C@CN catalyst consisting of a porous carbon shell and a heterojunction Ni/Mo 2 C core was constructed by an in situ self-confinement synthesis strategy. The mutual promotion effect of Ni and Mo 2 C can boost the urea oxidation and hydrogen evolution reactions at the same time. Only 1.51 V applied potential was needed to achieve stable 10 mA/cm2 overall urea oxidation on the Ni/Mo 2 C@CN catalyst. By considering the great stability resulting from the protective effect of the carbon shell, a practical application potential of Ni/Mo 2 C@CN in overall urea oxidation was achieved. [ABSTRACT FROM AUTHOR]