Re‐Dispersion of Platinum From CNTs Substrate to α‐MoC_1 ‐ x to Boost the Hydrogen Evolution Reaction

Abstract

Developing high‐performance electrocatalysts toward hydrogen evolution reaction (HER) is important for clean and sustainable hydrogen energy, yet still challenging. Herein, an α‐MoC1 ‐ x induced redispersing strategy to construct a superior HER electrocatalyst (Pt/CNTs‐N + α‐MoC1 ‐ x) by mechanical mixing of α‐MoC1 ‐ x with Pt/CNTs‐N followed by thermal reduction is reported. It is found that thermo‐activation treatment enables partial Pt atoms to redisperse on α‐MoC1 ‐ x substrate from carbon nanotubes, which creates dual active interfaces of Pt species dispersed over carbon nanotubes and α‐MoC1 ‐ x. Benefiting from the strong electronic interaction between the Pt atom and α‐MoC1 ‐ x, the utilization efficiency of the Pt atom and the zero‐valence state of Pt is evidently enhanced. Consequently, Pt/CNTs‐N + α‐MoC1 ‐ x catalyst exhibits excellent HER activity with low overpotentials of 17 and 34 mV to achieve a current density of 10 mA cm−2 in acidic and alkaline electrolytes, respectively. Density functional theory calculations further reveal that the synergistic effect between Pt and α‐MoC1 ‐ x makes it accessible for the dissociation of water molecules and subsequent desorption of hydrogen atoms. This work reveals the crucial roles of α‐MoC1 ‐ x additives, providing practical solutions to enhance platinum dispersion, and thereby enhance the catalytic activity in HER.

Oxyanion-Coordinated Co-Based Catalysts for Optimized Hydrogen Evolution: The Feedback of Adsorbed Anions to the Catalytic Activity and Mechanism

“…These results demonstrate that the adsorbed VO 4 3– on Co­(OH) 2 can substantially accelerate the kinetics of the water adsorption and dissociation steps. Although H 2 O molecules are more easily dissociated on the Pt(111) surface (with a barrier of 0.8–1.1 eV), − the production cost of Co­(OH) 2 -VO 4 3– is lower. In general, the calculated results can explain the experimental phenomena well.…”

Bottom‐Up Film‐to‐Bulk Assembly Toward Bioinspired Bulk Structural Nanocomposites

“…The distribution of structural units (such as micropores) is tightly related to the local properties of macroscopic materials. [132] Like the site-specific composition variation, the site-specific pore distribution variation (in terms of structure) can also result in varying mechanical properties, including strength, stiffness, toughness, etc., in specific locations to meet the requirements of application scenarios needing heterogeneous stress and strain. [1,132,133] Yu et al [107] took advantage of the film-to-bulk assembly strategy, fabricating gradually changed heterogeneous bioinspired nacre-like layered bulk structural ceramic scaffold and nanocomposite with designed site-specific pore distribution.…”

“…[132] Like the site-specific composition variation, the site-specific pore distribution variation (in terms of structure) can also result in varying mechanical properties, including strength, stiffness, toughness, etc., in specific locations to meet the requirements of application scenarios needing heterogeneous stress and strain. [1,132,133] Yu et al [107] took advantage of the film-to-bulk assembly strategy, fabricating gradually changed heterogeneous bioinspired nacre-like layered bulk structural ceramic scaffold and nanocomposite with designed site-specific pore distribution. They first prefabricated a series of nacre-like layered structural composite microfilms with different ratios of alumina nanosheets to kaolin nanoparticles via evaporation-induced self-assembly.…”