Optimization of the Hydrogen‐Adsorption Free Energy of Ru‐Based Catalysts towards High‐Efficiency Hydrogen Evolution Reaction at all pH

Abstract

The utilization of noble‐metal catalysts for the hydrogen evolution reaction (HER) provides an efficient strategy for hydrogen acquisition. However, exploring catalysts with suitable hydrogen binding strength for the HER process is always of great importance, but extremely challenging. In this work, sulfur and phosphor as electron‐withdrawing elements were incorporated into carbon nanotube (CNT)‐supported Ru catalysts, which were prepared through a facile solution reduction reaction and post thermo treatment. Owing to the suitable electronegativity provided by P and synergistic effects of the carbon nanotubes, the RuP2/CNT achieved a high catalytic performance as a HER electrocatalyst. This may result from the modulation effect of the electronic properties and the depressed adsorption free energy of RuP2. Electrochemical tests present that the RuP2/CNT composite exhibit a small overpotential of 58 mV at 10 mA cm−2 in acidic electrolyte. In a neutral or alkaline environment, the overpotential is 82 and 40 mV, respectively. The RuP2/CNT electrode also possesses stable durability for long‐time cycling, suggesting its remarkable property as promising all‐pH HER catalyst.

Density Functional Theory for Electrocatalysis

“…Section 3 provides several representative descriptors developed by DFT calculations, including the binding energy, formation energy, [24][25][26] d-band center, [27][28][29] scaling relations, [30][31][32][33] e g orbital occupation, [34][35][36] and free energy of adsorption. [37][38][39] Meanwhile, at Section 4, we will describe the practical tools derived from DFT calculations, which are useful for further investigation of the electrocatalytic activity. Section 5 gives a brief introduction of the catalytic mechanisms of specific electrocatalytic reactions, including HER, ORR, CO 2 RR, and NRR.…”

Mechanism for hydrogen evolution from water splitting based on a MoS2/WSe2 heterojunction photocatalyst: a first-principle study

“…They all were close to 0 eV, which indicated that the heterojunction did not have the adsorption effect on hydrogen aer the generation of hydrogen, and the generated hydrogen could actively diffuse and failed to form hydrogen molecules clustered around the active site. 67…”

Ru catalyst supported on nitrogen-doped nanotubes as high efficiency electrocatalysts for hydrogen evolution in alkaline media

“…The C-C, C-C and C-N bonds are derived from the carbon skeleton of polypyrrole carbon nanotubes, and the existence of C-N bond proves that there is N atom doping in the carbon skeleton. 29,30 The weak peak of C]O bond is caused by the absorption of oxygen or carbon dioxide and the oxidation of a small amount of surface metal ruthenium particles. 31 Three typical types of nitrogen elements can be observed in Fig.…”