Oxygen-Bridged Stabilization of Single Atomic W on Rh Metallenes for Robust and Efficient pH-Universal Hydrogen Evolution

Abstract

Highly efficient and durable electrocatalysts are of the utmost importance for the sustainable generation of clean hydrogen by water electrolysis. Here, we present a report of an atomically thin rhodium metallene incorporated with oxygenbridged single atomic tungsten (Rh−O−W) as a high-performance electrocatalyst for pH-universal hydrogen evolution reaction. The Rh−O−W metallene delivers ascendant electrocatalytic HER performance, characterized by exceptionally low overpotentials, ultrahigh mass activities, excellent turnover frequencies, and robust stability with negligible deactivation, in pH-universal electrolytes, outperforming that of benchmark Pt/ C, Rh/C and numerous other reported precious-metal HER catalysts. Interestingly, the promoting feature of −O−W single atomic sites is understood via operando X-ray absorption spectroscopy characterization and theoretical calculations. On account of electron transfer and equilibration processes take place between the binary components of Rh−O−W metallenes, fine-tuning of the density of states and electron localization at Rh active sites is attained, hence promoting HER via a near-optimal hydrogen adsorption.

Ultrathin Rh Nanosheets with Rich Grain Boundaries for Efficient Hydrogen Oxidation Electrocatalysis

“…Furthermore, X-ray photoelectron spectroscopy (XPS) was further conducted to investigate the chemical state and electronic state of the Rh-GB NSs. As exhibited in Figure S5, the main peaks at 307.1 and 311.9 eV corresponded to 3d 5/2 and 3d 3/2 peaks of metallic Rh, respectively. , The peaks at approximately 307.8 and 313.1 eV were assigned to Rh 3+ , which can be attributed to surface oxidation when exposed to air. The peak areas indicated that metallic Rh was the predominant species in the Rh-GB NSs.…”

Stabilizing Low‐Valence Single Atoms by Constructing Metalloid Tungsten Carbide Supports for Efficient Hydrogen Oxidation and Evolution

“…The total density of states (DOS) of the Ru-WC x catalyst shows a higher occupation at the Fermi level compared with WC x and Ru, suggesting that the electronic coupling between Ru and W atoms reduces the charge transfer resistance (Figure 5c). [26] Noticeably, the d-band center of Ru-WC x (Ru) is lower than metallic Ru in the partial density of states (PDOS) plot (Figure 5d and 5e). Based on the d-band theory, the decline of the d-band center implies that the adsorption of reaction intermediates on the Ru site is weakened, promoting the subsequent evolution steps of H 2 O or H 2 .…”

Surface engineering for stable electrocatalysis

“…Fourier-transformed and wavelet-transformed EXAFS commonly reveals changes in intensity and radial distance of metal–oxygen and metal–metal coordination, presenting an insightful picture of the catalyst's structural evolution under electrochemical conditions. 75,76 With the aid of in situ Raman 77,78 and in situ Fourier transform infrared spectroscopies 79 in probing the formation of oxygenated and carbonated species, the dynamic chemistry of the electrified interface can be fully unravelled.…”