Molybdenum Oxycarbide Supported Rh‐Clusters with Modulated Interstitial C–O Microenvironments for Promoting Hydrogen Evolution

Abstract

Tuning the microenvironment and electronic structure of support materials is essential strategy to induce electron transfer between supports and active centers, which is of great importance in optimizing catalytic kinetics. In this study, the molybdenum oxycarbide supported Rh‐clusters are synthesized with modulated interstitial C–O microenvironments (Rh/MoOC) for promoting efficient hydrogen evolution in water splitting. Both electronic structure characterizations and theoretical calculations uncover the apparent charge transfer from Rh to MoOC, which optimizes the d‐band center, H2O adsorption energy, and hydrogen binding energy, thus enhancing its intrinsic hydrogen‐evolving activities. In addition, the co‐occurrence of interstitial C and O atoms in MoOC supports plays a vital role in the dissociation reaction of water during the hydrogen‐evolving process. Impressively, the Rh/MoOC exhibits excellent hydrogen‐evolving activities in terms of exceptional turnover frequency values (11.4 and 39.41 H2 s−1 in alkaline and acidic media) and mass activities (21.3 and 73.87 A mg−1 in alkaline and acidic media) at an overpotential of 100 mV, which is more than 40 times higher than that of the benchmark commercial Rh/C catalysts. This work sheds new light on designing water dissociation materials that surpasses most of the reported catalysts.

Design and Performance of Rh Nanocatalysts for Boosted H2 Generation in Alkaline Media

“…For instance, molybdenum oxycarbide-supported Rh clusters (Rh/ MoOC) were fabricated and displayed the characteristic XRD diffraction peaks of cubic-phase MoOC and cubic-phase Rh (Figure 8e). 53 The suitable lattice match between the Rh nanocluster and MoOC maintained the phase separation and produced a stable heterostructure. The Rh K-edge XANES spectrum of Rh/MoOC demonstrated obvious electron transfer from Rh to MoOC (Figure 8f).…”

“…(h) Adsorption free energies of H*. Reproduced with permission from ref . Copyright 2022 Wiley-VCH GmbH.…”

Tunable Structured Metal Oxides for Biocatalytic Therapeutics

“…Besides the above-mentioned metal oxides, plenty of emerged metal oxides, including W 18 O 49 , MoO 3 , and mixed metal oxides, have also been proven as excellent catalysts in recent years. [11,127,128] Fortunately, evidence has illustrated that MoO 3 NPs with the metal catalytic center of sulfite oxidase (SuO x ) can facilitate the transformation of sulfite to sulfate, especially in SuO x deficiency cells, to show SuO x -like activity. Besides, introducing oxygen vacancies into MoO 3 NPs is expected to modulate the defective structures and improve their SuO x activity.…”

Ultralow Ru Single Atoms Confined in Cerium Oxide Nanoglues for Highly‐Sensitive and Robust H2O2‐Related Biocatalytic Diagnosis

“…[ 14–17 ] Compared with their natural counterpart, the transition metal compounds‐based biocatalysts display several merits, such as low cost, tunable electronic and physicochemical properties, [ 18–20 ] and high stability and recyclability. [ 4–21,22 ]…”