Porous molybdenum carbide nano-octahedrons synthesized via confined carburization in metal-organic frameworks for efficient hydrogen production

TLDR

Electrochemical water splitting is a promising route to clean hydrogen, yet the scarcity of high‑performance, low‑cost electrocatalysts limits large‑scale adoption, and metal‑organic frameworks offer a tunable platform for creating such materials. This work demonstrates a MOF‑assisted confined carburization strategy to synthesize nanostructured transition‑metal carbides. Using a copper‑based MOF host and molybdenum polyoxometalate guest, mesoporous molybdenum carbide nano‑octahedrons were fabricated, yielding ultrafine nanocrystallites. These nano‑octahedrons show remarkable electrocatalytic activity for hydrogen evolution in both acidic and basic media, providing guidelines for designing nanostructured electrocatalysts.

Abstract

Abstract Electrochemical water splitting has been considered as a promising approach to produce clean and sustainable hydrogen fuel. However, the lack of high-performance and low-cost electrocatalysts for hydrogen evolution reaction hinders the large-scale application. As a new class of porous materials with tunable structure and composition, metal-organic frameworks have been considered as promising candidates to synthesize various functional materials. Here we demonstrate a metal-organic frameworks-assisted strategy for synthesizing nanostructured transition metal carbides based on the confined carburization in metal-organic frameworks matrix. Starting from a compound consisting of copper-based metal-organic frameworks host and molybdenum-based polyoxometalates guest, mesoporous molybdenum carbide nano-octahedrons composed of ultrafine nanocrystallites are successfully prepared as a proof of concept, which exhibit remarkable electrocatalytic performance for hydrogen production from both acidic and basic solutions. The present study provides some guidelines for the design and synthesis of nanostructured electrocatalysts.