IrMo Nanocluster-Doped Porous Carbon Electrocatalysts Derived from Cucurbit[6]uril Boost Efficient Alkaline Hydrogen Evolution

Abstract

Electrocatalysts based on noble metals have been proven efficient for high-purity hydrogen production. However, the sluggish kinetics of the hydrogen evolution reaction (HER) in alkaline media caused by high water dissociation energy largely hampers this electrochemical process. To improve the electrocatalytic activity, we fabricate an effective porous carbon matrix derived from cucurbit[6]uril using a template-free method to support iridium–molybdenum (IrMo) nanoclusters. As proof of concept, the resulting IrMo-doped carbon electrocatalyst (IrMo-CBC) was found to boost the alkaline HER significantly. Owing to the unique in-plane hole structure and the nitrogen-rich backbone of cucurbit[6]uril as well as the ultrafine IrMo nanoclusters, IrMo-CBC exhibits pronounced alkaline HER activity with an extremely low overpotential of 12 mV at 10 mA cm–2, an ultrasmall Tafel slope (28.06 mV dec–1), a superior faradic efficiency (98%), and a TOF of 11.6 H2 s–1 at an overpotential of 50 mV, outperforming most iridium-based electrocatalysts and commercial Pt/C.

Three-dimensional N, P, and O tri-doped porous carbon for multifunctional electrocatalytic reactions

“…1f), which is in favor of the transport of electrolytes and liberation of gas to enhance the electrocatalytic activity. 36,37 The corresponding elemental mapping of 3D-NPOC showcases that the C, N, O, and P elements are evenly distributed in the whole framework of 3D-NPOC (Fig. 1g), well consistent with the XPS spectrogram results, which also indicates the successful preparation of the N, P, O co-doped carbon material.…”

Design Strategies towards Advanced Hydrogen Evolution Reaction Electrocatalysts at Large Current Densities

“…Therefore, in the alkaline solution, the first Volmer step is water dissociation to produce H*, which surely introduce an extra energy barrier for HER. [47][48][49] Then one H* reacts with one water and an electron to produce H 2 (Heyrovsky step), or two adjacent H* form H 2 (Tafel step).…”

FeCoNiW medium entropy alloys loaded onto N-doped carbon skeletons as efficient electrocatalysts for oxygen evolution reactions

“…Nitrogen doped carbon materials are recognised as excellent conductive substrates due to their high surface area, adequate porosity and good electrochemical stability. 29 The incorporation of the transition metal W greatly improves the hydrolysis performance of the catalysts while tuning the electronic structure of the FeCoNi alloys. As a result of the above analysis, the present work introduces a fourth transition metal, W, in the FeCoNi alloy.…”