Ultrafine Cobalt‐Doped Iron Disulfide Nanoparticles in Ordered Mesoporous Carbon for Efficient Hydrogen Evolution

Abstract

Designing earth‐abundant and efficient electrocatalysts to replace noble metals is highly desired for the hydrogen evolution reaction (HER) in water electrolysis. In this study, we constructed a self‐supported electrode with ordered mesoporous carbon film coated carbon fibers as a substrate and Co doped FeS2 nanoparticles as catalytically active phase for the HER. The ordered mesoporous carbon served as nanoreactor to restrict the growth of sulfide particles and prevent them from agglomeration, leading to the formation of ultrafine and highly dispersed sulfide of ∼5 nm, which enables the exposure of abundant active sites. Meanwhile, the Co atom doping enhanced the adsorption of the catalyst towards hydrogen, thereby improving its intrinsic activity. As a result, the electrode exhibited outstanding catalytic activity for the HER in acid electrolyte, manifesting a current density of 10 mA cm−2 at an overpotential of 92 mV and a small Tafel slope of 59 mV dec−1.

Mesoporous Carbon Materials for Electrochemical Energy Storage and Conversion

“…The current density only decayed 5.7 % after a long operation time of 20 hours at an overpotential of 70 mV. Similar designs have been widely used and effectively improved the performance of noble‐metal‐free HER catalysts [298,299] …”

“…Similar designs have been widely used and effectively improved the performance of noble-metal-free HER catalysts. [298,299] The outstanding dispersion and particle size reduction function of mesoporous carbon can also easily be extended to the design of noble-metal-free OER catalyst. With the assistance of ordered mesoporous structure as nano-reactor, Zhang et al have loaded Rock salt type NiCo 2 O 3 on ordered mesoporous carbon.…”

Interfacial Assembly and Applications of Functional Mesoporous Materials

“…Besides, the synthesis of non-noble metal catalysts to substitute Pt is an alternative. Until now, a wide range of non-noble metal mesoporous catalysts, including carbons, metal oxides, metal sulfides, , metal nitrides, metal carbides, and their composites, ,, have been fabricated. For example, hierarchically ordered porous N-doped carbon with single-atomic Co sites, which possesses high porosity and good conductivity, was prepared .…”

Self‐Supported Mesoporous Iron Phosphide with High Active‐Site Density for Electrocatalytic Hydrogen Evolution in Acidic and Alkaline Media

“…Among various hydrogen production methods, electrochemical water splitting is a sustainable and efficient technology to obtain hydrogen energy [2–4] . However, the high operation overpotentials and sluggish kinetic severely limit the hydrogen evolution reaction (HER), therefore requiring highly efficient catalysts to accelerate reaction kinetics and decrease overpotential [5–8] . In general, platinum (Pt) group materials are recognized as the benchmark HER electrocatalysts.…”