Controllable Synthesis of CoS₂@N/S‐Codoped Porous Carbon Derived from ZIF‐67 for as a Highly Efficient Catalyst for the Hydrogen Evolution Reaction

Abstract

A convenient, controllable method to fabricate an electrode is necessary to achieve the practical application of a hydrogen evolution reaction (HER) catalyst. In this work, an electrodeposition–ZIF conversion–sulfuration strategy is developed to produce a CoS2@N/S‐codoped porous carbon (CoS2@NSC/CFP) to drive the HER efficiently. CoS2@NSC/CFP was prepared by the electrodeposition of Co(OH)2 on a carbon fiber paper followed by conversion into ZIF‐67 and subsequent sulfuration with sulfur. The loading of electroactive components can be controlled easily in the range of 0.7–10.0 mg cm−2 by varying electrodeposition time from 5 min to 2 h. The resulting material can be employed directly as a working electrode for the HER and it shows an excellent catalytic activity and stability with an overpotential of 95 mV at 10 mA cm−2 and 158 mV to reach 100 mA cm−2 in an acidic medium. The high efficiency is related intimately to the high dispersion of ultra‐small CoS2 nanoparticles, heteroatom‐codoping, and the 3 D porous network configuration of the carbon fiber paper.

Crystalline‐Water/Coordination Induced Formation of 3D Highly Porous Heteroatom‐Doped Ultrathin Carbon Nanosheet Networks for Oxygen Reduction Reaction

“…The amounts of N and S are 1.5 and 1.4 at%, respectively. NS‐UCNN exhibits remarkable ORR catalytic performance with a high cathodic peak potential (0.75 V) and positive ORR onset potential (0.93 V) and half‐wave potential (0.83 V), which makes it among the best metal‐free ORR electrocatalysts in the literatures, comparable with Pt/C (Figure S37a and Figure c), and better than other ZIF‐derived metal‐containing porous carbons in terms of the onset potential and half‐wave potential (Table S1) ,,. The electron transfer number was 3.73–3.97 for NS‐UCNN with extremely low H 2 O 2 yield (Figure d).…”

“…Among these materials, MOFs, especially, zeolitic imidazolate frameworks (ZIFs), contain abundant heteroatoms, transition metals, and pores. These materials have demonstrated tremendous potential for facile preparation of highly porous heteroatom‐doped carbon‐based electrocatalysts with ample catalytically active sites . To further expose more active sites, it is desirable to construct two‐dimensional (2D) porous carbon nanosheets.…”

“…Heteroatom‐doping (such as N, S, or P) porous carbon‐based electrocatalysts, exhibiting high stability and resistance toward CO poisoning, satisfactory cost, and more exposed active sites, are regarded as one of the most promising Pt alternatives . Various heteroatom‐containing materials have been used as precursors or templates to prepare heteroatom‐doping porous carbons, such as graphene, carbon nanotubes, biopolymers, supramolecular polymers, and metal organic frameworks (MOFs) . Among these materials, MOFs, especially, zeolitic imidazolate frameworks (ZIFs), contain abundant heteroatoms, transition metals, and pores.…”

Electrochemical Energy Conversion and Storage with Zeolitic Imidazolate Framework Derived Materials: A Perspective

“…have demonstrated a controllable strategy to solve this problem. The preformed Co(OH) 2 on CFP were used as suitable reaction sites for added 2‐MeIm ligand to form and deposit ZIF‐67 on the carbon support (Figure a) . The cobalt hydroxide nanosheets were converted to interconnected ZIF‐67 polyhedra with average sizes of 450 nm within 10 min of immersion into a 2‐MeIm solution at room temperature (Figure b,c).…”

Engineering additional edge sites on molybdenum dichalcogenides toward accelerated alkaline hydrogen evolution kinetics

“…10,11 Practically, water electrolysis is more favoured in alkaline media which helps to promote the sluggish oxygen evolution reaction (OER) to achieve a high energy conversion efficiency. [12][13][14][15] However, most earth-abundant electrocatalysts such as transition metal chalcogenides (TMDs), [16][17][18][19][20] nitrides, 21,22 carbides 23,24 and phosphides, [25][26][27][28] despite of the performance comparable to noble metal that they may possess in acid media, exhibit inferior hydrogen evolution reaction (HER) activity in alkaline media due to the sluggish water adsorption/dissociation step. [29][30][31] Molybdenum dichalcogenides (MoS 2 and MoSe 2 ), as typical TMDs, are among the most efficient catalysts for HER in acid media owing to the moderate Gibbs free energy for hydrogen adsorption.…”