Immobilized Single Molecular Molybdenum Disulfide on Carbonized Polyacrylonitrile for Hydrogen Evolution Reaction

Abstract

Designing a MoS2 catalyst having a large number of active sites and high site activity enables the catalytic activity toward the hydrogen evolution reaction to be improved. Herein, we report the synthesis of a low-cost and catalytically active immobilized single molecular molybdenum disulfide on carbonized polyacrylonitrile (MoS2-cPAN) electrocatalyst. From the extended X-ray absorption fine structure spectra analysis, we found that the as-prepared material has no metal–metal scattering and it resembles MoS2 with a molecular state. Meanwhile, the size of the molecular MoS2 has been estimated to be about 1.31 nm by high-angle annular dark-field scanning transmission electron microscopy. A low coordination number and maximum utilization of the single molecular MoS2 surface enable MoS2-cPAN to demonstrate electrochemical performance significantly better than that of bulk MoS2 by two orders of exchange current density (j o) and turnover frequency to the hydrogen evolution.

Microenvironment modulation of single-atom catalysts and their roles in electrochemical energy conversion

“…For instance, carbonized polyacrylonitrile-immobilized single molecular MoS 2 (MoS 2 -cPAN) was demonstrated with much higher turnsover frequency (TOF) to HER than bulk MoS 2 (Fig. 5A) (116). Qi et al (117) recently developed an interface SAC with atomic cobalt array bound to distorted 1T MoS 2 (Co-MoS 2 ) that achieves Pt-like HER activity with high catalytic stability.…”

“…For instance, carbonized polyacrylonitrile-immobilized single molecular MoS 2 (MoS 2 -cPAN) was demonstrated with much higher turnsover frequency (TOF) to HER than bulk MoS 2 ( Fig. 5A ) ( 116 ). Qi et al .…”

“… ( A ) Immobilized single molecular MoS 2 on carbonized polyacrylonitrile for HER, adapted with permission from Zeleke et al . ( 116 ). ( B ) The electron charge of a single Co atom and adjacent S as a function of Co coverage in Co-MoS 2 SAC, ( C ) calculated free energy diagram of HER for Co-MoS 2 SAC with different atomic Co loading amounts, adapted with permission from Qi et al .…”

Defects Enhance the Electrocatalytic Hydrogen Evolution Properties of MoS2‐based Materials

“…The conductivity of 2H-MoS 2 can be improved by supporting it with a conductive material with excellent electron transport properties and chemical stability. [18,39,40] Nevertheless, the contact between the conductive carbon support and MoS 2 still limits the electron transport efficiency during electrocatalysis. Defect engineering can tune the surface electron state to improve the conductivity of the carbon support further.…”

Graphdiyne: A Rising Star of Electrocatalyst Support for Energy Conversion

“…In addition, the massive combustion of fossil fuels also brings severe environmental disruptions such as global warming and particulate–matter pollution. [ 1 ] It is worth noting that carbon dioxide in the atmosphere is growing year by year and its content now is approximate twofold larger than that before industrial revolution. [ 2 ] Consequently, it is urgent to develop economical, high‐performance, and environmentally benign technologies for energy conversion in response to the increasing global energy supply and environment deterioration.…”