Reduced Graphene Oxide‐Modified Carbon Nanotube/Polyimide Film Supported MoS₂ Nanoparticles for Electrocatalytic Hydrogen Evolution

Abstract

wileyonlinelibrary.comAs a typical transition-metal dichalcogenide, MoS 2 is a promising electrocatalyst for HER. Both computational and experimental results have confi rmed that the HER activity of MoS 2 stemmed from the sulfur edges, whereas the basal planes were catalytically inert. [ 16,17 ] As a result, nanosized MoS 2 should be more active for HER electrocatalysis than the relatively inert bulk forms due to the presence of more exposed sulfur edges. Besides, the electrical conductivity of catalysts is crucial to the catalytic activity because a high conductivity can ensure a fast electron transfer during a catalytic process. [ 18,19 ] It is well-known that MoS 2 exhibits poor intrinsic conductivity originated from its large bandgap, [ 20 ] which signifi cantly limits the overall HER rate. The past years have witnessed expanding endeavors in improving the conductivity of MoS 2 -based electrocatalysts. Carbon materials have been widely used to improve the catalytic activity of MoS 2 , relying on their unique physicochemical properties. Dai and coworkers synthesized MoS 2 /RGO composite and achieved high HER catalytic activity at a low overpotential. [ 21 ] Chorkendorff and co-workers reported a highly active and stable carbon fi bre/ MoS x composite for electrochemical hydrogen evolution. [ 22 ] Cheng and co-workers synthesized CoS 2 /RGO-CNT composites for high effi cient HER electrocatalysts. [ 23 ] Such fi ndings suggest the signifi cance of carbon materials in HER electrocatalysis. MoS 2 /carbon composites have been successfully applied for the electrocatalytic HER, where carbon materials play the role of hosting MoS 2 as well as enhancing the conductivity of the composites.Although the HER properties of MoS 2 /carbon composites have been investigated, the electrocatalytic activity of MoS 2 supported on carbon materials in the form of a conducting polymer fi lm has not been studied. In this work, we synthesized MoS 2 on the reduced graphene oxide-modifi ed carbon nanotube/ polyimide (PI/CNT-RGO) fi lm by an electrochemical method. CNT can greatly improve the mechanical and electrical properties of CNT/polymer composites, leading to the good conductivity and mechanical properties of PI/CNT fi lm. [ 24,25 ] PI/CNT fi lm can be used over a wide temperature range of −200 to 300 °C and in the condition of strong acid or alkaline. We prepared PI/CNT fi lm and modifi ed the fi lm with RGO which further improved the conductivity of PI/CNT fi lm and affected the morphology of

3D Graphene Aerogels Decorated with Cobalt Phosphide Nanoparticles as Electrocatalysts for the Hydrogen Evolution Reaction

“…The Tafel slopes of CoP‐9/GA, CoP‐12/GA, and CoP‐15/GA were 62 mV dec −1 , 50 mV dec −1 , and 61 mV dec −1 , respectively, which were smaller than that of CoP MPs (86 mV dec −1 ). These values reveal that the HER on CoP‐ x /GA proceeds through a Volmer–Heyrovsky mechanism, in which the fast discharge of a proton is followed by a rate‐limiting electrochemical recombination with an additional proton . The exchange current density ( j 0 ), calculated by using the extrapolation method on the Tafel plots, was employed to evaluate the inherent HER activity .…”

Design, synthesis, and energy-related applications of metal sulfides

“…Since then, many conductive templates such as carbon nanofibers foam, 179 nanoporous metals, 180 and graphene additives, are becoming ascendant. 181 Aside from MoS 2 , other molybdenum sulfides-based materials were also researched in recent years. Hu's group described a feasible solution-based chemical approach to synthesize amorphous MoS 3 particles as efficient HER catalysts, 153 185 Similarly, Jin and co-workers presented a fast microwaveassisted chemical exfoliation method to prepare 1T-WS 2 nanosheets.…”

Role of Organic Components in Electrocatalysis for Renewable Energy Storage

“…[39] Thus, conducting polymers are considered to be ap romising matrix that can both stabilize the catalysts and enhance conductivity.I na ddition, conducting polymers could show catalytic activities without other components. The conductivityo f catalysts is ak ey factor in catalytic processes to ensure electron transport, but many efficient electrocatalysts for the HER, such as MoS 2 ,s howp oor conductivity.…”