Cobalt Sulfide Nanosheet/Graphene/Carbon Nanotube Nanocomposites as Flexible Electrodes for Hydrogen Evolution

Abstract

Flexible three-dimensional (3D) nanoarchitectures have received tremendous interest recently because of their potential applications in wearable electronics, roll-up displays, and other devices. The design and fabrication of a flexible and robust electrode based on cobalt sulfide/reduced graphene oxide/carbon nanotube (CoS2 /RGO-CNT) nanocomposites are reported. An efficient hydrothermal process combined with vacuum filtration was used to synthesize such composite architecture, which was then embedded in a porous CNT network. This conductive and robust film is evaluated as electrocatalyst for the hydrogen evolution reaction. The synergistic effect of CoS2 , graphene, and CNTs leads to unique CoS2 /RGO-CNT nanoarchitectures, the HER activity of which is among the highest for non-noble metal electrocatalysts, showing 10 mA cm(-2) current density at about 142 mV overpotentials and a high electrochemical stability.

Co(OH)2@PANI Hybrid Nanosheets with 3D Networks as High‐Performance Electrocatalysts for Hydrogen Evolution Reaction

“…Recently, some non-Pt metalbased materials have emerged as effi cient HER catalysts, and these catalysts have shown high activities in acidic solutions, which are generally used for water electrolysis in protonexchange membrane (PEM) systems. [4][5][6][7][8][9][10][11] Alkaline electrolysis is an attractive alternative to PEMbased electrolysis because the non-noble metal electrocatalysts involved in alkaline electrolysis tend to be more stable and exhibit relatively high activities for the HER. [ 12,13 ] In addition, alkaline electrolytes generally have a lower vapor pressure so that the electrolyte vapor does not contaminate the hydrogen gas, especially under the higher temperature conditions used during electrolysis.…”

A highly active hydrogen evolution electrocatalyst based on a cobalt–nickel sulfide composite electrode

“…S12 and were fitted using a Randles circuit, consisting of a series resistance (R s ), a charge transfer resistance (R ct ) and a constant phase element (CPE). The R ct gives a measure of the ease of electron transfer at the electrode/electrolyte interface 11 . As reported in Tab.…”

“…34 Catalyst nanostructuring onto conductive substrates is an effective synthetic strategy for increasing the surface area, which leads to an improvement of the HER electrocatalytic activity. 8,10,11 Moreover, the in situ growth of electrocatalytic materials onto binder-free and three-dimensional (3D) substrates plays a crucial role in obtaining composite electrodes with high mechanical stability and strong interface adhesion. 8,11,15 In this work we report a facile synthetic strategy for the fabrication of a multi-phasic cobalt-nickel sulfide HER electrocatalyst supported onto a commercially available Ni foam (Nif).…”

“…8,10,11 Moreover, the in situ growth of electrocatalytic materials onto binder-free and three-dimensional (3D) substrates plays a crucial role in obtaining composite electrodes with high mechanical stability and strong interface adhesion. 8,11,15 In this work we report a facile synthetic strategy for the fabrication of a multi-phasic cobalt-nickel sulfide HER electrocatalyst supported onto a commercially available Ni foam (Nif). Cobalt and nickel sulfide nanoparticles were generated in situ upon thermal pyrolysis of thiourea, due to the formation of reactive sulfurized molecular species that directly react with the metallic atoms.…”

One Pot Synthesis of Nickel Nanoparticles Stabilized on rGO/Polyethyleneimine Aerogel for the Catalytic Hydrogen Generation

“…Preparation of a suitable catalyst for hydrogen production has attracted the attention of many researchers, because hydrogen is an ideal and green fuel that can be a good alternative to fossil fuels [25,26]. Hydrogen has numerous advantages such as recyclability and being non-pollutant [27,28]. However, because of the weak van der Waals interaction between hydrogen and pure carbon-based materials, hydrogen storage is not possible with these materials.…”