Enhanced electrochemical hydrogen storage performance of organophosphonic carboxylic acid-modified multiwalled carbon nanotubes/Bi₂S₃ composite

Abstract

Hydrogen energy, one of the recognized green energy sources, has many advantages, and electrochemical hydrogen storage has been regarded as one of the outstanding energy storage systems. The present research describes that the organophosphonic carboxylic acid-modified multiwalled carbon nanotubes/Bi₂S₃ composite (OPCAMCN/BS) has been produced successfully by a facile solution reaction method, and it has been characterized by Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), and porous structure analysis. Because of the efficient synergistic effect of organophosphonic carboxylic acid-functionalized multiwalled carbon nanotubes and bismuth sulfide, the composite displays excellent electrochemical hydrogen storage and stability performances. The electrochemical hydrogen storage performance of the OPCAMCN/BS electrodes has been measured, and its discharge capacity (950.9 mAh/g) greatly exceeds the relevant values of those two reference materials, and the cycle life of the OPCAMCN/BS electrodes is higher than that of Bi₂S₃ and MWCNTs/BS. Furthermore, the as-synthesized composite OPCAMCN/BS exhibits very low charge transfer resistance which signifies fast electron transfer. Therefore, OPCAMCN/BS is expected to be used as a kind of excellent electrochemical hydrogen storage material and can be applied in the areas of renewable energy to reduce the use of fossil fuels.

Keywords:

• Organo-phosphonic carboxylic acid-modified multiwalled carbon nanotubes
• Bi₂S₃
• composite
• electrochemical hydrogen storage

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work has been supported by the National Natural Science Foundation of China (No. 51673090, 21806070, and 51102127), the Science and Technology Development Plan from Shandong Provincial Education Department (NO. J17KA006), and the Nature Science Foundation of Shandong Province (No. ZR2018PB017).