Progress in the Study of TransitionMetal-Based Carbon Nanotube Composites for Electrochemical Hydrogen Evolution

Abstract

Hydrogenis an efficient, clean, and economical energy source, primarily due to itsremarkably high energy density. Electrolytic water is considered an attractiveand feasible method for hydrogen production. The high cost and scarcity oftraditional Pt-based catalysts limit their large-scale application. Transitionmetals (TMs)-based composites, particularly those integrated with carbonnanotubes (CNTs), have emerged as promising alternatives due to their highconductivity, surface area, and ability to enhance the catalytic properties ofTMs. Currently, there is no systematic summary of TMs-based CNTs composites forelectrochemical hydrogen evolution reaction (HER). In this review, the mainsynthesis methods, including the wet chemical method, chemical vapordeposition, and electrochemical techniques, were first summarized. Then, thelatest advancements of TMs/CNTs composites, focusing on their structure,electronic properties and superior HER catalytic performance, weresystematically discussed. The catalytic mechanisms are meticulously examined,with particular emphasis on the pivotal role of CNTs in enhancing chargetransfer and stabilizing metal nanoparticles. Finally, this review addressesthe current challenges and future development directions for HER catalysts.

Keywords

Carbon nanotubes / Transition metals / Composites / Hydrogen evolution reaction

Author Contributions

Conceptualization, J.Z., L.Z. and L.J.; Methodology, Y.Y.; Software, Q.Z.; Formal Analysis, J.Z.; Investigation, J.Z.; Resources, J.Z. and G.Z.; Data Curation, G.Z.; Writing—Original Draft Preparation, J.Z.; Writing—Review & Editing, G.Z.; Visualization, L.Z.; Funding Acquisition, G.Z.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Funding

This work was supported by the Natural Science Foundation of Hebei Province (grant no. E2025209079) and Key Research Project of North China University of Science and Technology (grant no. ZD-YG-202301).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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