# Molecular Covalent Functionalization of Graphene and Its Derivatives: An Effective Strategy to Boost Electrocatalytic HER

## TL;DR

This paper reviews how covalent functionalization of graphene improves its electrocatalytic performance for hydrogen production.

## Contribution

The paper provides the first comprehensive review on molecular covalent functionalization of graphene for HER electrocatalysis.

## Key findings

- Covalent functionalization enhances graphene's electronic structure and surface properties for better HER performance.
- Synergistic effects between graphene support, linkers, and functional molecules improve electrocatalytic activity.
- Key characteristics like conductivity and stability are critical for effective HER electrocatalysts.

## Abstract

Graphene-based electrocatalysts
have been developed, and they exhibited
enhanced activity due to their superior electronic conductivity. The
robustness of such graphene materials can be further enhanced by altering
their chemical and physical properties using different techniques.
Molecular covalent functionalization is one of the effective strategies
to alter the chemical composition, electronic structure, surface area,
as well as dispersibility of graphene materials. Despite the significant
literature on its contribution to improving the electrocatalytic activity
for the hydrogen evolution reaction (HER), there is no review article
available. Therefore, we have tried to fill this void by examining
recent developments in the field of molecular covalent functionalized
graphene and its derivatives for water electrolysis. We have also
thoroughly discussed the role of individual components (graphene support,
linker, and functional molecules bearing the main active sites) to
improve the performance of the electrocatalyst by inducing synergistic
effects and enriching surface properties. Moreover, the main characteristics
of effective electrocatalysts, such as the surface area, functionality,
dispersibility, conductivity, stability, and electronic structure,
have also been reviewed. Finally, challenges and future perspectives
are outlined to assist researchers in designing more effective electrocatalysts
for the HER.