# A Biopolymer System Based on Chitosan and an Anisotropic Network of Nickel Fibers in the Hydrogen Evolution Reaction

## TL;DR

A biopolymer system using chitosan and nickel fibers improves hydrogen production efficiency through better electrocatalytic activity.

## Contribution

A novel composite material combining chitosan and anisotropic nickel fibers is introduced for enhanced hydrogen evolution reaction performance.

## Key findings

- The composite material achieved a 213 mV overpotential at 10 mA/cm² current density in the hydrogen evolution reaction.
- The system demonstrated high specific surface area and lateral conductivity, enhancing electrocatalytic activity.
- Chitosan and nickel fiber networks effectively influence charge transfer and electrode reactions.

## Abstract

In this study, we developed a method for creating an active layer based on a composite material consisting of chitosan and an anisotropic network of nickel fibers (Chitosan/Ni + NiFs). Using this chitosan biopolymer matrix and anisotropic network, we achieved a high specific surface area for the catalytic material, high lateral conductivity for the layer, and stable characteristics, ultimately leading to increased overall electrocatalytic activity in the hydrogen evolution reaction (HER). Through linear voltammetry and impedance spectroscopy, we identified the mechanism and kinetics of the HER in the developed system. The overpotential of the electrochemical reaction was 213 mV at a current density of 10 mA/cm2. Chromatographic analysis confirmed the effectiveness of the Chitosan/Ni + NiFs system in the HER. Our results show how the chitosan biopolymer matrix and oriented nickel fiber network influence charge transfer and electrode reactions, as reflected in the activation energies of hydrogen bonds on the electrocatalytic layers. These findings show that it is feasible to combine a biopolymer matrix and an anisotropic nickel fiber network to create effective electrocatalysts. This approach enables the development of environmentally friendly electrolytic hydrogen production technologies.