# Exploring Selenide Synthesis Pathways for Optimizing Energy Conversion

## TL;DR

This paper explores how different combinations of nickel, cobalt, and iron selenides affect their structure and electrochemical performance, aiming to improve energy conversion.

## Contribution

The study reveals how varying d-block metal ratios influences structural stability and electrochemical behavior of selenides.

## Key findings

- Quaternary selenides with higher d-block metal content show increased structural entropy and stability.
- Nickel selenide-based samples have the highest electrochemically active surface area.
- Balanced ratios of nickel, cobalt, and iron enhance electrode stability.

## Abstract

This study investigated the structural and electrochemical characteristics of binary and quaternary systems comprising nickel, cobalt, and iron selenides. The powders were obtained via a solvothermal route. X-ray diffraction (XRD) and Raman spectroscopy revealed significant phase diversity. It was observed that increasing the proportion of d-block metals in quaternary systems enhances structural entropy, potentially leading to more homogeneous and stable structures dominated by energetically preferred components such as nickel. The electrochemical analysis indicated that the binary system exhibited a reversible redox reaction, with nickel selenide-based samples demonstrating the highest electrochemically active surface area. Quaternary systems display varying degrees of electrochemical stability. An equal contribution of nickel, cobalt, and iron appears beneficial in achieving stable electrodes. This research contributes to understanding the relationship between transition metal selenides’ structural, morphological, and electrochemical properties, providing insights into their potential applications in hydrogen generation.