# Preparation and Performance Optimization of Fe2+:ZnSe Solid Solution by High-Pressure–High-Temperature Method

## TL;DR

Researchers optimized the performance of iron-doped zinc selenide polycrystals using high-pressure and high-temperature methods to improve their structural and mechanical properties.

## Contribution

A novel HPHT secondary sintering method is introduced to enhance Fe2+ doping and crystal quality in ZnSe polycrystals.

## Key findings

- Iron ions (Fe2+) successfully doped ZnSe crystals but with low concentration and many defects.
- HPHT secondary sintering reduced crystal defects and improved Fe2+ distribution and concentration.
- The method enhanced the density and hardness of the polycrystalline ceramics.

## Abstract

In this paper, high-purity zinc selenide (ZnSe) prepared by the Chemical Vapor Deposition (CVD) method was used as the raw material, and iron ion-doped zinc selenide polycrystals were successfully fabricated through the thermal diffusion method at 1100 °C for 30 h. The results showed that iron ions (Fe2+) successfully penetrated into the zinc selenide crystals, but the concentration of iron ions inside the crystals was relatively low, and the crystals exhibited numerous defects. To address this issue, we performed secondary sintering and annealing on the samples under high-temperature and high-pressure (HPHT) conditions, with the annealing temperature range set at 900–1200 °C. The results demonstrated that, under the synergistic effects of high temperature and high pressure, the lattice spacing in the crystals significantly decreased, defects were reduced, the distribution of iron ions became more uniform, and the concentration of iron ions in the central region increased. Additionally, the density and hardness of the samples were significantly improved. The method of secondary sintering under high-temperature and high-pressure provides a novel approach for the preparation of iron ion-doped zinc selenide polycrystalline ceramics, contributing to the enhancement of ceramic properties.