Low-temperature purification of phosphine (PH3) using CuO@NC sorbents: simultaneous pollutant removal and Cu3P resource recovery

Abstract

Phosphine (PH₃) is a highly toxic industrial gas widely used in semiconductor manufacturing and fumigation, posing serious environmental and health risks even at low concentrations. Efficient low-temperature removal systems are urgently needed for safe handling and emission control. This study presents a novel CuO@NC-doped sorbent synthesized via direct thermal treatment of urea and copper nitrate for the purification of PH₃ at 90 °C. N and C doping significantly enhanced basic sites and oxygen vacancies, enabling effective capture of acidic and reducing PH₃ gas. The optimized sorbent achieved a breakthrough capacity of 272.54 mg (PH₃) per g, substantially outperforming previously reported materials. Beyond its practical advantages of simple preparation and low cost, this sorbent offers an innovative pathway for resource utilization—the spent material transforms into valuable Cu₃P, which exhibits promising catalytic, bactericidal and photocatalytic properties. This approach demonstrates simultaneous pollutant removal and resource recovery through low-temperature PH₃-CuO@NC reactions.