The Cu/TiO2 adsorbent modified by Ce-doping removes trace phosphorus impurities from circular hydrogen of a polysilicon chemical vapor deposition furnace

Abstract

There is an urgent need for efficient and cost-effective adsorbents for the removal of trace hydrogen phosphide (PH3) from the circular hydrogen systems in the polysilicon chemical vapor deposition furnaces. In this study, a straightforward and cost-effective method was used to synthesize a highly efficient adsorbent (Cex-Cuy/TiO2) for PH3 removal using TiO2 as the carrier and CuO as the active substance. Experimental findings demonstrated that optimal Ce doping amounts (nCu:nCe = 20:1) markedly enhanced the adsorbent's performance, with an adsorption capacity reaching as high as 149.14 mg g−1. Material characterization results indicated that Ce positively influenced the uniform dispersion of Cu on the TiO2 surface, and Ce doping increased the adsorbed oxygen content of the adsorbent, consequently enhancing its oxidation performance. The investigation of the reaction mechanism and causes of adsorbent deactivation revealed that the depletion of active substances (CuO) in the adsorbent and the accumulation of products such as Cu3P and phosphates are the primary factors contributing to its deactivation. Furthermore, high-temperature calcination could restore the activity of the adsorbent, indicating its great potential for engineering applications.