Yolk‐Shell‐Structured CuO−ZnO−In 2 O 3 Trimetallic Oxide Mesocrystal Microspheres as an Efficient Catalyst for Trichlorosilane Production

Abstract Trichlorosilane (TCS), the primary chemical feedstock for production of high‐purity Si used in Si‐based solar cells, is currently manufactured industrially via a non‐catalytic hydrochlorination of metallurgical Si. This process generates a huge amount of undesirable silicon tetrachloride (STC) byproduct. Here we report the synthesis of yolk‐shell‐structured CuO−ZnO−In 2 O 3 trimetallic oxide mesocrystal microspheres that can be employed as an efficient catalyst to produce TCS catalytically. The CuO−ZnO−In 2 O 3 microspheres with multiple hetero‐interfaces were prepared using a facile solvothermal reaction followed by calcination. We found that differing from a single CuO mesocrystal, the electronic density on Cu atoms in the CuO phase within CuO−ZnO and CuO−ZnO−In 2 O 3 can be tuned by varying the composition. When used as a catalyst for Si hydrochlorination reaction to produce TCS, CuO−ZnO−In 2 O 3 shows excellent catalytic performance with very high Si conversion and TCS selectivity. Under the same reaction conditions, the TCS yield increased 13 times relative to the catalyst‐free process. This work demonstrates the possibility to decrease the amount of STC needed for the catalytic manufacture of TCS, and provides an approach to the facile synthesis of multi‐component mesocrystal materials with a specific structure.