SiO₂-supported Au-Ni bimetallic catalyst for the selective hydrogenation of acetylene

Supported Au catalysts have been reported to exhibit high ethylene selectivity in the hydrogenation of acetylene, but the conversion is relatively low. Adding a second metal to Au has proven to be a promising approach to enhance its catalytic performance in acetylene hydrogenation. In this work, SiO₂-supported Au-Ni bimetallic catalysts were synthesized and investigated in the selective hydrogenation of acetylene. The Au-Ni bimetallic catalysts exhibited much higher catalytic performance than that of the corresponding monometallic Au or Ni catalysts. By tuning the reduction temperature and/or Ni loading, we obtained an Au-Ni/SiO₂ catalyst with optimal performance. The results of transmission electron microscopy imaging revealed that the Au-Ni bimetallic particles were highly dispersed on the SiO₂ support. Meanwhile, analysis of the bimetallic catalyst by energy-dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy demonstrated the formation of Au-Ni alloy, which contributed to the synergistic effect between Au and Ni in the hydrogenation of acetylene.