Lattice-Strain Engineering in Ni–Ru Heterostructures for Efficient Acetylene Hydrochlorination toward Vinyl Chloride

Abstract

Ru-based catalysts have emerged as promising alternatives to HgCl 2 in vinyl chloride monomer (VCM) production by acetylene hydrochlorination. However, poor C 2 H 2 activation and the generation of key intermediates (*CH 2 �CH) have posed grand challenges for enhanced catalytic performances. Herein, we synthesized a Ni-intercalated Ru heterostructure using a lattice-strain engineering strategy, resulting in the desired electronic and chemical environments. The collaboration of Ni splits the adsorption centers of C 2 H 2 and HCl by weakening the strong steric hindrance, and it also promotes the activation of the linear C�C configurations. The well-controlled lattice strain enables strong d−d hybridization interactions between Ni and Ru, resulting in an upshift of the d-band center from −3.72 eV (for Ru/C) to −3.49 eV and electronic delocalization. This optimized local Ni−Ru/C structure thus enhances *H adsorption while weakening the energy barrier for generating *CH 2 �CH intermediates. Furthermore, the energy barrier for VCM formation was simultaneously reduced. Accordingly, the Ni−Ru/C heterostructures achieve improved performance in pilot-scale trials, with a conversion of >99.2% and stability for over 500 h. These performances significantly surpass most reported Ru-based moieties and the traditional Hg catalysts, offering a promising avenue for C 2 H 2 activation in industrial applications.