Fan Yurui, Wang Mingming, Liu Zhisong, Gao Guanqun, Qi Hongyuan, Huang Wenjun, Ma Lei, Qu Zan, Yan Naiqiang, Xu Haomiao
School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
State Key Laboratory Incubation Base for Green Processing of Chemical Engineering, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, P. R. China.
ACS Nano. 2024 Jul 26. doi: 10.1021/acsnano.4c06094.
Ru-based catalysts have emerged as promising alternatives to HgCl in vinyl chloride monomer (VCM) production by acetylene hydrochlorination. However, poor CH activation and the generation of key intermediates (*CH═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 CH 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═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 CH activation in industrial applications.
在乙炔氢氯化法生产氯乙烯单体(VCM)过程中,钌基催化剂已成为氯化汞颇具前景的替代物。然而,较差的C-H活化以及关键中间体(CH═CH)的生成对提高催化性能构成了巨大挑战。在此,我们采用晶格应变工程策略合成了一种镍插层钌异质结构,从而得到了理想的电子和化学环境。镍的协同作用通过减弱强大的空间位阻分裂了C-H和HCl的吸附中心,还促进了线性C≡C构型的活化。精确控制的晶格应变使得镍和钌之间形成了强烈的d-d杂化相互作用,导致d带中心从-3.72 eV(对于Ru/C)上移至-3.49 eV并实现电子离域。这种优化的局部Ni-Ru/C结构因此增强了H吸附,同时降低了生成*CH═CH中间体的能垒。此外,VCM形成的能垒也同时降低。相应地,Ni-Ru/C异质结构在中试试验中表现出改进的性能,转化率>99.2%且稳定性超过500小时。这些性能显著超过了大多数已报道的钌基部分和传统汞催化剂,为工业应用中的C-H活化提供了一条有前景的途径。