Grain boundaries modulating active sites in RhCo porous nanospheres for efficient CO2 hydrogenation

• Published in: Nano research Vol. 11; no. 5; pp. 2357 - 2365
• Main Authors: Zheng, Xusheng, Lin, Yue, Pan, Haibin, Wu, Lihui, Zhang, Wei, Cao, Linlin, Zhang, Jing, Zheng, Lirong, Yao, Tao
• Format: Journal Article
• Language: English
• Published: Beijing Tsinghua University Press 01.05.2018; Springer Nature B.V
• Subjects: Accessibility; Atomic/Molecular Structure and Spectra; Biomedicine; Biotechnology; Boundaries; Carbon dioxide; Catalysis; Catalysts; Catalytic activity; Chemistry and Materials Science; Condensed Matter Physics; Grain boundaries; Hydrogenation; Intermediates; Low temperature; Materials Science; Metals; Nanoparticles; Nanospheres; Nanotechnology; Research Article; Rhodium; X ray photoelectron spectroscopy; carbon dioxide; cobalt; grain boundaries; hydrogenation; charge transfer; rhodium
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-017-1841-7

Designing active sites and engineering electronic properties of heterogeneous catalysts are both promising strategies that can be employed to enhance the catalytic activity for CO 2 hydrogenation. Herein, we report RhCo porous nanospheres with a high density of accessible grain boundaries as active sites for improved catalytic performance in the hydrogenation of CO 2 to methanol. The porous nanosphere morphological feature allows for a high population of grain boundaries to be accessible to the reactants, thereby providing sufficient active sites for the catalytic reaction. Moreover, in-situ X-ray photoelectron spectroscope (XPS) results revealed the creation of negatively charged Rh surface atoms that promoted the activation of CO 2 to generate CO 2 δ – and methoxy intermediates. The obtained RhCo porous nanospheres exhibited remarkable low-temperature catalytic activity with a turnover frequency (TOF Rh ) of 612 h –1 , which was 6.1 and 2.5 times higher than that of Rh/C and RhCo nanoparticles, respectively. This work not only develops an efficient catalyst for CO 2 hydrogenation, but also demonstrates a potential approach for the modulation of active sites and electronic properties.