am9b05645_si_001.pdf (2.96 MB)
Cobalt-Based Nonprecious Metal Catalysts Derived from Metal–Organic Frameworks for High-Rate Hydrogenation of Carbon Dioxide
journal contribution
posted on 2019-07-25, 17:04 authored by Xiaofei Lu, Yang Liu, Yurong He, Andrew N. Kuhn, Pei-Chieh Shih, Cheng-Jun Sun, Xiaodong Wen, Chuan Shi, Hong YangThe
development of cost-effective catalysts with both high activity
and selectivity for carbon–oxygen bond activation is a major
challenge and has important ramifications for making value-added chemicals
from carbon dioxide (CO2). Herein, we present a one-step
pyrolysis of metal organic frameworks that yields highly dispersed
cobalt nanoparticles embedded in a carbon matrix which shows exceptional
catalytic activity in the reverse water gas shift reaction. Incorporation
of nitrogen into the carbon-based supports resulted in increased reaction
activity and selectivity toward carbon monoxide (CO), likely because
of the formation of a Mott–Schottky interface. At 300 °C
and a high space velocity of 300 000 mL g–1 h–1, the catalyst exhibited a CO2 conversion
rate of 122 μmolCO2 g–1 s–1, eight times higher than that of a reference
Cu/ZnO/Al2O3 catalyst. Our experimental and
computational results suggest that nitrogen-doping lowers the energy
barrier for the formation of formate intermediates (CO2* + H* →
COOH* + *), in addition to the redox mechanism (CO2* + * → CO* + O*). This
enhancement is attributed to the efficient electron transfer at the
cobalt–support interface, leading to higher hydrogenation activity
and opening new avenues for the development of CO2 conversion
technology.