Engineering Synergistic Sites in a Cerium-Based Metal–Organic Framework for Photocatalytic CO2 Reduction
Zhaozhao Hu, Siyu Zhou, Xin Lian, Jiarui Fan, Yukun Ye, Lifei Lin, Benjamin J. Moore, Yuanjun Wang, Ruohan Li, Zhixin Wang, Sarah J. Day, Luke Keenan, Mark D. Frogley, Tian Luo, Xue Han, Jiangnan Li, Sihai YangAbstract
Photoreduction of CO2 to produce solar fuels is an important target. Redox-active Ce-based metal–organic frameworks (MOFs) are promising catalysts. Herein, we have synthesized an amino-functionalized Ce-based MOF, PKU-167 (PKU = Peking University). Upon introduction of Co(bpy)2Cl2 (bpy = 2,2′-bipyridine) to the skeleton of PKU-167, PKU-167-0.9Co achieved a high CO production rate of 18.4 mmol g–1 h–1 with a selectivity of 91.8% under visible-light irradiation and an apparent quantum yield of 1.97% at 425 nm. In situ characterizations and modeling reveal a synergistic adsorption–reduction mechanism, where amino groups enrich adsorption of CO2 for subsequent photoreduction on {Ce6} clusters and Co2+ sites in concert to achieve the optimal photocatalytic performance. This study will advance the rational design of redox-active Ce-based MOFs as efficient photocatalysts.