Atomically synergistic Zn-Cr catalyst for iso-stoichiometric co-conversion of ethane and CO2 to ethylene and CO
Ji Yang, Lu Wang, Jiawei Wan, Farid El Gabaly, André Luís Fernandes Cauduro, Bernice Mills, Jeng‐Lung Chen, Liang‐Ching Hsu, Daewon Lee, Xiao Zhao, Haimei Zheng, Miquel Salmerón, Caiqi Wang, Zhun Dong, Hongfei Lin, Gábor A. Somorjai, Fabian Rosner, Hanna Breunig, David Prendergast, De‐en Jiang, Seema Singh, Ji Su
Abstract
Abstract Developing atomically synergistic bifunctional catalysts relies on the creation of colocalized active atoms to facilitate distinct elementary steps in catalytic cycles. Herein, we show that the atomically-synergistic binuclear-site catalyst (ABC) consisting of $${{{{{\rm{Zn}}}}}}^{\delta+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>Zn</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>δ</mml:mi> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:math> -O-Cr 6+ on zeolite SSZ-13 displays unique catalytic properties for iso-stoichiometric co-conversion of ethane and CO 2 . Ethylene selectivity and utilization of converted CO 2 can reach 100 % and 99.0% under 500 °C at ethane conversion of 9.6%, respectively. In-situ/ex-situ spectroscopic studies and DFT calculations reveal atomic synergies between acidic Zn and redox Cr sites. $${{{{{\rm{Zn}}}}}}^{\delta+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>Zn</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>δ</mml:mi> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:math> ( $$0 \, < \, \delta \, < \, 2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mn>0</mml:mn> <mml:mspace/> <mml:mo><</mml:mo> <mml:mspace/> <mml:mi>δ</mml:mi> <mml:mspace/> <mml:mo><</mml:mo> <mml:mspace/> <mml:mn>2</mml:mn> </mml:math> ) sites facilitate β-C-H bond cleavage in ethane and the formation of Zn-H δ - hydride, thereby the enhanced basicity promotes CO 2 adsorption/activation and prevents ethane C-C bond scission. The redox Cr site accelerates CO 2 dissociation by replenishing lattice oxygen and facilitates H 2 O formation/desorption. This study presents the advantages of the ABC concept, paving the way for the rational design of novel advanced catalysts.