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Nano Research 2023, 16(4): 4515-4523 https://doi.org/10.1007/s12274-021-3792-2
Research Article | Issue | Published: 19 August 2021

Ru complex and N, P-containing polymers confined within mesoporous hollow carbon spheres for hydrogenation of CO2 to formate

Show Author's Information Guoxiang Yang1,  Yasutaka Kuwahara1,2,3,4,  Kohsuke Mori1,2,3,  Catherine Louis5,  Hiromi Yamashita1,2,3( )
Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
Unit of Elements Strategy Initiative for Catalysts & Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520, Japan
JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface, LRS, F-75005 Paris, France
Keywords:
heterogeneous catalysis, porous organic polymers (POPs), mesoporous hollow carbon spheres, formate synthesis, CO2 hydrogenation
Cite this article:
Yang G, Kuwahara Y, Mori K, et al. Ru complex and N, P-containing polymers confined within mesoporous hollow carbon spheres for hydrogenation of CO2 to formate. Nano Research, 2023, 16(4): 4515-4523. https://doi.org/10.1007/s12274-021-3792-2
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Abstract Full text Electronic supplementary material About this article

The development of reliable catalysts with both excellent activity and recyclability for carbon dioxide (CO2) hydrogenation is challenging. Herein, a ternary hybrid heterogeneous catalyst, involving mononuclear Ru complex, N, P-containing porous organic polymers (POPs), and mesoporous hollow carbon spheres (Ru3+-POPs@MHCS) is reported for CO2 hydrogenation to formate. Based on comprehensive structural analyses, we demonstrated that Ru3+-POPs were successfully immobilized within MHCS. The optimized Ru3+-0.5POPs@MHCS catalyst, which was obtained with about 5 wt.% Ru3+ and 0.5 mmol POPs polymers confined into 0.3 g MHCS, exhibited high catalytic activity for CO2 hydrogenation to formate (turnover number (TON) > 1,200 for 24 h under mild reaction conditions (4.0 MPa, 120 °C)) and improved durability, compared to Ru3+ catalysts without POPs polymers (Ru3+-MHCS) and unencapsulated MHCS (Ru3+-0.5POPs) catalysts. The improved catalytic performance is attributed to the high surface area and large pore volume of MHCS which favors dispersion and stabilization of Ru3+-POPs. Furthermore, the MHCS and POPs showed high CO2 adsorption ability. Ru3+-POPs encapsulated into MHCS reduces the activation energy barrier for CO2 hydrogenation to formate.


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About this article

Ru complex and N, P-containing polymers confined within mesoporous hollow carbon spheres for hydrogenation of CO2 to formate

Show Author's information Guoxiang Yang1, Yasutaka Kuwahara1,2,3,4, Kohsuke Mori1,2,3, Catherine Louis5, Hiromi Yamashita1,2,3( )
Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
Unit of Elements Strategy Initiative for Catalysts & Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520, Japan
JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface, LRS, F-75005 Paris, France

Abstract

The development of reliable catalysts with both excellent activity and recyclability for carbon dioxide (CO2) hydrogenation is challenging. Herein, a ternary hybrid heterogeneous catalyst, involving mononuclear Ru complex, N, P-containing porous organic polymers (POPs), and mesoporous hollow carbon spheres (Ru3+-POPs@MHCS) is reported for CO2 hydrogenation to formate. Based on comprehensive structural analyses, we demonstrated that Ru3+-POPs were successfully immobilized within MHCS. The optimized Ru3+-0.5POPs@MHCS catalyst, which was obtained with about 5 wt.% Ru3+ and 0.5 mmol POPs polymers confined into 0.3 g MHCS, exhibited high catalytic activity for CO2 hydrogenation to formate (turnover number (TON) > 1,200 for 24 h under mild reaction conditions (4.0 MPa, 120 °C)) and improved durability, compared to Ru3+ catalysts without POPs polymers (Ru3+-MHCS) and unencapsulated MHCS (Ru3+-0.5POPs) catalysts. The improved catalytic performance is attributed to the high surface area and large pore volume of MHCS which favors dispersion and stabilization of Ru3+-POPs. Furthermore, the MHCS and POPs showed high CO2 adsorption ability. Ru3+-POPs encapsulated into MHCS reduces the activation energy barrier for CO2 hydrogenation to formate.

Keywords: heterogeneous catalysis, porous organic polymers (POPs), mesoporous hollow carbon spheres, formate synthesis, CO2 hydrogenation

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Publication history
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Acknowledgements

Publication history

Received: 19 May 2021
Revised: 25 July 2021
Accepted: 03 August 2021
Published: 19 August 2021
Issue date: April 2023

Copyright

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2021

Acknowledgements

Acknowledgements

This work was supported by JSPS KAKENHI (Nos. 18K14056 and 19H00838) and JST, PRESTO (No. JPMJPR19T3), Japan. A part of this work was supported by the cooperative research program of “Network Joint Research Center for Materials and Devices” (No. 20211069). We also thank the support of the International Joint Research Promotion Program at Osaka University. G. X. Y. gratefully acknowledges the financial support from the China Scholarship Council (No. 201808310132). Y. K., K. M., and H. Y. thank the Elements Strategy Initiative of MEXT (No. JPMXP0112101003), Japan. The synchrotron radiation experiments for XAFS measurement were performed at the BL01B1 beamline in SPring-8 with approval from JASRI (Nos. 2019B1114 and 2020A1064).

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