Steering CO2 hydrogenation toward C-C coupling to hydrocarbons using porous organic polymer/metal interfaces

Chengshuang Zhou; Arun S Asundi; Emmett D Goodman; Jiyun Hong; Baraa Werghi; Adam S Hoffman; Sindhu S Nathan; Stacey F Bent; Simon R Bare; Matteo Cargnello

doi:10.1073/pnas.2114768119

Steering CO₂ hydrogenation toward C-C coupling to hydrocarbons using porous organic polymer/metal interfaces

Proc Natl Acad Sci U S A. 2022 Feb 15;119(7):e2114768119. doi: 10.1073/pnas.2114768119.

Authors

Chengshuang Zhou¹, Arun S Asundi^{1

2}, Emmett D Goodman^{1

2}, Jiyun Hong³, Baraa Werghi^{1

2

3}, Adam S Hoffman³, Sindhu S Nathan^{1

2}, Stacey F Bent^{1

2}, Simon R Bare^{2

3}, Matteo Cargnello^{4

2}

Affiliations

¹ Department of Chemical Engineering, Stanford University, Stanford, CA 94305.
² SUNCAT Center for Interface Science and Catalysis, Stanford University, Stanford, CA 94305.
³ Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025.
⁴ Department of Chemical Engineering, Stanford University, Stanford, CA 94305; mcargnello@stanford.edu.

Abstract

The conversion of CO₂ into fuels and chemicals is an attractive option for mitigating CO₂ emissions. Controlling the selectivity of this process is beneficial to produce desirable liquid fuels, but C-C coupling is a limiting step in the reaction that requires high pressures. Here, we propose a strategy to favor C-C coupling on a supported Ru/TiO₂ catalyst by encapsulating it within the polymer layers of an imine-based porous organic polymer that controls its selectivity. Such polymer confinement modifies the CO₂ hydrogenation behavior of the Ru surface, significantly enhancing the C₂₊ production turnover frequency by 10-fold. We demonstrate that the polymer layers affect the adsorption of reactants and intermediates while being stable under the demanding reaction conditions. Our findings highlight the promising opportunity of using polymer/metal interfaces for the rational engineering of active sites and as a general tool for controlling selective transformations in supported catalyst systems.

Keywords: CO2 hydrogenation; C–C coupling; polymer/metal interface.