Inductive effect in amino functionalized ionic liquids modified TS-1 nanosheets for efficiently sunlight-driven CO2 reduction

Photocatalytic technology for converting CO 2 into useful chemicals or clean energy is an effective strategy to solve today's energy and environmental problems. In this study, we present a direct photocatalytic pathway for the conversion of CO 2 -to-CO involving the formation and activation of carboxyl intermediates over amino-functionalized ionic liquid (3-aminopiperidine hydrochloride, [3APip]Cl)-modified titanium silicalite-1 (TS-1) molecular sieve nanosheets . Various in-situ characterizations reveal that the key to activating this pathway lies in the CO 2 adsorption capacity and the efficiency of photoexcited charge migration induced by [3APip]Cl in the hybrid catalyst. In the above catalytic pathway, CO 2 molecules are first adsorbed on the surface of the [3APip]Cl/TS-1 hybrid catalyst under the induction of amino groups in the ionic liquid. Then, these adsorbed CO 2 are activated and transformed into carboxyl intermediate, which can be further converted into CO and CH 4 through photoexcited electrons captured by [3APip]Cl. Based on the results of CO 2 reduction performance, the optimized [3APip]Cl/TS-1 hybrid catalyst achieves a 6-fold increase, and the CO selectivity is 83.0%. This research provides new insights into the CO 2 reduction pathway in mild conditions and emphasizes the importance of the adsorption–activation tandem process for enhancing photoactivity and selectivity.