In the grant proposal, I focus on the development of novel photocatalysts to convert solar energy into chemicals and fuels, mainly including photocatalytic CO2 reduction into CO fuel and organic synthesis. Different photocatalysts such as twin-Au modified TiO2, and metal Pd cube decorated perovskites are designed to achieve this goal. The following text introduces some typic examples about the addressed issue in scientific area and shows how we can obtain higher and better solar to energy conversion efficiency.
The efficient utilization of sunlight to activate CO2 provides a renewable route to offset CO2 emissions and support a more sustainable global carbon cycle. More importantly, the direct photoreduction of CO2 into CO, rather than CH4, is arguably the technologically and economically preferred approach. In the grant proposal, I reported a strategy for depositing phase-modified Au nanoparticles abundant with stable twinned crystal planes as a co-catalyst on TiO2 for the effective photocatalytic reduction of CO2 to CO. Compared to pristine TiO2, the addition of twinned Au nanoparticles raise photocatalytic CO production activity by nearly 40-fold and establishes near unity CO selectivity (99%). (Angewandte Chemie - International Edition, 2022, 10.1002/anie.202204563)
The Suzuki coupling reaction is one of the most important organic synthetic methods for C–C bond formation. Recent research has shown the possibility to enhance the Suzuki coupling reaction under light irradiation through the use of photocatalytic supports in combination with Pd NPs. Yet, the temperature-dependent photocatalytic activity of Pd-photocatalytic support hybrids is seldom investigated. Therefore, I try to introducte Pd cube onto perovskite to synthesize highly efficient photocatalyst for organic transformation.The Pd/CsPbBr3 catalyst exhibits 11 times higher activity than pure CsPbBr3 at 30 °C due to reduced activation barrier and facilitated charge carrier dynamics. This work has been published: ACS Applied Materials & Interfaces 2022, 14, 15, 17185–17194.
Recently, metal halide perovskites (MHPs) have emerged as efficient H2 evolution photocatalysts. However, most of the H2 evolution reaction (HER) experiments are performed in saturated aqueous hydrohalic acid HX (X = Br and I) solutions. Based on the above work, I have prepared crystalline-amorphous core@shell Pd (APd) cube decorated Cs3Bi2Br9 photocatalyst, to further improve the photocatalytic performance of H2 evolution coupled with organic synthesis. Such a dual-purpose photocatalytic reaction offers an excellent alternative for H2 evolution over MHP photocatalysts avoiding concentrated hydrohalic acid solutions. As a result, the optimized APd/Cs3Bi2Br9 photocatalyst exhibits over 4-fold higher photoactivity that the pure Cs3Bi2Br9 counterpart toward H2 and benzaldehyde production.
Photocatalytic conversion of light to the chemical fuel appears to be an ideal green approach and the above mentioned works clearly exhibit how to improve the photocatalytic performance towards solar to energy conversion, i.e. engineering the phase, morphology and structure of cocatalysts.
