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The effective utilization of the local surface plasmon resonance (LSPR) effect of metal nanoparticles to improve optical absorption capacity and inject hot electrons into photocatalysts opens up new directions and ideas to solve the problem of solar energy utilization efficiency of photocatalysts. In this study, we created an in situ technique for preparing plasmon Ag nanoparticles (NPs) decorated with a covalent organic framework (COF), named Ag/TpPa-1-COF. The LSPR effect of Ag NPs results in an outstanding rate of H2 production that is 801.4 μmol g−1 h−1 for the 3% Ag/TpPa-1 photocatalyst, which is almost 4 times as effective as that of the unmodified TpPa-1-COF. Moreover, finite-difference time-domain (FDTD) simulation results reveal that the strongest electric field intensity is presented when the catalyst is excited at λ = 465 nm. Furthermore, plasmonic "hot spots" induced by the interfacial electric field enhancement factor distribution of Ag/TpPa-1 were simulated in detail by adjusting the number, particle size, and gap distance of Ag NPs. Additionally, density functional theory (DFT) calculations show that electron transfer from Ag NPs to TpPa-1 occurs at the Ag/TpPa-1 interface, and N sites in Ag/TpPa-1 exhibit low Gibbs free energy (ΔGH*) for enhanced photocatalytic H2 evolution. Overall, this research provides new insights into the plasmonic "hot spot" region that performs effectively for hydrogen evolution. [ABSTRACT FROM AUTHOR]

A dispersion containing black TiO2 photocatalyst was prepared and sprayed onto the concrete's surface to achieve a black TiO2-based photocatalytic concrete paving eco-block, and its photocatalytic NO removal ratio is approximately 1.7 times as high as that of a white TiO2-based eco-block, resulting from the enhanced optical absorption intensity, abundant oxygen vacancies, and highly produced superoxide anion radicals (˙O2−) of black TiO2. Moreover, the black TiO2-based concrete paving eco-block exhibits significantly enhanced compressive strength and abrasion resistance when using water-glass as a binder, which could satisfy the demand for practical application. Furthermore, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was performed to dynamically track the reactive products and intermediates across the surface of the B-TiO2 photocatalyst in a time sequence to investigate the reaction mechanism. It has been demonstrated that almost no harmful by-products were produced when NO was removed via photocatalysis, and the applicability of the as-prepared eco-blocks was evaluated considering the effects of various reaction conditions. Additionally, a computational fluid dynamics (CFD) model for solar-driven photocatalytic abatement of atmospheric NO in a realistic urban street coating with black TiO2-based photocatalytic concrete paving eco-blocks was constructed and simulated to assess the real-world applicability of the developed approach. Overall, this research may offer fresh perspectives on how to create ecologically acceptable photocatalytic products for the removal of air pollutants using solar light. [ABSTRACT FROM AUTHOR]

In this study, Pt-M/WO3 (M = Cu, Co, and Ni) thin films are effectively synthesized by preparing homogeneous precursor sols, spin-coating, toluene-etching, and calcination. Furthermore, the microstructural, chemical, and electrochemical properties of the WO3, Pt-Cu/WO3, Pt-Co/WO3, and Pt-Ni/WO3 thin films are also systematically compared. The results demonstrate that when compared to the WO3 thin film, the photocatalytic capability for methylene blue (MB) solution degradation is greatly increased in the Pt-M/WO3 thin films. Transfer routes for photogenerated charges and an improved photocatalytic process are suggested based on the experimental results. Due to the large difference in the work function (Φ) between the bimetallic alloy Pt-M and WO3, a bending of the energy bands at the Pt-M/WO3 interface is presented. Furthermore, the introduction of transition metals such as Cu, Co, or Ni modifies the electronic structure of Pt-M/WO3 thin films, facilitating the separation and migration of electrons and holes. Specifically, the photogenerated electrons migrate from the CB of WO3 to Pt-Co or Pt-Ni nanoparticles in the samples of Pt-Co/WO3 or Pt-Ni/WO3 thin films, while the hot electrons from the localized surface plasmon resonance (LSPR) effect of Cu could transfer to the conduction band (CB) of WO3 and other electrons generated from the photoexcitation of the WO3 semiconductor itself in the sample of the Pt-Cu/WO3 thin film. In summary, this work proposes a unique strategy for creating electron regulation in Pt-M decorated WO3 thin films for photocatalytic application. [ABSTRACT FROM AUTHOR]