Vacancy-rich layered materials with good electron-transfer property are of great interest. Herein, a full-spectrum responsive vacancy-rich monolayer BiO has been synthesized. The increased density of states at the conduction band (CB) minimum in the monolayer BiO is responsible for the enhanced photon response and photo-absorption, which were confirmed by UV/Vis-NIR diffuse reflectance spectra (DRS) and photocurrent measurements. Compared to bulk BiO , monolayer BiO has exhibited enhanced photocatalytic performance for rhodamine B and phenol removal under UV, visible, and near-infrared light (NIR) irradiation, which can be attributed to the vacancy V ''' as confirmed by the positron annihilation spectra. The presence of V ''' defects in monolayer BiO promoted the separation of electrons and holes. This finding provides an atomic level understanding for developing highly efficient UV, visible, and NIR light responsive photocatalysts.

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Natural photosynthesis is a solar light-driven process utilized by plants to convert CO 2 and water into carbohydrate molecules. The goal of artificial photosynthesis is the reduction of CO 2 directly from air into high purity value-added products at atmospheric pressure. However, its realization, combined with deep mechanism investigation, is a huge challenge. Herein, we demonstrate that hexagonal tungsten bronze M 0.33 WO 3 (M = K, Rb, Cs) series with {010} facets, prepared by a peculiar "water-controllable releasing" solvothermal method, showed excellent full spectrum (UV, visible, and NIR lights)-induced photocatalytic CO 2 reduction performance directly from the air at ambient pressure. Particularly, after 4 h near-infrared light irradiation, ca. 4.32% CO 2 in the air could be converted into CH 3 OH with 98.35% selectivity for Rb 0.33 WO 3 . The experiments and theoretical calculations unveiled that the introduced alkali metal atom occupied the tunnel of hexagonal structure and donated more free electrons to reconstruct the electronic structure of M 0.33 WO 3 , which can enhance the polaron transition, modify the energy band structure, selectively adsorb CO 2 rather than O 2 from the air, decrease the activation energy of CO 2 reaction, and finally make the effective CO 2 reduction in the air a reality. This work may provide a new possibility for the practical application of artificial photosynthesis.

An efficient Fe(2)O(3)-pillared rectorite (Fe-R) clay was successfully developed as a heterogeneous catalyst for photo-Fenton degradation of organic contaminants. X-ray diffraction analysis and high-resolution transmission electron microscope analysis clearly showed the existence of the Fe(2)O(3) nanoparticles in the Fe-R catalyst. The catalytic activity of the Fe-R catalyst was evaluated by the discoloration and chemical oxygen demand (COD) removal of an azo-dye rhodamine B (RhB, 100 mg/L) and a typical persistent organic pollutant 4-nitrophenol (4-NP, 50 mg/L) in the presence of hydrogen peroxide (H(2)O(2)) under visible light irradiation (lambda > 420 nm). It was found that the discoloration rate of the two contaminants was over 99.3%, and the COD removal rate of the two contaminants was over 87.0%. The Fe-R catalyst showed strong adsorbability for the RhB in the aqueous solution. Moreover, the Fe-R catalyst still showed good stability for the degradation of RhB after five recycles. Zeta potential and Fourier transform infrared spectroscopy were used to examine the photoreaction processes. Finally, a possible photocatalytic mechanism was proposed.