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The photocatalytic CO2 reduction reaction (CRR) holds great promise for curbing anthropogenic CO2 emissions, though boosting photocatalyst activity and tuning product selectivity remain key priorities. Herein, isolated Ni single atoms dispersed on defect rich zirconia (Ni‐SA‐x/ZrO2) are identified as a very promising photocatalyst for CRR under Xe lamp irradiation, showing good activity and CO selectivity in the absence of added sacrificial agents or sensitizers. Due to an abundance of accessible nickel single atomic sites, the optimized photocatalyst affords CO at a rate of 11.8 µmol g−1 h−1 (92.5% selectivity). Experimental and theoretical investigations determine that the atomically dispersed Ni sites lower the energy barrier for CO2 to CO conversion via an adsorbed COOH intermediate, while also suppressing H2 desorption in the competing water splitting reaction. The Ni single atom sites thus simultaneously promote CO2 conversion and CO selectivity, thus offering valuable new insights for the future design of improved metal single‐atom catalysts for CRR. [ABSTRACT FROM AUTHOR]

We herein demonstrate the uniform porous hierarchical plate-like BiOCl/2D networks Bi 2 S 3 heterostructures realized by a facile two-step hydrothermal technique. The synthesis involved an anion exchange process by reacting pre-synthesized BiOCl irregular octagonal nanoplates with Na 2 S 2 O 3 ·5H 2 O in an aqueous solution. The experiment results revealed that the 3D plate-like heterostructures were composed of internal BiOCl and outside networks interwoven by 1D Bi 2 S 3 nanorods. Interestingly, the heterostructures had almost the same thickness and the bigger length compared to the precursor BiOCl. We proposed the possible formation mechanism of the composites which involved selective ion-exchange reaction, the following Ostwald ripening process and epitaxial growth. And the crystal lattice matching between the a- or b-axis of tetragonal BiOCl (a = b = 3.89 Å) and the a-axis of orthorhombic Bi 2 S 3 (a = 3.981 Å) could be responsible for the in-situ topotactic transformation. Due to the formation of hetero-nanostructures, the unique spatial architecture features and the existence of oxygen vacancies, the BiOCl/Bi 2 S 3 composites exhibited significantly extended photo-responsive range and improved photocatalytic activity for reduction of Cr VI under visible-light irradiation. Moreover, the possible mechanism of photocatalysis process was investigated. Our work is expected to inspire further attempts for hierarchical and unconventional hetero-nanostructures with unique spatial architecture, which is very promising for photocatalysis and other applications. [ABSTRACT FROM AUTHOR]

A series of BiOBr nanosheets with tunable exposing proportion of (0 1 0) facets had been synthesized. In the synthesis process, different n -alcohols are used, which not only promote the exposure of (0 1 0) facets, but also modulate the size and thickness of these BiOBr nanosheets in a wide range. Furthermore, these nanosheets showed an efficient photodegradation activity for salicylic acid (SA) and Rhodamine B (RhB). By comparison, the sample prepared in n -hexanol possessed the highest photocatalytic activity than those synthesized in n -butanol and methanol, respectively. This excellent photocatalytic activity was attributed to the thin lamellar thickness and the exposure of (0 1 0) facets, which facilitated the separation of photoinduced electrons and holes. [ABSTRACT FROM AUTHOR]

• Photocatalytic bacteria inactivation over air-water-catalyst triphase systems. • Direct observation of wettability-controlled interface structures. • 18 times higher H 2 O 2 generation rate than the corresponding diphase system. • Two orders of magnitude reduced colony concentration within 30 min irradiation. • Applicable in the antibacterial of atmosphere-connected water bodies. Antibacterial technology based on photo-generated reactive oxygen species (ROS) represents a promising strategy for antibiotic-resistant bacteria inactivation, but often results in poor activity due to the limited O 2 solubility in traditional water-catalyst diphase system. In this work, we develop an air-water-catalyst triphase system to explore the superiority of air phase-supplied O 2 for the enhancement of ROS generation and Klebsiella pneumoniae (KPN) inactivation efficiencies. Using P25-TiO 2 as model photocatalysts, we demonstrate that Wenzel-Cassie coexistent wetting state is the most conducive for photocatalytic ROS generation, offering a H 2 O 2 generation rate of 1003 ± 52 μM h−1, which is 18 times higher than corresponding diphase system. It also affords an over two orders of magnitude reduced KPN colony concentration within 30 min irradiation, achieving over 99 % light-triggered removal efficiency. The advantages of triphase system for photocatalytic bacterial inactivation will inspire the development of efficient photocatalytic antibacterial systems in atmosphere-connected water bodies. [ABSTRACT FROM AUTHOR]

Quantum-sized BiOCl in the cage-like pores of SBA-16 have been prepared by impregnation method. The average diameter of BiOCl obviously decreases to 6.1 nm due to the confinement effect from the framework of SBA-16. Compared to the bulk BiOCl, the quantum-sized BiOCl in the cage-like pores of SBA-16 possesses a larger bandgap (3.35 eV), and the quantum confinement effect simultaneously result in an elevated electron transport ability and enhanced redox ability of charge carriers. The as-prepared BiOCl@SBA-16 photocatalysts exhibit high activity toward degradation of methyl orange (MO) under simulated sunlight irradiation. [ABSTRACT FROM AUTHOR]

Construction of heterogeneous transmission interfaces that spatially separate Coulomb-bound electron-hole pairs in semiconductors allows exceptional control over optoelectronic properties, thereby enhancing the efficiency of solar energy conversion. In this study, we propose an effective photocatalyst for full water splitting named MS/BOC-x/Pd, comprising atomic layer of MoS 2 bonded to defect-rich BiOCl, and a non-plasmonic Pd oxidation co-catalyst is exclusively assembled on the sides to form a strong electronic coupling and maximize the trapping of holes. The presence of the Mo-S-Bi motif promotes rapid charge migration, resulting in impressive rates of H 2 and O 2 formation (165 and 9.17 μmol g−1 h−1, respectively), without the requirement of sacrificial agents or sensitizers. Through experimental and theoretical investigations, we discovered that the occupation of sulfur atoms in oxygen vacancies extends the overlap of surface charges, thereby facilitating the separation of inner/interfacial electron-hole pairs. The Mo-S-Bi bond provides directional guidance for charge transfer to the surface redox sites. These findings provide valuable insights for the future design of highly efficient photocatalysts for solar energy conversions. [Display omitted] • MS/BOC-Pd photocatalysts with well-designed charge transport channels were successfully constructed. • The atomic-level migration pathway(s) pertinent to water splitting have been systematically elucidated. • DFT calculations confirmed that the Mo-S-Bi configuration is optimal for charge migration. • Improved performance of photochemical conversion properties. [ABSTRACT FROM AUTHOR]