Nanostructured Metal Sulfides: Classification, Modification Strategy, and Solar‐Driven CO 2 Reduction Application

Creatively constructing Z-scheme composites is a promising and common strategy for designing effective photocatalyst systems. Herein, we synthesized Z-scheme Fe2O3@Ag-ZnO@C heterostructures from the Fe-MOFs and applied it to photodegradation of tetracycline and methylene blue pollutants in wastewater. The optimized sample exhibits a remarkable performance as well as stability under visible light irradiation. The calculating and experimental results demonstrate that the Fe2O3@ZnO nanointerface and carbon sheath together boost the transfer efficiency of photogenerated carriers and absorption ability, thereby improving the photocatalytic activity. Furthermore, detailed mechanism investigation reveals the pivotal role of reactive oxygen species (•OH and •O2-) generated, resulting in remarkable performance. In addition, cell biology experiments reveal that the wastewater after photocatalytic treatment has good biological compatibility, which is important for applications. This work provides valuable information for constructing high-performance Z-scheme photocatalysts from MOFs for environmental treatment.

Constructing Fe-MOF-Derived Z-Scheme Photocatalysts with Enhanced Charge Transport: Nanointerface and Carbon Sheath Synergistic Effect

Amorphous type FeOOH modified defective BiVO4 photoanodes for photoelectrochemical water oxidation

Carbon deposit during the catalytic oxidation of volatile organic compounds (VOCs) is a key factor to restrict long-term stability of catalysts. Herein, a modified ordered porous catalyst with high coke-resistance performance was developed by introducing oxygen vacancies (OVs) into CeO2 through simple redox and steam treatment (ARCeO2), and applied in efficiently photothermocatalytic degradation of VOCs. Abundant OVs in ARCeO2 leads to enhanced light absorption, improved charge separation and increased reactive oxygen generation, and then promote its photothermocatalytic performance. Moreover, no obvious decrease was observed in the photothermocatalytic activity of ARCeO2 at 200 °C for 25 h reaction. Its superior photothermocatalytic stability can be attributed to the less intermediates and limited coke accumulation onto ARCeO2. This work provides a facile and cost-effective strategy for the design and fabrication of CeO2 catalyst with strong coke-resistance potential and highlights the significance of OVs engineering for improving the photothermocatalytic performance of VOCs degradation.

Introduce oxygen vacancies into CeO2 catalyst for enhanced coke resistance during photothermocatalytic oxidation of typical VOCs

Designing and constructing effective and stable photocatalysts is the major challenge in the development of photocatalysis. Herein, we demonstrate a conceptual strategy to effectively improve the charge separation in a ternary material system (CeO2/C/SnS2), by introducing ultrathin carbon layer between CeO2 nanorods and SnS2 particles as a conductive electron transport “highway”. Such ternary CeO2/C/SnS2 gives rise to a largely enhanced photocatalytic removal performance of phenol (100%, 60 min), comparing with CeO2/SnS2 (50%) and CeO2 (20%). Experimental results reveal that carbon layer acts as a high work function, superior electron mobility accepts and enables a fast transportation, accelerating the photocatalytic degradation performance of phenol. Our design introduces material components to provide a dedicated charge-transport pathway, conquering the materials’ intrinsic properties, providing a new perspective for water purity.

An ultrathin carbon layer activated CeO2 heterojunction nanorods for photocatalytic degradation of organic pollutants

Oxygen vacancy plays an important role in many fields, such as photocatalysis, energy storages, electro-catalysis, which has been widely investigated both by experiment and theoretical calculations. Herein, this review presents the new type and advanced methods to detect the existence of oxygen vacancies in nanomaterials, such as, electron paramagnetic resonance, synchrotron radiation-based X-ray absorption fine structure, X-ray photoelectron spectroscopy and positron annihilation spectroscopy measurements. In addition, we provide some perspectives on the challenge and new direction for future research in oxygen vacancy. We hope that this minireview can offer some useful contributions to the future development of defective nanomaterials for diverse application.

Nan Ni

Papers

An overview of advanced methods for the characterization of oxygen vacancies in materials