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.

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

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

The availability of robust, versatile, and efficient photocatalysts is the main bottleneck in practical applications of photocatalytic degradation of organic pollutants. Herein, N‐WO3/Ce2S3 nanotube bundles (NBs) are synthesized and successfully immobilized on a carbon textile, resulting in a flexible and conducting photocatalyst. Due to the large interfacial area between N‐WO3 and Ce2S3, the interwoven 3D carbon architecture and, more importantly, the establishment of a heterojunction between N‐WO3 and Ce2S3, the resultant photocatalyst exhibits excellent light absorption capacity and superior ability to separate photoinduced electron–hole pairs for the photocatalytic degradation of organic compounds in air and water media. Theoretical calculations confirm that the strong electronic interaction between N‐WO3 and Ce2S3 can be beneficial to the enhancement of the charge carrier transfer dynamics of the as‐prepared photocatalyst. This work provides a new protocol for constructing efficient flexible photocatalysts for application in environmental remediation.

Heterojunction Architecture of N-Doped WO3 Nanobundles with Ce2S3 Nanodots Hybridized on a Carbon Textile Enables a Highly Efficient Flexible Photocatalyst

Synthesis of C-In2O3/BiOI composite and its enhanced photocatalytic degradation for methyl blue

The invention discloses a method for preparing a bismuth oxyhalide photocatalyst and relates to the technical field of chemistry. The method is used for solving the problems existing in the conventional method for preparing bismuth oxyhalide that the method is complicated, recovery is difficult and environmental pollution is easily caused. The method comprises the following steps: adding a mixed electroplating solution of a bismuth salt, Na2EDTA (Ethylene Diamine Tetraacetic Acid Disodium) and sucrose into a two-electrode system according to a molar ratio, wherein the two-electrode system comprises an anode made of FTO conducting glass, controlling the electroplating solution to be at a first set temperature, and electroplating to obtain elemental bismuth by a constant potential rectifierunder the conditions of set current and first set time; pouring electrolyte taking halides as raw materials into the two-electrode system, taking the FTO conducting glass plated with the elemental bismuth as the anode, controlling the electrolyte to be at a second set temperature, and carrying out an anodic oxidation reaction under the conditions of a set voltage and second set time, thereby obtaining the BiOI.

Hong Liu

Papers

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

Heterojunction Architecture of N-Doped WO3 Nanobundles with Ce2S3 Nanodots Hybridized on a Carbon Textile Enables a Highly Efficient Flexible Photocatalyst

Synthesis of C-In2O3/BiOI composite and its enhanced photocatalytic degradation for methyl blue

Method for preparing bismuth oxyhalide photocatalyst