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Photocatalytic H2O2 generation is compelling for sustainable solar-to-chemical conversion, but it is an emerging challenge to realize efficient conversion without the consumption of any alcohols. Also, the in-depth mechanism for the structure-induced activity enhancement is still unclear but remains pivotal for practical application. Herein, cyano groups and S atoms were collectively introduced into carbon nitride (MTCN), and the vital roles and detailed mechanism were investigated. Specifically, MTCN exhibited a laudable H2O2 generation of 68.12 mM gcat−1 h−1, together with an apparent quantum yield of 49.01% at 420 nm. Intriguingly, it was observed that the existence of some contaminants can promote H2O2 generation and, in turn, accelerate degradation. Additionally, it is revealed that the S atoms and cyano group could facilitate oxygen adsorption and H+ adsorption, respectively. This study shows a promising strategy to construct modified g-C3N4 and exhibits a clear mechanism for H2O2 generation paired with simultaneous contaminant treatment. [ABSTRACT FROM AUTHOR]

Catalytic hydrogen peroxide (H2O2) generation from oxygen and water enables a sustainable environment to operate in an effective and green energy‐to‐chemical conversion way, which has attracted increasing interest in the fields of energy production and environment treatment. In light of this, tremendous progresses and developments have been made during the past decades in catalytic H2O2 production for pollutant removal from three perspectives including photocatalysis, electrocatalysis or chemical activation. Herein, we critically review the state‐of‐the‐art developments over various procedures of H2O2 generation and its further application, with the existence of photocatalysts, electrocatalysts, and catalysts, respectively. Benefiting from extensively experimental and theoretical investigations, the performance and stability of H2O2 generation and its utilization can be maneuvered by devising catalytic platform based on numerous catalysts with predominant electronic, chemical and physical properties, which endow the catalysts with efficient electrons transportation, abundant active sites, and sufficient oxygen adsorption for H2O2 generation. Furthermore, this review also discusses the formation mechanism of H2O2 by 2e‐ORR and 2e‐WOR, as well as its functional process of activating and removing pollutants, and summarizes the design principles of various catalysts by focusing on the formation of H2O2. We finally highlight the specific challenges and prospects related to the utilization of catalysts and envision the possible future development trends in the fields of pollutant removal. [ABSTRACT FROM AUTHOR]

Semiconductor supported noble metal nanoparticles are widely used in H2 evolution. Due to the high cost and low catalytic efficiency of noble metals, single‐atom catalysts (SACs) are considered as very potential materials to overcome these shortcomings. Herein, the construction of the ZnO–ZnS heterojunction with an excess amount of Zn vacancies promotes the separation of charge carriers and improves the utilization of electrons. Meanwhile, the zinc vacancies on ZnS provide effective anchor sites for Pt atoms, which is beneficial to obtain highly dispersed single Pt atoms catalyst (ZOS‐SAPt). Due to the formation of an intermediate energy level by zinc vacancies, the introduction of Pt single atoms promotes the novel type‐V electron transport from the conduction band of ZnO to the intermediate energy level and then to the Pt atom. The type‐V electron transport not only retains the high reduction potential of photogenerated electrons, but also avoids the loss of carriers. The resultant ZOS‐SAPt shows outstanding photocatalytic performance for H2 evolution under simulated sunlight, reaching 9.6 mmol g−1 h−1, which is 201 times that of ZnO–ZnS. These results provide important information for further development of photocatalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting for hydrogen (H2) generation is a potential strategy to solve the problem of energy crisis and environmental deterioration. However, powder-like photocatalysts are difficult to recycle, and the agglomeration of particles would affect the photocatalytic activity. Herein, a direct Z-scheme CdS/WO3 composite photocatalyst was fabricated based on carbon cloth through a two-step process. With the support of carbon cloth, photocatalysts tend to grow uniformly for further applications. The experimental results showed that the H2 yield of adding one piece of CdS/WO3 composite material was 17.28 μmol/h, which was 5.5 times as compared to that of pure CdS-loaded carbon cloth material. A cycle experiment was conducted to verify the stability of the as-prepared material and the result demonstrated that the H2 generation performance of CdS/WO3 decreased slightly after 3 cycles. This work provides new ideas for the development of recyclable photocatalysts and has a positive significance for practical applications. [ABSTRACT FROM AUTHOR]