Boosting photothermal-assisted photocatalytic H2 production over black g-C3N4 nanosheet photocatalyst via incorporation with carbon dots.

Although photocatalytic H2 production based on semiconductor materials has a wide potential application, it still facing challenges such as slow reaction kinetics or complex synthesis processes. To meet these challenges, the carbon dots loaded black g-C3N4 (CN-B-CDs) was synthesized by simple calcination method to achieve efficient photothermal-assisted photocatalytic H2 production. Photothermal imaging experiments confirmed the photothermal effect of CN-B and CDs as dual heat sources to increase the temperature of the composite system, thus improving the effective separation of photo-generated charges. In addition, multiple photocatalytic H2 production tests exhibited that CN-B-CDs photocatalysts not only have strong stability but also can accommodate a variety of complex water bodies, which displayed the potential for industrial application. This study combined the photothermal effect and the mechanism by which the CDs promote the charge transfer to design a new photocatalytic H2 production system and provided a new scheme for achieving efficient photothermal-assisted photocatalytic H2 production using carbon-based materials.

Plasmonic coupling-boosted photothermal composite photocatalyst for achieving near-infrared photocatalytic hydrogen production.

The development of photocatalysts that effectively utilize low-energy photons for efficient photocatalysis still faces a number of challenges. Herein, an efficient NIR-driven system based on WO3-x/ZnIn2S4 (WO3-x/ZIS) prepared by a simple low-temperature water-bath method, and the optimal WO3-x/ZIS-3 composites can reach a hydrogen-production efficiency of 14.05 µmol g-1h-1 under NIR light irradiation. The localized surface plasmon (LSPR) resonance effect in WO3-x quantum dots (QDs) not only broadens the ZIS photo-response range, but also the photothermal effect of WO3-x can increase the local reaction temperature of WO3-x/ZIS composite system, thus enhancing the photothermal-assisted photocatalytic activity. In addition, density functional theory (DFT) calculations show that the difference in work function between WO3-x and ZIS can lead to the formation of interfacial electric field (IEF), which not only promotes the separation and migration efficiency of photogenerated carriers, but also facilitates the photocatalytic water splitting for hydrogen production. This study provides possible directions for the construction of NIR-driven photothermal-assisted photocatalytic hydrogen production system.

Plasmonic coupling-boosted photothermal nanoreactor for efficient solar light-driven photocatalytic water splitting.

Photothermal nanoreactor with rapid charge transfer and improved spectral utilization is a key point in photocatalysis research. Herein, silver sulfide quantum dots (Ag2S QDs) were coating on the surface of porous graphitic carbon nitride nano vesicles (PCNNVs) to form Ag2S/PCNNVs nanoreactors by a simple calcination method for obtaining efficient photothermal-assisted photocatalytic hydrogen (H2) evolution under simulated/real sunlight irradiation. In particularly, the as-prepared optimal 3% Ag2S/PCNNVs sample exhibited the H2 production rate of 34.8 mmol h-1 g-1, which was 3.5 times higher than that of bare PCNNVs. The enhancement of photothermal-assisted activity over the Ag2S/PCNNVs composite system is mainly attributed to the coupling of the photothermal conversion performance of Ag2S QDs and the thermal insulation performance of PCNNVs based on the plasmonic coupling-boosted photothermal nanoreactor. This study presents a promising strategy for the development of high-efficient photothermal-assisted photocatalysts.

Photocatalytic Self-Fenton System of g-C3N4-Based for Degradation of Emerging Contaminants: A Review of Advances and Prospects.

The discharge of emerging pollutants in the industrial process poses a severe threat to the ecological environment and human health. Photocatalytic self-Fenton technology combines the advantages of photocatalysis and Fenton oxidation technology through the in situ generation of hydrogen peroxide (H2O2) and interaction with iron (Fe) ions to generate a large number of strong reactive oxygen species (ROS) to effectively degrade pollutants in the environment. Graphite carbon nitride (g-C3N4) is considered as the most potential photocatalytic oxygen reduction reaction (ORR) photocatalyst for H2O2 production due to its excellent chemical/thermal stability, unique electronic structure, easy manufacturing, and moderate band gap (2.70 eV). Hence, in this review, we briefly introduce the advantages of the photocatalytic self-Fenton and its degradation mechanisms. In addition, the modification strategy of the g-C3N4-based photocatalytic self-Fenton system and related applications in environmental remediation are fully discussed and summarized in detail. Finally, the prospects and challenges of the g-C3N4-based photocatalytic self-Fenton system are discussed. We believe that this review can promote the construction of novel and efficient photocatalytic self-Fenton systems as well as further application in environmental remediation and other research fields.

Construction of S-Scheme 2D/2D Crystalline Carbon Nitride/BiOIO3 van der Waals Heterojunction for Boosted Photocatalytic Degradation of Antibiotics.

Utilization of semiconductor photocatalyst materials to degrade pollutants for addressing environmental pollution problems has become a research focus in recent years. In this work, a 2D/2D S-scheme crystalline carbon nitride (CCN)/BiOIO3 (BOI) van der Waals heterojunction was successfully constructed for effectively enhancing the degradation efficiency of antibiotic contaminant. The as-synthesized optimal CCN/BOI-3 sample exhibited the highest efficiency of 80% for the photo-degradation of tetracycline (TC, 20 mg/L) after 120 min visible light irradiation, which was significantly higher than that of pure CCN and BOI. The significant improvement in photocatalytic performance is mainly attributed to two aspects: (i) the 2D/2D van der Waals heterojunction can accelerate interface carriers' separation and transfer and afford sufficient active sites; (ii) the S-scheme heterojunction elevated the redox capacity of CCN/BOI, thus providing a driving force for the degradation reaction. The degradation pathways of TC for the CCN/BOI composite were investigated in detail by liquid chromatography-mass spectrometry (LC-MS) analysis. This work provides a design idea for the development of efficient photocatalysts based on the 2D/2D S-scheme van der Waals heterojunctions.