Polyimide/Ag2WO4 Z-Scheme Heterojunction for Efficient Photocatalytic Degradation of Tetracycline

It is of great significance to construct a Z-scheme heterojunction for improving solar light harvesting and achieving efficient separation of photogenerated carriers and then enhancement of the photocatalytic performance of semiconductor photocatalysts. Herein, the direct Z-scheme PI/Ag2WO4 heterojunction was designed and prepared according to the band edge potentials of the semiconductor. Due to the fact that the Z-scheme structure not only endowed the PI/Ag2WO4 composites with efficient separation of photogenerated electron-hole pairs but also reserved the redox ability of the valence band and conduction band of monophase catalysts, the 50% PI/Ag2WO4 heterojunction exhibited excellent photocatalytic activity, which were 2.9 and 1.5 times those of the PI and Ag2WO4 photocatalysts, respectively. The photocatalytic reaction mechanism of PI/Ag2WO4 composites was confirmed by the results of TEM, UV-vis, XPS, and EPR experiments. This work provides a feasible strategy to design high-performance photocatalysts in the field of practice purification of wastewater.

Redox-active polyimides for energy conversion and storage: from synthesis to application

As the demand for next-generation electronics is increasing, organic and polymer-based semiconductors are in the spotlight as suitable materials owing to their tailorable structures along with flexible properties. Especially, polyimide (PI) has been widely utilised in electronics because of its outstanding mechanical and thermal properties and chemical resistance originating from its crystallinity, conjugated structure and π-π interactions. PI has recently been receiving more attention in the energy storage and conversion fields due to its unique redox activity and charge transfer complex structure. In this review, we focus on the design of PI structures with improved electrochemical and photocatalytic activities for use as redox-active materials in photo- and electrocatalysts, batteries and supercapacitors. We anticipate that this review will offer insight into the utilisation of redox-active PI-based polymeric materials for the development of future electronics.

Fabrication of novel organic/inorganic polyimide-BiPO4 heterojunction for enhanced photocatalytic degradation performance

The organic-inorganic heterojunction composites possessed excellent physical and chemistry properties has enormous potential in the field of wastewater purification. Herein, the novel PI-BiPO₄ heterojunction photocatalysts were synthesized via facile hydrothermal method. The different ratio PI-BiPO₄ composites exhibited remarkable photodegradation performance than that of the pure BiPO₄. The enhanced photocatalytic activity of 75PI-BiPO₄ composites was ascribed to the improvement of light absorption ability and larger specific surface area. What is more, the forming of heterojunction between PI and BiPO₄ was conduce to the separation and migration of the photogenerated electron-hole pairs. The h⁺ and O₂^- confirmed by EPR facility were predominant reactive species in the photocatalytic process. In addition, the feasible pathway of photocatalytic degradation TC were inferred on account of the UPLC-MS/MS results. This work provides a novel organic-inorganic heterojunction composites for supporting the field of the pollutant purification.