Microwave assisted synthesis of PQ-GDY@NH2-UIO-66(Zr) for improved photocatalytic removal of NO under visible light

Pyrazinoquinoxaline-based graphdiyne (PQ-GDY) contains a fixed number of sp−sp2 hybridized carbon atoms and pyrazine-like sp2 hybridized N atoms. In this paper, NH2-UIO-66(Zr) on PQ-GDY substrate was successfully constructed with the help of microwave-assisted heating. PQ-GDY surface acts as a microwave antenna under microwave irradiation to rapidly absorb microwave energy and form hot spots (hot spot effect), which facilitates the formation of well-dispersed NH2-UIO-66(Zr) with good crystallinity. Transient absorption spectra show that high hole transport property of PQ-GDY can accelerate the migration of photogenerated holes from NH2-UIO-66(Zr) to PQ-GDY and greatly reduce the recombination rate of photogenerated electrons and holes due to the strong interaction between PQ-GDY and NH2-UIO-66(Zr). Under visible light (λ ≥ 420 nm), [email protected]2-UIO-66(Zr) shows high photocatalytic stability and high NOx removal rate up to 74%, which is 44% higher than that of primitive NH2-UIO-66(Zr). At the same time, it inhibits the formation of toxic by-products (NO2) and limits its concentration to a low level.