Photocatalytic Degradation of 4-Nitro Phenol in Aqueous Solution by the AgInS2 Nanoparticles Synthesized via Microwave Heating Technique

With increasing demands for environmental protection, photocatalysis has attracted great attention, and AgInS2 based photocatalysis are an attractive system to study.
In this work, AgInS2 (AIS) nanoparticles were synthesized via the microwave heating process with the power of 900 W for 5 min, which showed excellent photocatalytic activities upon the degradation of 4-nitro phenol (4-NP) under visible light irradiation.
The optimum catalyst showed the removal efficiency up to 97%, of 4-NP with the 15 mg L−1 concentration from the water after 80 min photocatalytic reaction time. The mechanism of photocatalysis was also analyzed. The product was characterized by PXRD, FE-SEM, TEM, and UV-Vis spectroscopy. A scanning electron microscope and transmission electron microscope revealed the particle morphology, with the average size of 70 nm. Powder X-ray diffraction confirmed that the resultant product is a pure orthorhombic phase of AIS nanoparticles. The band gap energy of 1.96 eV estimated by the diffuse reflectance spectroscopy (DRS), exhibited that this product can be prone for photocatalytic activity in the visible region.
It is suggested that the AgInS2 nanoparticles developed in our work can provide a new platform for the design of highly efficient photocatalysts under visible light irradiation.