Photochemical modification of tea waste by tungsten oxide nanoparticle as a novel, low-cost and green photocatalyst for degradation of dye pollutant.

So far, many adsorbents and nanocomposites have been synthesized by different methods and used to remove or degradation of dye pollutants. Nowadays, the use of natural adsorbents and their modification with simple methods based on metal oxides are of interest to many researchers. In this study, for the first time, we report the simple and low-cost modification of tea pomace waste (TPW) with tungsten oxide (WO3) based on the photochemical method as a green, cost-effective, and biodegradable photocatalyst for the degradation of Rh B dye pollutant. The results obtained from FE-SEM, EDAX, XRD, XPS, PL, BET and UV-Vis Diffusive Reflectance (DRS) analyses confirmed the successful modification of the TPW surface with WO3 (WO3/TPW). The parameters affecting the photocatalytic behavior of WO3/TPW, including the time of photochemical modification and the type of radiation on its photocatalytic activity, were carefully optimized. WO3/TPW showed excellent photocatalytic activity compared to TPW for the degradation of Rh B dye pollutant under UV light for 30 min (94 %). Finally, the effective parameters on the value of Rh B dye degradation by WO3/TPW photocatalyst including pH, adsorbent dosage, the concentration of dye pollutant, and the kinetics of the degradation process were studied. It is expected that this type of photochemical modification method and natural WO3/TPW photocatalyst will be a promising path for the synthesis, modification, and increase of the photocatalytic performance of natural adsorbents.