Experimental and DFT insights on hydrothermally synthesized PbS doped bismuth titanate perovskites: An Outperforming photocatalytic hydrogen production performance

In present study, bismuth-based titanate perovskite nanomaterials have been prepared by adapting hydrothermal technique assisted with low temperature. The band gap calculated from the Tauc plot by diffused reflectance UV–visible spectroscopy is 3.25eV. Lead sulfide nanoparticles were mixed in different weight ratios of 0.1%,0.3% and 0.6%, as a dopant to the bismuth titanate perovskites leading to a decrease in the bandwidth. The elemental composition was confirmed by XPS indicating the existence Bi and Ti further, detects the presence of oxygen species in more than one states which likely improves the photocatalytic characteristics. The photocatalytic action for breakdown of water was observed by a photochemical reactor using a Xenon lamp as a source of light and the experiment was performed in proximity of various hole-emulsifying agents. It was noticed that 0.6% PbS doped bismuth titanate (BT) reveals the highest hydrogen production of 202.43 μmol/g in the presence of EDTA and for generation of hydrogen, decreasing order of scavenger's activity is Methanol > EDTA and TEOA for 0.6% PbS doped Bismuth titanates nanomaterials. Moreover, to achieve new and subtle insights in understanding the hydrogen adsorption phenomenon in the two selected composite models, DFT studies have been done. Since, the in-silico-based results (especially, the binding energy) provided evocative and interesting results (PbS side is more favorable than the Bi–O–Ti side for hydrogen production) which could be helpful for the experimentalists in smart fabrication of such fascinating materials employed for energy storage applications.