In situ preparation of PDA decorated Ag/black mesoporous TiO2 nanocomposites for photocatalytic and antibacterial applications

The transparent photovoltaic NiO/TiO2 orderly nanoarray pn junction via synergism of AgInS2 quantum dots and Ti3+ self-doping

“…Thus, Ti 3+ /O v is introduced successfully by the reduction process of CaH 2 . [37][38][39] The peaks at 853.02 and 870.84 eV are from Ni 2+ ions, and the peaks at 855.05 and 873.03 eV are from the Ni 3+ ions (Fig. 2(k)).…”

“…[12][13][14][22][23][24] With reduction, the band gaps of Ti 3+ -TiO 2 exhibit a continuous decrease to 2.893 (Ti 3+ TiO 2 -1), 2.853 (Ti 3+ TiO 2 -2), 2.842 (Ti 3+ TiO 2 -3) and 2.831 (Ti 3+ TiO 2 -4) eV. [37][38][39] Such appropriate band gaps would be the main reason for these NiO/Ti 3+ -TiO 2 pn junctions to maintain good transparency after introducing of Ti 3+ /O v . The decreased band gap would also be evidence for the new potential caused by the Ti 3+ /O v .…”

“…Significantly, a remarkable intermediate band appears near the CB of Ti 3+ -TiO 2 . Herein, this shallow donor level caused by the O v can boost the solar efficiency to increase the photogenerated carrier, [37][38][39]65 so that the kinetic equilibrium for enhancing the photovoltaic conversion efficiency can be optimized.…”

“…Thus, the structure maintains good stability. [37][38][39] Because of the lower concentration of AgInS 2 QDs and weak crystallinity of the NiO film, their characteristic diffraction peaks are hardly observed in the formed AgInS 2 QDs/NiO/Ti 3+ -TiO 2 pn junction. However, two diffraction peaks at 27.49 and 46.451 can be observed in the single AgInS 2 QDs, and are attributed to the (006) and ( 018) planes (PDF#01-075-2379), [52][53][54][55] respectively.…”

“…37 Ding et al also prepared Ag/Ti 3+ -TiO 2 nanocomposites to improve the environmental photocatalytic properties. 38 Additionally, the oxygen vacancy (O v ) induced by the Ti 3+ ions can advance the kinetic potential energy via potential gradient regulation, 39 so that the charge carrier separation and transportation can be accelerated. Furthermore, the reduction process can optimize the pn junction interface by decreasing the defects and improving the crystalline quality.…”