Poly(vinyl pyrrolidone)-assisted hydrothermal synthesis and enhanced visible-light photocatalytic performance of oxygen-rich bismuth oxychlorides

Abstract

a b s t r a c tA series of novel oxygen-rich bismuth oxychloride (Bi 12 O 17 Cl 2 ) were synthesized through a facile poly (vinyl pyrrolidone) (PVP)-assisted hydrothermal route. These obtained Bi 12 O 17 Cl 2 samples were characterized by various physicochemical techniques. It was found that a proper addition amount of PVP could promote the transformation of Bi 12 O 17 Cl 2 morphology from irregular clusters to three-dimensional hierarchical flower-like microspheres that were nominated as sample BP2. As-synthesized samples were subjected to a photocatalytic degradation of dye Rhodamine B (RhB) or 2,4-dichlorophenol (2,4-DCP) under visible light. Among all candidates, the sample BP2 with a hierarchical flower-like morphology showed the best degradation efficiency for RhB and 2,4-DCP. The apparent rate constant of sample BP2 in terms of degradation of RhB was nearly 5.7 and 45 times that of unmodified BP0 and N-TiO 2 . The enhanced photocatalytic performance could be ascribed to synergetic effects including unique hierarchical morphologies, large specific surface area, small particle size, good crystallinity, and suitable band structures. A possible mechanism of catalytic degradation was finally proposed basing upon the active species trapping experiments.

Ag/Bi12O17Cl2 composite: A case study of visible-light-driven plasmonic photocatalyst

“…6. A broad intensive band with several weak peaks ranging from 400 to 600 nm is observed and ascribed to charge-transfer transitions between valance and conduction band, the surface-defect like oxygen vacancies generated from the fast growth rate, and different valence states of bismuth ions in Bi 12 O 17 Cl 2 [10,12]. The existence of deposited Ag can inhibit the radiative recombination of generated charge carriers [32].…”

“…The photocatalytic efficiency of bare Bi 12 O 17 C l2 can be improved by the morphological tailoring or the integration with other appropriate components [10][11][12]. Adequate morphologies such as nanowires, nanobelts, nanoplates, and three-dimensional hierarchical microflowers achieved by various synthetic protocols, are beneficial to shorten diffusion pathways, strengthen interfacial charge separation, and enhance light harvesting, therefore promoting photocatalytic degradation ability.…”

“…Till now, several cases of Ag/bismuth oxyhalide plasmonic photocatalysts have been reported [18][19][20]. However, to the best of our knowledge, the synthesis and photocatalytic evaluation of Ag/Bi 12 [10]. Typically, Bi(NO 3 ) 3 ·5H 2 O (3.84 mmol) was dissolved into a HCl aqueous solution (2 M, 25 mL) and the resultant transparent mixture was dropped with a NaOH aqueous solution (4 M, 20 mL).…”

In situ synthesis of porous ZnO-embedded Zn1−xCdxS/CdS heterostructures for enhanced photocatalytic activity

“…18 A large surface area usually means more surface sites, which could facilitate the adsorption and reaction of reactants and thus increase the photocatalytic activity due to the surface-based characteristic of the photocatalytic water splitting reaction. 23 With decreasing particle size, both ZnS and the relevant heterostructure show much larger nitrogen adsorption volumes and S BET (Fig. S5 †) than those prepared without NaOH.…”

Self-assembled micro and nano rod-shaped porphyrin@Bi12O17Cl2 composite as an efficient photocatalyst for degradation of organic contaminants

“…The value of n is 1 for direct transition and 4 for indirect transition. The BOC and Porph samples exhibit direct type transition [ 42 ] so n takes the value of 4. The band gap energy of BOC, 1%Porph@BOC, 10%Porph@BOC and Porph were estimated to be 2.51 eV, 1.47 eV, 1.77 eV and 1.71 eV, respectively.…”