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Porous BiOCl micro-flowers constructed from ultrathin nanosheets with nearly 100% {001} facets exposed were selectively prepared. The exposed {001} facets terminated with a high density of oxygen atoms and are not only favorable for the adsorption of the cationic dye RhB but also can accumulate the photogenerated electrons injected from excited RhB. These electrons can be captured by O(2) and transformed to reactive oxygen species, which possess a strong photooxidative ability to degrade the dye pollutants directly and easily. Therefore, the resultant BiOCl photocatalysts exhibit superior activity for indirect dye photosensitization degradation under visible light, with a rapid degradation rate and high photostability.

A novel ternary plasmonic Ag 3 VO 4 /AgBr/Ag hybrid photocatalyst was successfully fabricated via an in situ anion-exchange reaction between Ag 3 VO 4 and KBr, followed by light reduction. The obtained samples were characterized by X-ray diffraction, scanning electron microscopy, energydispersive X-ray spectroscopy, UV−visible diffuse-reflectance spectroscopy (UV−vis DRS), and X-ray photoelectron spectroscopy. The photocatalytic activities of obtained photocatalysts were measured by the degradation of Rhodamine B and methylene blue under visible-light irradiation (λ ≥ 400 nm). As-prepared Ag 3 VO 4 /AgBr/Ag plasmonic photocatalysts exhibit wide absorption in the visible-light region and display superior visible-light-driven photocatalytic activities in degradation of organic contamination compared with pristine Ag 3 VO 4 , Ag 3 VO 4 /AgBr, and AgBr/Ag. This enhanced photocatalytic activity is attributed to the synergistic effects between Ag 3 VO 4 /AgBr-based heterostructured semiconductor photocatalysis and the surface plasmon resonance (SPR) of Ag nanoparticles (NPs). On the basis of UV−vis DRS and valence band X-ray photoelectron spectroscopy, a possible mechanism of enhanced photocatalytic activity of Ag 3 VO 4 /AgBr/Ag is proposed; the vectorial electron transfer driven by the matching band potentials of AgBr and Ag 3 VO 4 and the SPR of Ag NPs contribute to its high photocatalytic activity and the improved stability. Therefore, the present study provides helpful insight into the design of novel and highly efficient visible-light photocatalysts in the future.

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Metal particles dispersed on supports are important to improve the catalytic activity of metals. Herein, ultrasmall platinum nanoparticles (Pt NPs) immobilized in viologen micelles have been prepared by reducing chloroplatinic acid with DMF in the presence of a viologen-based surfactant, which not only acts as the nucleation site of metal particle formation, but also is responsible for protecting the Pt NPs from further growth or aggregation. The viologen-templated Pt NPs remain stable for several months without any noticeable aggregation. The obtained Pt NPs-viologen micelles show higher catalytic activity and stability in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol by NaBH 4 as compared with unprotected Pt NPs. The high catalytic activity is due to the viologen shell around the Pt NPs, which results in the formation of ultrasmall Pt NPs and, more importantly, provides a high concentration of 4-NP near the Pt NPs-viologen micelles. Notably, viologen, as an electron transfer mediator, plays a key role in the high catalytic activity.

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