Mesoporous Ta3N5Microspheres Prepared from a High-Surface-Area, Microporous, Amorphous Precursor and Their Visible-Light-Driven Photocatalytic Activity

Constructing Rh–Rh3+ modified Ta2O5@TaON@Ta3N5 with special double n–n mutant heterojunctions for enhanced photocatalytic H2-evolution

A multiple core–shell heterostructure Rh–Rh³⁺ modified Ta₂O₅@TaON@Ta₃N₅ nanophotocatalyst was successfully constructed through nitriding Rh³⁺-doped Ta₂O₅ nanoparticles, which exhibited a much higher carrier separation efficiency about one order of magnitude higher than the Ta₂O₅@Ta₃N₅ precursor, and thus an excellent visible light photocatalytic H₂-evolution activity (83.64 μmol g⁻¹ h⁻¹), much superior to that of Rh anchored Ta₂O₅@TaON (39.41 μmol g⁻¹ h⁻¹), and improved stability due to the residual Rh–O/N in the Ta₃N₅ shell layer. Rh-modifying significantly extended light absorption to the overall visible region. Localized built-in electric fields with hierarchical potential gradients at the multiple interfaces including a Rh/Ta₃N₅ Schottky junction and double n–n Ta₃N₅/TaON/Ta₂O₅ mutant heterojunctions, drove charge carriers to directionally transfer from inside to outside, and efficiently separate. Enhanced photoactivity was ascribed to a synergetic effect of improved light absorption ability, increased carrier separation efficiency, and accelerated surface reaction. A promising strategy of developing excellent Ta₃N₅-based photocatalysts for solar energy conversion is provided by constructing double n–n mutant heterojunctions.

Localized built-in electric fields at multiple hierarchical interfaces facilitate the efficient separation and fast inside-out directional transfer of photogenerated carriers.

Synthesis of free-standing Ta3N5nanotube membranes and flow-through visible light photocatalytic applications

We report on free-standing Ta₃N₅nanotubular membranes with open top and bottom, used as visible-light-active, flow-through photocatalytic micro-reactors.

Role of Oxygen Defects on the Photocatalytic Properties of Mg-Doped Mesoporous Ta3 N5

Tantalum nitride (Ta3 N5 ) highlights an intriguing paradigm for converting solar energy into chemical fuels. However, its photocatalytic properties are strongly governed by various intrinsic/extrinsic defects. In this work, we successfully prepared a series of Mg-doped mesoporous Ta3 N5 using a simple method. The photocatalytic and photoelectrochemical properties were investigated from the viewpoint of how defects such as accumulation of oxygen and nitrogen vacancies contribute to the catalytic activity. Our findings suggest that Mg doping is accompanied by an accumulation of oxygen species and a simultaneous elimination of nitrogen vacancies in Ta3 N5 . These oxygen species in Ta3 N5 induce delocalized shallow donor states near the conduction band minimum and are responsible for high electron mobility. The superior photocatalytic activity of Mg-doped Ta3 N5 can then be understood by the improved electron-hole separation as well as the lack of nitrogen vacancies, which often serve as charge-recombination centers.

Hierarchical photocatalysts

The design, fabrication, performance and applications of hierarchical semiconductor photocatalysts are thoroughly reviewed and apprised.

Effects of oxygen impurities and nitrogen vacancies on the surface properties of the Ta3N5 photocatalyst: a DFT study

Surface defects and impurities play important roles in the photocatalytic performance of semiconductors. In this study, DFT calculations are performed to investigate the effects of oxygen impurities and nitrogen vacancies on the surface stability and electronic structures of Ta3N5(100), (010) and (001) low-index surfaces. The results show that, for each surface, the oxygen impurities and nitrogen vacancies are beneficial and harmful, respectively, to the surface stability of Ta3N5. The oxygen impurities and nitrogen vacancies have mainly two effects on the surface electronic structures of Ta3N5. One is saturating surface states on the clean surface, and the other is inducing the downshift of conduction band minimum. In addition, the Ta3N5(100) surface with oxygen impurities is expected to have the strongest reduction ability in practice, providing useful guidance for further investigations of Ta3N5 in the photocatalytic hydrogen evolution.

Monolithic organic/inorganic ternary nanohybrids toward electron transfer cascade for enhanced visible-light photocatalysis

Monolithic organic/inorganic ternary nanohybrids were facilely prepared toward electron transfer cascade and demonstrated enhanced visible-light photocatalytic activity.