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In this report, doping concentration-dependent photoluminescence (PL) properties of Mn-doped ternary Zn-In-S quantum dots (QDs) were studied by using steady-state and time-resolved PL spectroscopy. The QDs PL was firstly significantly intensified with the increasing Mn doping concentration and then decreased after the doping concentration increased up to 7.5 at.%. However, their decay lifetimes exhibit a monotone decrease with Mn doping concentration ranged from 0 to 10 at.%. It can be concluded that the PL intensity was mainly determined by two factors: one was the increased efficiency of energy transfer from host excitons to Mn ion accepter, and the other was the decreased efficiency of the emission from a Mn ion, which was caused by the increased component of exposed Mn ions on QDs surface and the accelerated interaction between adjacent dopants. The competition of above two exciton relaxation dynamics processes determined the trend of the PL intensity, while the latter was responsible for the monotonously decreased lifetime of the Mn ion emission with the increasing Mn doping concentration. [ABSTRACT FROM AUTHOR]

Improving the photocatalytic efficiency of TiO semiconductor is crucially important and highly desired for its practical applications. In the present work, aiming to broaden the photoresponse window and limit the photocatalyst aggregation, we reported the exploration of N-doped TiO thoroughly mesoporous nanofibers with high purity in morphology via a foaming-assisted electrospinning strategy. The foaming agents and urea were introduced in the raw materials to create the mesopores and incorporate the N dopants into the conventional solid TiO nanofibers, respectively, which could be accomplished simultaneously over one-step calcination process. The synergetic combination of N dopants and one-dimensional mesoporous nanostructure allow the TiO fibers to exhibit significantly enhanced visible-light photocatalytic activity toward the Rhodamine B and hydrogen evolution, as compared to those of N-doped solid and intrinsic thoroughly mesoporous counterparts, suggesting their promising applications in water purification and energy supply. [ABSTRACT FROM AUTHOR]