Three dimensional carbon substrate materials for electrolysis of water

Water splitting is an important approach for energy conversion to obtain hydrogen and oxygen. Apart from solar water splitting, electrochemical method plays a key role in the booming field, and it is urgent to develop novel and efficient catalysts to accelerate water splitting reaction. Recently, newly emerging self-supported materials, especially three dimensional（3D） carbon substrate electrochemical catalysts, have attracted great attention benefiting from their fantastic catalytic performances, such as large surface area,enhanced conductivity, tunable porosity, and so on. This review summarizes the outstanding materials used for hydrogen evolution reaction and oxygen evolution reaction. And catalysts that acted as both anode and cathode in two-electrode systems for overall water splitting are introduced systematically. The opportunities and challenges of 3D carbon substrate materials for electrochemical water splitting are proposed.

Synthesis and luminescent properties of lanthanide-doped ScVO_4 microcrystals

High quality and monodispersed ScVO4 microcrystals were successfully synthesized via a mild hydrothermal route using NH4VO3 as vanadium source. The X-ray power diffraction（XRD） and field-emission scanning electron microscopy（FE-SEM） results indicated that the size, shape, and phase formation of the ScVO4 microcrystals could be tuned by altering the reaction temperature, reaction time, and p H value of the initial solution. Furthermore, the down- and upconversion luminescence of ScVO4：Ln（Ln=Eu, Dy, Sm, Yb/Ho, Yb/Er, and Yb/Tm） microcrystals were characterized and the respective energy transfer processes were also discussed. The experimental results demonstrated that reactions at 200 oC, 24 h, and pH=6 could generate perfect ScVO4 microcrystals, which were then used for luminescence studies.

Theoretical study of photon emission from single quantum dot emitter coupled to surface plasmons

Motivated by the recent pioneering advances on nanoscale plasmonics and also nanophotonics tech- nology based on the surface plasmons （SPs）, in this work, we give a master equation model in the Lindblad form and investigate the quantum optical properties of single quantum dot （QD） emitter coupled to the SPs of a metallic nanowire. Our main results demonstrate the QD luminescence results of photon emission show three distinctive regimes depending on the distance between QD and metallic nanowire, which elucidates a crossover passing from being metallic dissipative for much smaller emitter-nanowire distances to surface plasmon （SP） emission for larger separations at the vicinity of plasmonic metallic nanowire. Besides, our results also indicate that, for both the resonant case and the detuning case, through measuring QD emitter luminescence spectra and second-order correlation functions, the information about the QD emitter coupling to the SPs of the dissipative metallic nanowire can be extracted. This theoretical study will serve as an introduction to un- derstanding the nanoplasmonic imaging spectroscopy and pave a new way to realize the quantum information devices.