17 research outputs found
Experience gained from operation of the reverse-osmosis plant at the Novosibirsk TETs-2 cogeneration station
Selective Dissolution of Brass in the Molten Eutectic Mixture of Lithium, Sodium, and Potassium Carbonates
Effect of the structural state of the FePd equiatomic alloy on the temperature dependence of the initial magnetic susceptibility and the curie temperature
Size Dependence of Temperature-Related Optical Properties of PbS and PbS/CdS Core/Shell Quantum Dots
The effect of PbS core size on the temperature-dependent photoluminescence (PL) of PbS/CdS quantum dots (QDs) in the temperature range of 100-300 K was thoroughly investigated and compared with shell-free PbS QDs. The core/shell QDs show significantly smaller PL intensity variation with temperature at a smaller PbS size, while a larger activation energy when the PbS domain size is relatively large, suggesting both different density and different distribution of defects/traps in the PbS and PbS/CdS QDs. The most remarkable difference consists in the PbS size dependence of the energy gap temperature coefficient (dE/dT). The PbS/CdS QDs show unusual non-monotonic dE/dT variation, resulting in the reversal of the dE/dT difference between the PbS and PbS/CdS QDs at a larger PbS size. In combination with theoretical calculations, we find that, although lattice dilation and carrier-phonon coupling are generally considered as dominant terms, the unique negative contribution to dE/dT from the core/shell interfacial strain becomes most important in the relatively larger-core PbS@CdS QDs