Unraveling Mechanisms of Highly Efficient Yet Stable Electrochemiluminescence from Quantum Dots.

With CdSe/CdS/ZnS core/shell/shell quantum dots (QDs) as the model system, time- and potential-resolved spectroelectrochemical measurements are successfully applied for studying the general mechanisms and kinetics of electrochemiluminescence (ECL) generation. The rate constant of electron injection from the cathode into a QD to form a negatively charged QD (QD) increases monotonically from -0.88 V to -1.

Band-Edge Energy Levels of Dynamic Excitons in Cube-Shaped CdSe/CdS Core/Shell Nanocrystals.

An electron-hole pair in a cube-shaped CdSe/CdS core/shell nanocrystal exists in the form of dynamic excitons across the strongly and weakly confined regimes under ambient temperatures. Photochemical doping is applied to distinguish the band-edge electron and hole levels, confirming an effective mass model with universal constants. Reduction of the optical bandgap upon epitaxy of the CdS shells is caused by lowering the band-edge electron level and barely affecting the band-edge hole level.

Bifunctional covalent bromine: an advanced redox mediator for rechargeable lithium-oxygen batteries.

In this work, we introduce trimethylbromosilane (CHSiBr), which can protect lithium metal anodes an formed SEI layer while catalyzing the decomposition of LiO. As a result, lithium-oxygen batteries with CHSiBr offer a long cycle life of 110 cycles with a significantly reduced charging/discharging overpotential.