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Tremendous achievements of colloidal quantum-dot (QD) light-emitting diodes (QLEDs) in both efficiency and lifetime have been witnessed in the past decade. However, multiple interfacial losses such as defect-induced exciton quenching and multicarrier Auger recombination can severely suppress the device performance of QLEDs. Here, we present the efficient QLEDs by adopting the new liquid-solid-solution processed magnesium-doped zinc oxide nanocrystals (ZMO-LSS) as an electron-transport layer. A magic carrier relaxation dynamics is demonstrated at the QD emitter/ZMO-LSS interface for abnormal exciton recycling and enhanced radiative recombination, which arises from the subtle intragap band coupling of surface trap states as directly clarified by the prolonged electroluminescence decays of devices. Red-emitting QLEDs on rigid glass achieve a maximum external quantum efficiency (EQE) of 22.3% with virtual droop-free over a wide range of brightness from 10,000 to 200,000 cd m−2. By further combining a silver nanowires-based composited electrode on a plastic substrate, a substantial boost in EQE up to 24.0% is realized for flexible devices. The present results provide an in-depth study on interfacial recombination and convey a clear picture of constructing ZMO-LSS for efficient QLEDs and related optoelectronic devices.

The switching control strategy needs to design the switching surface and the control signal. In this paper, the control effect and the control process are studied for different control strategy based on dynamics method. For autonomous van der pol system, the orbit can be suppressed to an equilibrium when the switching-surface is chose to include equilibrium; otherwise the orbit only can be controlled to a sliding limit cycle of small amplitude. Crossing-sliding bifurcation and switching-sliding bifurcation is common route from crossing orbit to full-sliding orbit, and grazing-sliding bifurcation is common route from crossing orbit to equilibrium. The control strategy is robust to the disturbance of parameter and control signal once the steady full-sliding orbit is achieved.