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The quantum dot (QD) color-conversion efficiency (CCE) in GaN micro-light-emitting diodes ( $\mu $ LEDs) is greatly improved by non-radiative energy transfer (NRET) mechanism. An array of deep nano-holes with a diameter of about $1~\mu \text{m}$ was fabricated in $\mu $ LED mesas ( $40\times 60\,\,\mu \text{m}^{2}$ ) by nanoimprint lithography. The nano-holes were etched straight through the $\mu $ LED active region to ensure that the filled QDs were in extremely close contact with the active region. The absorption efficiency and emission efficiency of QDs are effectively improved by NRET, resulting in a superhigh CCE in QD- $\mu $ LED hybrid devices. Compared to $\mu $ LED devices with conventional spin-coated QDs, the CCE of novel nano-hole $\mu $ LEDs with filled QDs has been enhanced by about 118%.

A strategy for the application of localized surface plasmon to Micro-LED is proposed in this paper. The quantum wells region is exposed by direct etching and Ag nanoparticles is used to generate localized surface plasmon.

In the present study, the ZnO-porous carbon (ZnO-C) composites were prepared by pyrolyzing MOF-74 (Zn) precursor at different pyrolysis temperatures. The ZnO-C composites were endowed with ultrafast organic dye adsorption capability and promising supercapacitance properties due to the existence of abundant pores within the composite structures. Having a surface area of 782.971 m2/g and pore volume of 0.698 m3/g, the composite pyrolyzed at 1000 °C (ZnO-C1000) exhibited the best performance for organic pollutant uptake. Specifically, 50 mg of ZnO-C1000 could remove all the Rhodamine B dye from 100 mL aqueous solution within 0.5 h even the dye concentration was as high as 40 mg/L. It was also shown that the ZnO-C composites could preserve their adsorption capability in a wide pH range, and keep promising dye adsorption stability after consecutive adsorption/desorption cycles. Furthermore, the ZnO-C900 exhibited a specific capacitance of 197.84 F/g as the supercapacitance electrode with good stability (∼97.8% capacitance retention after 1000 cycles). The overall results indicate that the prepared ZnO-C composites have multi-application potentials which can be utilized as efficient pollutant absorbents as well as electrode materials for supercapacitors.

A binder free electrode is fabricated by “planting” Anderson type polyoxometalate derived NiS/MoS2 “follower” on functional carbon paper. This electrode shows excellent UOR activity. In 1 ​M KOH containing 0.4 ​M urea, it only needs 1.42 and 1.43 ​V voltage to achieve 50 and 100 ​mA ​cm−2 current. On the contrary, to reach 50 and 100 ​mA ​cm−2, OER require 1.68 and 1.75 ​V. Besides promising UOR activity, the HER property of this electrode is also attractive. In urea containing electrolyte, its η10 and η100 are only 128 and 283 ​mV. More importantly, it shows excellent stability in both UOR and HER. In electrolytic cell, with this electrode as cathode and anode simultaneously, only 1.42 and 1.49 ​V voltage is needed to obtain 10 and 50 ​mA ​cm−2 current in urea containing electrolyte. Without urea, the voltages increase to 1.69 and 1.75 ​V. The excellent UOR and HER properties suggest this binder free electrode is competent for low energy consumption H2 production.