Here we demonstrate a magnetic resonance coupling based wireless triboelectric nanogenerator (TENG) and fully self-powered wireless sensors. By integrating a microswitch and an inductor with the TENG, the pulsed voltage output is converted into a sinusoidal voltage signal with a fixed frequency. This can be transmitted wirelessly from the transmit coil to the resonant-coupled receiver coil with an efficiency of 73% for a 5 cm distance between the two coils (10 cm diameter). Analytic models of the oscillating and coupled voltage signals for the wireless energy transfer are developed, showing excellent agreement with the experimental results. A TENG of 40 × 50 mm2 can wirelessly light up 70 LEDs or charge up a 15 μF capacitor to 12.5 V in ~90 s. The system is further utilized for two types of fully self-powered wireless chipless sensors with no microelectronic components. The technologies demonstrate an innovative strategy for a wireless ‘green’ power source and sensing.

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Single‐layered Cu‐In‐Ga‐Se precursors were fabricated by one‐step sputtering of a single quaternary Cu(In,Ga)Se2 (CIGS) chalcogenide target at room temperature, followed by post selenization using Se vapor obtained from elemental Se pellets. The morphological and structural properties of both as‐deposited and selenized films were characterized by X‐ray diffraction (XRD), Raman spectroscope and scanning electron microscope (SEM). The precursor films exhibited a chalcopyrite structure with a preferential orientation in the (112) direction. The post‐selenization process at high‐temperature significantly improved the quality of the chalcopyrite CIGS. The CIGS layers after post‐selenization were used to fabricate solar cells. The solar cell had an open‐circuit voltage Voc of 0.422 V, a short‐circuit current density J = 24.75 mA, a fill factor of 53.29%, and an efficiency of 7.95%. Copyright © 2010 John Wiley & Sons, Ltd.

Organometal halide perovskites have been considered as promising candidates for high‐performance low‐cost photodetectors. Nonetheless, as perovskite photodetectors are usually built on glass or polymer substrates, their UV‐C (200–280 nm) photodetection ability is quite limited due to the high absorption of glass or polymer substrates. Here, a uniform UV photodetector array which integrates perovskite photodiodes with inorganic CsPbBr3 quantum dot (QD) fluorophor is reported. CsPbBr3 quantum dot fluorophor not only acts as an efficient down‐conversion layer to convert UV light into 510 nm light, but also functions as a protective layer to prevent degradation of hybrid organic–inorganic perovskite by UV light. Compared to direct UV‐C (279 nm) detection with perovskite photodiode, the QD integrated photodetector shows a higher responsibility and detectivity to UV‐C, with values enhanced by 1 order in magnitude. This work provides a low‐cost and effective approach for all perovskite‐based UV‐C photodetectors and imagers.

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