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With the advantages of short charging and discharging times, high power density, and long cycle life, supercapacitors are regarded as one of the most promising energy storage devices and have garnered massive attention in the field of energy storage. This paper prepared La1−xCaxMnO3 (x=0, 0.05, 0.1, 0.15, and 0.2) nanoparticles by the sol‐gel method. The microstructure, morphology, and electrochemical performance of the samples were characterized. The results depict that La0.85Ca0.15MnO3 has a low charge transfer resistance (0.19 Ω) and a large specific surface area (38.79 m2 g−1). The maximum specific capacitance of the La0.85Ca0.15MnO3 sample reached 248 F/g at a current density of 0.5 A/g, which is ascribable to its large specific surface area and high oxygen vacancy concentration. The anion‐intercalation mechanism was investigated by the charging and discharging process. The above results depict that Ca‐doping significantly enhances the electrochemical performance of LaMnO3 system. [ABSTRACT FROM AUTHOR]

Self-powered photoelectric devices as a new type of sensor without an external power source have a great potential advantage in the next generation of portable and wearable personal devices. The design of those devices is normally based on three kinds of strategies: a p–n junction, the Schottky junction and ferroelectric polarization. Here, a novel solution based on ion migration induced self-powered photodetectors was explored. In this work, high quality halide perovskite FAPbBr3 crystals were grown by an inverse temperature crystallization (ITC) method. An irreversible ion migration was intentionally created using a symmetrically structured Au/FAPbBr3/Au device. The resulting built-in electric field and energy band bending were proved using electrical measurements in the dark and under light. Finally, the response of the ion migration induced self-powered FAPbBr3 detector was investigated with the values of R (∼0.18 mA W−1) and EQE (∼0.055%) under light with a power density of 1 mW cm−2 and a wavelength of 397 nm. Our investigation demonstrates that ion migration, which is normally deemed a detrimental factor for device stability, can be intentionally used for self-powered photoelectric devices. [ABSTRACT FROM AUTHOR]