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Heteroatom‐doped carbon (HDC) has attracted tremendous attention due to its promising application in energy conversion and storage. Herein, due to its abundance high rate of reproduction, the microorganism, Bacillus subtilis, is selected as a precursor. An effective ionothermal process is adopted to produce the HDCs. Using acid activation, the obtained sample exhibits excellent electrocatalytic activity, long‐term stability, and excellent resistance to crossover effects in oxygen reduction. Additionally, the base‐treated sample exhibits superior performance in capacitors to most commercially available carbon materials. Even at a high current density, a relatively high capacitance is retained, indicating a great potential for direct application in energy storage.

The trends in miniaturization of electronic devices give rise to the attention of energy harvesting technologies that gathers tiny wattages of power. Here this study demonstrates an ultrathin flexible single electrode triboelectric nanogenerator (S‐TENG) which not only could harvest mechanical energy from human movements and ambient sources, but also could sense instantaneous force without extra energy. The S‐TENG, which features an extremely simple structure, has an average output current of 78 μA, lightening up at least 70 LEDs (light‐emitting diode). Even tapped by bare finger, it exhibits an output current of 1 μA. The detection sensitivity for instantaneous force sensing is about 0.947 μA MPa−1. Performances of the device are also systematically investigated under various motion types, press force, and triboelectric materials. The S‐TENG has great application prospects in sustainable wearable devices, sustainable medical devices, and smart wireless sensor networks owning to its thinness, light weight, energy harvesting, and sensing capacities.

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Poly(o-phenylenediamine) (POPD)-derived functional carbon materials with excellent capacitive performance are successfully synthesized by means of an integrated one-step process, in which FeCl(3) not only oxidizes the polymerization of the organic monomers but also activates the carbonization. Furthermore, extensive research has proved that this strategy to discover novel carbons is useful not only for capacitors but also for other energy storage/conversion devices.

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In this work, a one-dimensional microrod-based three-dimensional flowerlike indium hydroxide (In(OH) 3 ) structure was fabricated, without any templates or surfactants, using a well-known hydrothermal approach at a non-high temperature. In 2 O 3 with similar morphology was formed by annealing In(OH) 3 precursors and was characterized by Raman spectrum and photoluminescence (PL) spectrum in detail. The properties of the obtained In(OH) 3 composites were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, and thermogravimetric analysis. The effects of the experimental parameters such as the alkaline source selection, the concentration of urea, and the temperature on the morphology are discussed. These results indicate that the aligned superstructure originated from the oriented attachment of small particles.

As a representative natural polymer with abundant functionalities, humic acid was creatively explored as an anode material for lithium ion batteries and sodium ion batteries with high storage capacities, and satisfactory cycling stabilities. Most impressively, this work provides a promising and effective strategy for developing organic energy storage devices from natural sources.