Many efforts have been made to develop bifunctional electrocatalysts to facilitate overall water splitting. Here, a fibrous bifunctional 3D electrocatalyst is reported for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) with high performance. The remarkable electrochemical performance is attributed of the catalysts to a number of factors: the metallic character of the three components (i.e., Ni3N, CoN, and NiCo2O4); the electronic structure, nanoflake‐nanosphere network with abundant electroactive sites, and the electric field effect at the interfaces between different components. The oxide–nitride/graphite fibers have the lowest overpotential requirements of 71 and 183 mV at 10 mA cm−2 for HER and OER in alkaline medium, respectively. These values are comparable to those of commercial Pt/C (20 wt%) and RuO2. The electrodes also show a response to HER and OER in both neutral and acid media. Furthermore, the 3D structure can be highlighted by all‐round electrodes for overall water splitting. The calculations on the changes in electrons transfer and the Femi level from oxides to oxides/nitrides reveal that the observed superb electrocatalytic performance can be attributed to the presence of Ni3N and CoN derived from the in situ nitridation of NiCo2O4.

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An IR-driven photocatalytic water splitting system based on WO2-NaxWO3 (x > 0.25) hybrid conductor materials was established for the first time; this system can be directly applied in seawater. The WO2-NaxWO3 (x > 0.25) hybrid conductor material was readily prepared by a high-temperature reduction process of semiconductor NaxWO3 (x < 0.25) nanowire bundles. A novel ladder-type carrier transfer process is suggested for the established IR-driven photocatalytic water splitting system.

Carbon materials display appealing physical, chemical, and mechanical properties and have been extensively studied as supercapacitor electrodes. The surface engineering further allows us to tune their capability of adsorption/desorption and catalysis. Therefore, a facile and inexpensive chemical-acid-etching approach has been developed to activate the carbon cloth as an electrode for supercapacitor. The capacitance of the acid-etched carbon cloth electrode can approach 5310 mF cm–2 at a current density of 5 mA cm–2 with remarkable recycling stability. The all-solid-state symmetric supercapacitor delivered a high energy density of 4.27 mWh cm–3 at a power density of 1.32 W cm–3. Furthermore, this symmetric supercapacitor exhibited outstanding mechanical flexibility, and the capacity remained nearly unchanged after 1000 bending cycles.