Exploring cheap and efficient oxygen evolution reaction (OER) catalysts is extremely vital for the commercial application of advanced energy storage and conversion systems. Herein, a self-supporting Co3S4/ S-doped reduced graphene oxide ( Co3S4/S-rGO) film catalyst is successfully prepared by a blade coating coupled with high-temperature annealing strategy, and its morphology, structure and composition are measured and analyzed. It is substantiated that the as-synthesized Co3S4/ S-rGO film possesses unique self-supporting structure, and is composed of uniformly dispersed Co3S4 nanoparticles and highly conductive S-rGO, which benefit the exposure of catalytic sites and electron transfer. By reason of the synergistic effect of the two individual components, the self-supporting Co3S4/ S-rGO film catalyst displays outstanding catalytic performance towards OER. As a consequence, the Co3S4/ S-rGO film catalyst delivers an overpotential of 341 mV at 10 mA cm-2, and the current attenuation rate is only 2.6% after continuous operation for 4 h, verifying excellent catalytic activity and durability. Clearly, our results offers a good example for the construction of high-performance self-supporting carbon-based composite film catalysts for critical electrocatalytic reactions.

With the rapid development of flexible wearable electronic products, flexible all graphene-based supercapacitors (FGSCs) with reduced graphene oxide rGO//graphene oxide (GO)//rGO structure have attracted substantial attention due to their unique structures and energy storage mechanism. However, restricted by design idea and preparation technology, improvement of capacitance performance for the FGSCs is not obvious recently. Herein, we demonstrate that an interface integration strategy of constructing the high-performance FGSCs with compact structure. Hydroquinone (HQ)-modified rGO (HQ-rGO) films (electrode materials) and sulfuric acid-intercalated GO films (electrolyte/separator) are assembled into the FGSCs utilizing hydrogen bonding and capillary contractility. The HQ further improves the electrochemical capacitance of electrode materials. The synergistic effect of the hydrogen bonding and capillary contractility guarantees compact and stable structure of the device. The resulting FGSCs exhibit an excellent areal capacitance of 804.6 mF cm− 2 (@2 mA cm− 2) and 441 mF cm− 2 (@30 mA cm− 2), and their highest energy and power densities can achieve 109.5 μWh cm− 2 and 21,060 μW cm− 2, respectively. These performances are superior to other all-in-one graphene-based SCs reported. Therefore, the construction technology of the FGSCs is a promising for developing all graphene-based SCs with high-performance.

Transition-metal phosphides (TMPs), a promising anode material for lithium-ion batteries (LIBs), are limited in application because of its serious volume effect in the cycle. In this work, a simple electrospinning strategy was proposed to restrict the grain size of CoP nanocrystals by nano-confined effect of carbon nanofibers with ligands. The addition of ligands not only could realize the uniform dispersion of CoP nanocrystals, but also strengthen the bond between the metals and carbon nanofibers. As a result, the CoP/CNF composite exhibits excellent lithium storage performance, and its reversible specific capacity could reach 1016.4 mAh g− 1 after 200 cycles at a current density of 200 mA g− 1. The research is anticipated to provide a new idea for the preparation of anode materials for lithium ion batteries.