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There is currently a strong demand for energy storage devices which are cheap, light weight, flexible, and possess high power and energy densities to meet the various requirements of modern gadgets. Herein, we prepare a flexible and easily processed electrode via a simple ''brush-coating and drying'' process using everyday cotton cloth as the platform and a stable graphene oxide (GO) suspension as the ink. After such a simple manufacturing operation followed by annealing at 300 C in argon atmosphere, the as-obtained graphene sheets (GNSs)-cotton cloth (CC) composite fabric exhibits good electrical conductivity, outstanding flexibility, and strong adhesion between GNSs and cotton fibers. Using this GNSs-CC composite fabric as the electrode material and pure CC as the separator, a homemade supercapacitor was fabricated. The supercapacitor shows the specific capacitance of 81.7 F g À1 (two-electrode system) in aqueous electrolyte, which is one of the highest values for GNSs-based supercapacitors. Moreover, the supercapacitor also exhibits satisfactory capacitance in ionic-liquid/ organic electrolyte. An all-fabric supercapacitor was also fabricated using pure CC as separator and GNSs-CC composite fabric as electrode and current collector. Such a conductive GNSs-CC composite fabric may provide new design opportunities for wearable electronics and energy storage applications.

Business costs and energy/environmental concerns have increased interested in biomass materials for production of activated carbons, especially as electrode materials for supercapacitors or as solid-state adsorbents in CO₂ adsorption area. In this paper, waste celtuce leaves were used to prepare porous carbon by air-drying, pyrolysis at 600 °C in argon, followed by KOH activation. The as-prepared porous carbon have a very high specific surface area of 3404 m²/g and a large pore volume of 1.88 cm³/g. As an electroactive material, the porous carbon exhibits good capacitive performance in KOH aqueous electrolyte, with the specific capacitances of 421 and 273 F/g in three and two-electrode systems, respectively. As a solid-state adsorbent, the porous carbon has an excellent CO₂ adsorption capacity at ambient pressures of up to 6.04 and 4.36 mmol/g at 0 and 25 °C, respectively. With simple production process, excellent recyclability and regeneration stability, the porous carbon that was derived from celtuce leaves is among the most promising materials for high-performance supercapacitors and CO₂ capture.

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Electrochemical reduction of nitrate to ammonia (nitrate reduction reaction, NO3-RR) under ambient conditions, which overcomes the drawbacks of energy-intensive Haber−Bosch reaction and low-efficient N2 electroreduction, is one of the alternatives...

As an important model reaction, photocatalytic methanol dissociation on rutile TiO 2 (110) has drawn much attention, but its reaction mechanism remains elusive. Using DFT+U calculations, we investigate the whole dissociation process of methanol into formaldehyde with and without photogenerated holes, aiming to illustrate how the hole is involved in the dissociation. We find that the O−H dissociation of methanol is a heterolytic cleavage process and is likely to be thermally driven; the presence of a hole has no promotion on the barrier and enthalpy change. In contrast, the subsequent C−H bond cleavage follows the homolytic cleavage mode and is likely to be photochemically driven; great enhancement can be made in both kinetics and thermodynamics when holes are introduced. The essential roles of holes in promoting C−H dissociation are identified, and what kinds of catalytic reactions can or cannot be facilitated by holes is discussed. Our findings may considerably broaden the understanding of photocatalytic chemistry.

Cell voltage is a fundamental quantity used to monitor and control Li-ion batteries. The open circuit voltage (OCV) is of particular interest as it is believed to be a thermodynamic...

Luminol-based electrochemiluminescence (ECL) can be readily excited by various reactive oxygen species (ROS) electrogenerated with an oxygen reduction reaction (ORR). However, the multiple active intermediates involved in the ORR catalyzed with complex nanomaterials lead to recognizing the role of ROS still elusive. Moreover, suffering from the absence of the direct electrochemical oxidation of luminol at the cathode and poor transformation efficiency of O2 to ROS, the weak cathodic ECL emission of luminol is often neglected. Herein, owing to the tunable coordination environment and structure-dependent catalytic feature, single-atom catalysts (SACs) are employed to uncover the relationship between the intrinsic ORR activity and ECL behavior. Interestingly, the traditionally negligible cathodic ECL of luminol is first boosted (ca. 70-fold) owing to the combination of electrochemical ORR catalyzed via SACs and chemical oxidation of luminol. The boosted cathodic ECL emission exhibits electron-transfer pathway-dependent response by adjusting the surrounding environment of the center metal atoms in a controlled way to selectively produce different active intermediates. This work bridges the relationship between ORR performance and ECL behavior, which will guide the development of an amplified sensing platform through rational tailoring of the ORR activity of SACs and potential-resolved ECL assays based on the high-efficiency cathodic ECL reported.