Herein, we report the rational design of a simple hydrothermal reaction for the first time to prepare interlaced Sb2O3nanosheets and Sb2S3micro-nanospheres, grown on carbon fiber cloth, for application as flexible electrodes in sodium-ion batteries and sodium-ion capacitors with excellent electrochemical performance.

greenhouse gas effect and to simultaneously convert CO 2 to value-added industrial products. [1][2][3][4][5] However, the inertness of CO 2 molecule, the sluggish multi-electron transfer kinetics, and the competitive hydrogen evolution reaction (HER) during CO 2 RR result in the high overpotential (η) to various degrees, which jeopardizes CO 2 RR performance. [6,7] Therefore, it is highly desirable to develop the electrocatalysts that are capable of compromising the above impediments and simultaneously achieving the optimal CO 2 RR performance through specific optimization process.Formic acid (HCOOH) or formate, as an important liquid product from CO 2 RR, has been widely employed as chemical intermediates in various industrial processes. [8] The common industrial manufacture of HCOOH involves the carbonylation of methanol prior to the hydrolyzing of methyl formate. This process is performed in the liquid phase at elevated pressure, which is an energy-intensive and high-cost process. [9] In contrast, CO 2 RR to HCOOH requires a quite mild reduction condition. Currently, some metal-based materials (e.g., Sn, [10][11][12] Pb, [13][14][15] In, [16,17] and Cd [18,19] ) have been studied for HCOOH formation during CO 2 RR because of their suitable binding energy for the intermediate HCOO*. [20,21] However, the high cost and toxicity of these heavy metals (e.g., Pb, Cd, In, etc.) preclude their scalability. Remarkably, Bi-based materials have attracted much attention owing to their low toxicity, earth-abundance, and good selectivity toward formate formation. Various features of Bi-based materials, such as size, morphology, and electrocatalysts with conductive support, have been widely investigated to achieve enhanced electrocatalytic activity and selectivity. [22][23][24] Nevertheless, their low current density (j) and high overpotential are still the bottlenecks that restrict their practical applications at industrial level. [25,26] Therefore, it is of great importance to fabricate the highly effective and stable Bi-based electrocatalysts, to explore the associated reaction mechanism in order to achieve an improved selectivity toward formate.The complicated multi-electron transfer steps during CO 2 RR suggest the importance of charge transfer ability of electrocatalyst. [27,28] Various studies on Bi-based electrocatalysts, including the construction of Bi 2 O 3 nanosheets (NSs) on multi-channel carbon matrix support, [29] the fabrication of Bi 2 O 3 @C derived Electrochemical CO 2 reduction reaction (CO 2 RR) is a promising approach to convert CO 2 to carbon-neutral fuels using external electric powers. Here, the Bi 2 S 3 -Bi 2 O 3 nanosheets possessing substantial interface being exposed between the connection of Bi 2 S 3 and Bi 2 O 3 are prepared and subsequently demonstrate to improve CO 2 RR performance. The electrocatalyst shows formate Faradaic efficiency (FE) of over 90% in a wide potential window. A high partial current density of about 200 mA cm −2 at −1.1 V and an ultralow onset potential with formate FE of ...

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Perovskites with exsolved nanoparticles (P-eNs) have immense potentials for carbon dioxide (CO2) reduction in solid oxide electrolysis cell. Despite the recent achievements in promoting the B-site cation exsolution for enhanced catalytic activities, the unsatisfactory stability of P-eNs at high voltages greatly impedes their practical applications and this issue has not been elucidated. In this study, we reveal that the formation of B-site vacancies in perovskite scaffold is the major contributor to the degradation of P-eNs; we then address this issue by fine-regulating the B-site supplement of the reduced Sr2Fe1.3Ni0.2Mo0.5O6-δ using foreign Fe sources, achieving a robust perovskite scaffold and prolonged stability performance. Furthermore, the degradation mechanism from the perspective of structure stability of perovskite has also been proposed to understand the origins of performance deterioration. The B-site supplement endows P-eNs with the capability to become appealing electrocatalysts for CO2 reduction and more broadly, for other energy storage and conversion systems.

Three-dimensional (3D) binary oxides with hierarchical porous nanostructures are attracting increasing attentions as electrode materials in energy storage and conversion systems because of their structural superiority which not only create desired electronic and ion transport channels but also possess better structural mechanical stability. Herein, unusual 3D hierarchical MnCo2O4 porous dumbbells have been synthesized by a facile solvothermal method combined with a following heat treatment in air. The as-obtained MnCo2O4 dumbbells are composed of tightly stacked nanorods and show a large specific surface area of 41.30 m2 g–1 with a pore size distribution of 2–10 nm. As an anode material for lithium-ion batteries (LIBs), the MnCo2O4 dumbbell electrode exhibits high reversible capacity and good rate capability, where a stable reversible capacity of 955 mA h g–1 can be maintained after 180 cycles at 200 mA g–1. Even at a high current density of 2000 mA g–1, the electrode can still deliver a specific capacity of 423.3 mA h g–1, demonstrating superior electrochemical properties for LIBs. In addition, the obtained 3D hierarchical MnCo2O4 porous dumbbells also display good oxygen evolution reaction activity with an overpotential of 426 mV at a current density of 10 mA cm–2 and a Tafel slope of 93 mV dec–1.