Southwest University of Science and Technology

About: Southwest University of Science and Technology is a education organization based out in Mianyang, China. It is known for research contribution in the topics: Adsorption & Graphene. The organization has 10017 authors who have published 8923 publications receiving 94850 citations. The organization is also known as: Xīnán Kējìdàxué.

In3+-doped BiVO4 photoanodes with passivated surface states for photoelectrochemical water oxidation

Abstract: BiVO4 is a promising photoanode material for photoelectrochemical water splitting, but its actual activity is hindered by the high energy surface states. Here, we report that In3+ can be used as a dopant to substitute the partial sites of Bi3+ in BiVO4 for modifying the surface states and improving the water oxidation activity of a BiVO4 nanoflake film. Among the In3+-doped BiVO4 film photoanodes, the 7% In3+-doped BiVO4 film shows optimal photoelectrochemical water oxidation activity. At 1.23 V vs. RHE, the 7% In3+-doped BiVO4 photoanode exhibits a photocurrent density of 1.56 mA cm−2 in 0.1 M Na2SO4, which is over 200% greater than that of the undoped BiVO4 photoanode. In3+-doping did not change the morphology, phase and band gap of BiVO4 obviously, but resulted in a positive shift of the flat band position and higher surface charge separation efficiency for water oxidation. Density functional theory calculations indicate that the surface energy of BiVO4 decreased after In3+-doping that involved more unsaturated electrons of the Bi atom in the Bi–O bonds, thus reducing the amount of exposed unsaturated Bi atoms and broken Bi–O bonds. Therefore, the enhanced water oxidation activity on the In3+-doped BiVO4 photoanode can be ascribed to In3+-doping that passivated the surface states of BiVO4 and thus inhibited the surface charge recombination.

Sustainability-inspired cell design for a fully recyclable sodium ion battery.

Abstract: Large-scale applications of rechargeable batteries consume nonrenewable resources and produce massive amounts of end-of-life wastes, which raise sustainability concerns in terms of manufacturing, environmental, and ecological costs. Therefore, the recyclability and sustainability of a battery should be considered at the design stage by using naturally abundant resources and recyclable battery technology. Herein, we design a fully recyclable rechargeable sodium ion battery with bipolar electrode structure using Na3V2(PO4)3 as an electrode material and aluminum foil as the shared current collector. Such a design allows exceptional sodium ion battery performance in terms of high-power correspondence and long-term stability and enables the recycling of ∼100% Na3V2(PO4)3 and ∼99.1% elemental aluminum without the release of toxic wastes, resulting in a solid-component recycling efficiency of >98.0%. The successful incorporation of sustainability into battery design suggests that closed-loop recycling and the reutilization of battery materials can be achieved in next-generation energy storage technologies. Effective recycling technologies represent a solution to the sustainability and environmental consequences of spent rechargeable batteries. Here, the authors show a bipolar electrode design that allows not only good electrochemical performance but a closed loop of material use for sodium ion batteries.