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Generating oxygen vacancies (Vö) in vanadium pentoxide (V 2 O 5 ) has been demonstrated as an effective approach to tailor its electrochemical properties. The present study investigates three different kinds of conductive polymer (CP = PPy, PEDOT, and PANI) coated V 2 O 5 nanofibers with Vö generated at the interface during the polymerization process. Surface Vö form a local electric field and promote the charge transfer kinetics of the resulting Vö-V 2 O 5 /CP nanocables, and the accompanying V 4+ and V 3+ ions may also catalyze the redox reactions and improve the supercapacitor performance. The differences and similarities of three different CP coatings have been compared and discussed, and are dependent on their polymerization conditions and coating thickness. The distribution of Vö in the surface layer and in the bulk has been elaborated and the corresponding effects on the electrochemical properties and supercapacitor performance have also been investigated. Vö-V 2 O 5 /CP can deliver a high capacity of up to 614 F g −1 at a current rate of 0.5 A g −1 and supercapacitors with Vö-V 2 O 5 /CP demonstrated excellent cycling stability over 15 000 cycles at a rate of 10 A g −1 . 

Abstract A local electric field is induced to engineer the interface of vanadium pentoxide nanofibers (V₂O₅‐NF) to manipulate the charge transport behavior and obtain high‐energy and durable supercapacitors. The interface of V₂O₅‐NF is modified with oxygen vacancies (Vö) in a one‐step polymerization process of polyaniline (PANI). In the charge storage process, the local electric field deriving from the lopsided charge distribution around Vö will provide Coulombic forces to promote the charge transport in the resultant Vö‐V₂O₅/PANI nanocable electrode. Furthermore, an ≈7 nm porous PANI coating serves as the external percolated charge transport pathway. As the charge transfer kinetics are synergistically enhanced by the dual modifications, Vö‐V₂O₅/PANI‐based supercapacitors exhibit an excellent specific capacitance (523 F g⁻¹) as well as a long cycling lifespan (110% of capacitance remained after 20 000 cycles). This work paves an effective way to promote the charge transfer kinetics of electrode materials for next‐generation energy storage systems. 

Abstract The ever‐increasing demand for clean sustainable energy has driven tremendous worldwide investment in the design and exploration of new active materials for energy conversion and energy‐storage devices. Tailoring the surfaces of and interfaces between different materials is one of the surest and best studied paths to enable high‐energy‐density batteries and high‐efficiency solar cells. Metal‐halide perovskite solar cells (PSCs) are one of the most promising photovoltaic materials due to their unprecedented development, with their record power conversion efficiency (PCE) rocketing beyond 25% in less than 10 years. Such progress is achieved largely through the control of crystallinity and surface/interface defects. Rechargeable batteries (RBs) reversibly convert electrical and chemical potential energy through redox reactions at the interfaces between the electrodes and electrolyte. The (electro)chemical and optoelectronic compatibility between active components are essential design considerations to optimize power conversion and energy storage performance. A focused discussion and critical analysis on the formation and functions of the interfaces and interphases of the active materials in these devices is provided, and prospective strategies used to overcome current challenges are described. These strategies revolve around manipulating the chemical compositions, defects, stability, and passivation of the various interfaces of RBs and PSCs.