Aqueous zinc ion batteries (ZIBs) are truly promising contenders for the future large-scale electrical energy storage applications due to their cost-effectiveness, environmental friendliness, intrinsic safety, and competitive gravimetric energy density. In light of this, massive research efforts have been devoted to the design and development of high-performance aqueous ZIBs; however, there are still obstacles to overcome before realizing their full potentials. Here, the current advances, existing limitations, along with the possible solutions in the pursuit of cathode materials with high voltage, fast kinetics, and long cycling stability are comprehensively covered and evaluated, together with an analysis of their structures, electrochemical performance, and zinc ion storage mechanisms. Key issues and research directions related to the design of highly reversible zinc anodes, the exploration of electrolytes satisfying both low cost and good performance, as well as the selection of compatible current collectors are also discussed, to guide the future design of aqueous ZIBs with a combination of high gravimetric energy density, good reversibility, and a long cycle life.

Expanding hydrated vanadate with transition metal cations collectively promotes and catalyzes fast and more Zn-ion intercalation in aqueous batteries.

This article summarizes our most recent studies on improved Li+‐intercalation properties in vanadium oxides by engineering the nanostructure and interlayer structure. The intercalation capacity and rate are enhanced by almost two orders of magnitude with appropriately fabricated nanostructures. Processing methods for single‐crystal V2O5 nanorod arrays, V2O5·n H2O nanotube arrays, and Ni/V2O5·n H2O core/shell nanocable arrays are presented; the morphologies, structures, and growth mechanisms of these nanostructures are discussed. Electrochemical analysis demonstrates that the intercalation properties of all three types of nanostructure exhibit significantly enhanced storage capacity and rate performance compared to the film electrode of vanadium pentoxide. Addition of TiO2 to orthorhombic V2O5 is found to affect the crystallinity, microstructure, and possible interaction force between adjacent layers in V2O5, and subsequently leads to enhanced Li+‐intercalation properties in V2O5. The amount of water intercalated in V2O5 is found to have a significant influence on the interlayer spacing and electrochemical performance of V2O5·n H2O. A systematic electrochemical study has demonstrated that the V2O5·0.3 H2O film has the optimal water content and exhibits the best Li+‐intercalation performance.

The influences of morphology and thickness of zinc oxide (ZnO) buffer layers on the performance of inverted polymer solar cells are investigated. ZnO buffer layers with different morphology and thickness varying from several nanometers to ≈55 nm are fabricated by adjusting the concentration of the precursor sol. The ZnO buffer layers with nearly same surface quality but with thickness varying from ≈7 to ≈65 nm are also fabricated by spinning coating for comparison. The photovoltaic performance is found to be strongly dependent on ZnO surface quality and less dependent on the thickness. The use of dense and homogenous ZnO buffer layers enhances the fill factor and short‐circuit current of inverted solar cell without sacrificing the open‐circuit voltage of device due to an improvement in the contact between the ZnO buffer layer and the photoactive layer. Inverted devices with a dense and homogenous ZnO buffer layer derived from 0.1 M sol exhibit an overall conversion efficiency of 3.3% which is a 32% increase compared to devices with a rough ZnO buffer layer made from 1 M sol, which exhibited a power conversion efficiency of 2.5%. The results indicate that the efficiency of inverted polymer solar cells can be significantly influenced by the morphology of the buffer layer.

Perovskite large-scale solution manufacturing methods combined with relevant crystallization thermodynamics and kinetics, as well as challenges including stability, toxicity, and module cost issues towards commercialization are reviewed.

This paper reports a study on template-growth and electrochemical properties of single-crystal vanadium pentoxide (V 2 O 5 ) nanorod arrays from VOSO 4 aqueous solution using electrochemical deposition. Uniformly sized vanadium oxide nanorods with a length of about 10 µm with diameters ranging from 100 to 200 nm were grown over a large area with near unidirectional alignment. These nanorods have single-crystalline structure with a growth direction of [010]. Electrochemical property analysis indicates that nanorod array electrodes have significantly higher current density and energy storage density than sol-gel-derived V 2 O 5 films.

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In this paper, we report the significant effects of dye loading conditions on the overall light conversion efficiency of zinc oxide (ZnO) film electrodes in dye-sensitized solar cells. A comparison of the ZnO film electrodes was also made with TiO 2 film electrodes prepared with similar dye loading conditions. It was found that using a higher and lower dye concentration requires a shorter and longer immersion time, respectively, for optimal sensitization of ZnO to obtain maximum efficiencies. A similar trend was found for the TiO 2 film electrode as well; however, smaller differences in the overall light conversion efficiencies were observed with varying dye concentration and immersion time. It was found that the chemical stability was an issue for the ZnO film electrodes but was not pertinent for the TiO 2 film electrodes. The film quality and structure of the ZnO film differed after prolonged immersion in high dye concentration, where the formation of N3 dye and Zn 2+ aggregates and/or the deterioration of the ZnO colloidal spheres and nanoparticles on the surface may have occurred. On the other hand, the film quality and structure of the TiO 2 film was not appreciably affected by prolonged immersion in high dye concentration, where the nanoparticle structure was not affected.