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Lithium metal anodes have attracted extensive attention owing to their high theoretical specific capacity. However, the notorious reactivity of lithium prevents their practical applications, as evidenced by the undesired lithium dendrite growth and unstable solid electrolyte interphase formation. Here, we develop a facile, cost-effective and one-step approach to create an artificial lithium metal/electrolyte interphase by treating the lithium anode with a tin-containing electrolyte. As a result, an artificial solid electrolyte interphase composed of lithium fluoride, tin, and the tin-lithium alloy is formed, which not only ensures fast lithium-ion diffusion and suppresses lithium dendrite growth but also brings a synergistic effect of storing lithium via a reversible tin-lithium alloy formation and enabling lithium plating underneath it. With such an artificial solid electrolyte interphase, lithium symmetrical cells show outstanding plating/stripping cycles, and the full cell exhibits remarkably better cycling stability and capacity retention as well as capacity utilization at high rates compared to bare lithium., Here the authors report a simple method to create a solid electrolyte interphase that is tightly anchored onto the surface of lithium metal anode. This artificial structure suppresses dead and dendrite Li and stores Li via formation of alloys, enabling impressive battery performance.

Perovskites have been unprecedented with a relatively sharp rise in power conversion efficiency in the last decade. However, the polycrystalline nature of the perovskite film makes it susceptible to surface and grain boundary defects, which significantly impedes its potential performance. Passivation of these defects has been an effective approach to further improve the photovoltaic performance of the perovskite solar cells. Here, we report the use of a novel hydrazine-based aromatic iodide salt or phenyl hydrazinium iodide (PHI) for secondary post treatment to passivate surface and grain boundary defects in triple cation mixed halide perovskite films. In particular, the PHI post treatment reduced current at the grain boundaries, facilitated an electron barrier, and reduced trap state density, indicating suppression of leakage pathways and charge recombination, thus passivating the grain boundaries. As a result, a significant enhancement in power conversion efficiency to 20.6% was obtained for the PHI-treated perovskite device in comparison to a control device with 17.4%.

High flammability, susceptibility to unstable interfacial reactions and lithium dendrite growth make currently employed liquid electrolyte systems in lithium batteries prone to severe safety concerns. Replacing the liquid electrolytes by solid-state versions is believed to be the ultimate solution to address the safety issues. Many research efforts have been dedicated to find solid-state electrolytes with excellent ionic conductivity comparable to that of the liquid counterparts and tremendous success has been achieved, especially with ceramic sulfide-based and oxide-based solid-state electrolytes. However, another major constraint inhibiting the practical development of such solid-state batteries is the solid–solid interfaces. This review summarizes the notable approaches that have been implemented to address the interface incompatibilities of ceramic solid-state electrolytes with battery electrodes. The focus will be on interfaces of sulfide and oxide solid electrolytes with both cathodes and metallic lithium anodes.

Electric double-layer capacitor (EDLC), as one type of supercapacitor, holds great promises for fast-charging energy storage devices but suffers from limited specific capacitance. The design and development of high performance EDLC-type carbon materials with the effective synergistic effect of high conductivity, tailored porous structure, and high surface area still remain challenging. Here, we report a novel hierarchical porous carbon with a combination of highly conductive electronic pathways and rich ionic storage units in three-dimensional network morphology, leading to high specific capacitance of EDLC. Specifically, by facile hydrothermal synthesis and carbonization, the carbon electrode derived from metal-organic framework and polymer fibers, exhibits extremely high specific capacitance of ∼ 385 F g−1 at 0.1 A g−1 and can still maintain capacitance of 303 F g−1 at 10 A g−1. The high electrochemical performance can be attributed to the rich network of micro and mesoporous structures for electrolyte transport and ion adsorption as well as highly conductive electronic pathways inside the electrodes. The assembled EDLC thus delivers a high energy density of 10.51 Wh kg−1 and a power density of 5.454 kW kg−1 at the current density of 10 A g−1 in the aqueous electrolyte. Hence, the present study is expected to open a promising route to developing porous materials for high-performance energy devices.

Being a direct and wide bandgap semiconductor, zinc oxide is a suitable material for various optoelectronic applications. These applications require tuning and controlling over the electrical and optical properties of zinc oxide films. In this work, zinc oxide thin films were prepared by a solution method that led to oriented crystal growth along (002) plane. The zinc oxide thin films were treated with oxygen, hydrogen, and nitrogen plasmas. The films were characterized to reveal the effects of plasma treatments on transmittance, crystallinity, carrier density, carrier mobility, and electrical resistivity. Oxygen plasma treatment improved the crystallinity of the zinc oxide thin film without affecting the film's transmittance. Hydrogen plasma treatments were found very effective in improving the electrical conductivity sacrificing the film's transmittance. Nitrogen plasma treatment led to improved electrical conductivity without compromising the crystallinity and optical transmittance. Sequential oxygen, ...