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.

Energy for a sustainable future motivates today's R&D, enabling technologies such as smart consumer electronics, electric vehicles, and smart grids. These technologies demand the use of batteries. Sunlight, an abundant clean source of energy, can alleviate the energy limits of batteries, while batteries can address photovoltaic intermittency. This perspective paper focuses on advancing concepts in PV-battery system design while providing critical discussion, review, and prospect. Reports on discrete and integrated PV-battery designs are discussed. Three key technical challenges, namely energy density, efficiency, and stability, toward further advancement of integrated PV-battery systems are discussed. We present a perspective on opportunities and future directions, highlighting key strategies on developing such PV-battery systems. Key focus should be on the development of innovative designs that incorporates high-capacity, efficient, and stable materials, emphasizing the demonstration of practical viability of such integrated PV-battery systems. Drive for New Technologies for a Sustainable Future Today's mass consumers heavily rely on energy technologies and their ongoing development. Three key technologies that encompass the present energy scenario are smart consumer electronics, electric vehicles, and smart grids. Smart electronics depend on capacity-limited batteries, making recharging a necessity. Continuing advancement in consumer electronics demands additional battery power. With the mobility delivered to users by modern technology, frequent recharging of the electronics using a wired connection seems inhibiting. Solar or photovoltaics (PV) provide the convenience for battery charging, owing to the high available power density of 100 mW cm À2 in sunlight outdoors.

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Interface engineering is critical to the development of highly efficient perovskite solar cells. Here, urea treatment of hole transport layer (e.g., poly(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS)) is reported to effectively tune its morphology, conductivity, and work function for improving the efficiency and stability of inverted MAPbI 3 perovskite solar cells (PSCs). This treatment has significantly increased MAPbI 3 photovoltaic performance to 18.8% for the urea treated PEDOT:PSS PSCs from 14.4% for pristine PEDOT:PSS devices. The use of urea controls phase separation between PEDOT and PSS segments, leading to the formation of a unique fiber-shaped PEDOT:PSS film morphology with well-organized charge transport pathways for improved conductivity from 0.2 S cm −1 for pristine PEDOT:PSS to 12.75 S cm −1 for 5 wt% urea treated PEDOT:PSS. The urea-treatment also addresses a general challenge associated with the acidic nature of PEDOT:PSS, leading to a much improved ambient stability of PSCs. In addition, the device hysteresis is significantly minimized by optimizing the urea content in the treatment.order to overcome the reactivity issue of the acidic PEDOT:PSS with the plastic substrates. Therefore, we expect this technology to be expanded for addressing the stability and performance issues of perovskite solar cells.

3860 mAh g −1 ), low redox potential (−3.04 V vs standard hydrogen electrode) and high capability to be coupled with high-voltage and/or high-capacity cathode materials. [1] However, the practical application of Li as an anode in rechargeable lithium batteries is still hindered by the uncontrollable growth of Li dendrites, low Coulombic efficiency (CE), and limited cycle life. [2] Numerous efforts have been made to address these issues. One of the strategies focuses on the design of suitable electrolytes by optimizing the concentration, [3] adding additives and fillers, [4] engineering highmodulus solid electrolytes and polymer electrolytes. [5] These advanced electrolytes are expected to have excellent electrochemical stability on the Li electrode and higher Young's modulus to resist the dendrite growth. [6] Further, developing stable host materials and nanostructured scaffolds to accommodate Li during the plating process has been employed to address the issues of large volume changes during lithium plating/stripping. [7] Recently, developing an artificial interfacial layer between the electrolyte and Li metal electrode has attracted tremendous attention in lithium metal batteries (LMBs). The interfacial layer can prevent side reactions, enable fast Li-ion diffusion, and suppress the Li dendrite growth for the efficient operation of Li metal anode. The side reactions and interfacial instability of Li metal lead to significant consumption of electrolyte. As a result, the resistance of the Li metal cell increases that leads to overpotential and ultimately short cell lifespan. Previous studies showed that various ceramics such as SiO 2 , TiO 2 , SnO 2 , and Al 2 O 3 are very promising interfacial layers to buffer the volumetric expansion of the anode. [8] Such ceramic layers are able to conduct Li + and block electron transport. [9] Lithiated multiwall carbon nanotubes and multilayered graphene with high mechanical rigidity have been reported as a controlled Li diffusion interface. [10] In addition, glass fibers, silica sandwiched between two separators, and silica@poly(methyl methacrylate) (SiO 2 @PMMA) nanosphere-modified Cu electrode has also been studied. [7c,11] These artificial layers improve wettability toward electrolyte, reduce the concentration of Li ions, and react with growing Li to suppress the dendrites. Organic/inorganic Lithium metal anodes are expected to drive practical applications that require high energy-density storage. However, the direct use of metallic lithium causes safety concerns, low rate capabilities, and poor cycling performance due to unstable solid electrolyte interphase (SEI) and undesired lithium dendrite growth. To address these issues, a radio frequency sputtered graphite-SiO 2 ultrathin bilayer on a Li metal chips is demonstrated, for the first time, as an effective SEI layer. This leads to a dendrite free uniform Li deposition to achieve a stable voltage profile and outstanding long hours plating/stripping compared to the bare Li. Compared to a bare Li anode, the graph...

In recent years, hybrid perovskite solar cells (HPSCs) have received considerable research attention due to their impressive photovoltaic performance and low-temperature solution processing capability. However, there remain challenges related to defect passivation and enhancing the charge carrier dynamics of the perovskites, to further increase the power conversion efficiency of HPSCs. In this work, the use of a novel material, phenylhydrazinium iodide (PHAI), as an additive in MAPbI 3 perovskite for defect minimization and enhancement of the charge carrier dynamics of inverted HPSCs is reported. Incorporation of the PHAI in perovskite precursor solution facilitates controlled crystallization, higher carrier lifetime, as well as less recombination. In addition, PHAI additive treated HPSCs exhibit lower density of filled trap states (10 10 cm −2 ) in perovskite grain boundaries, higher charge carrier mobility (≈11 × 10 −4 cm 2 V −1 s), and enhanced power conversion efficiency (≈18%) that corresponds to a ≈20% improvement in comparison to the pristine devices.

Low-temperature processed inorganic hole transport layer for efficient and stable mixed Pb-Sn low-bandgap perovskite solar cells

8-Hydroxylquinoline (OQ) is demonstrated for the first time as a strong alternative anchoring group porphyrin dyes to improve the long-term stability of solar cells.