Hybrid halide perovskites emerging as a highly promising class of functional materials for semiconductor optoelectronic applications have drawn great attention from worldwide researchers. In the past few years, prominent nonlinear optical properties have been demonstrated in perovskite bulk structures indicating their bright prospect in the field of nonlinear optics (NLO). Following the surge of 3D perovskites, more recently, the low‐dimensional perovskites (LDPs) materials ranging from two‐, one‐, to zero‐dimension such as quantum‐wells or colloidal nanostructures have displayed unexpectedly attractive NLO response due to the strong quantum confinement, remarkable exciton effect, and structural diversity. In this perspective, the current state of the art is reviewed in the field of NLO for LDP materials. The relationship between confinement effect and NLO is analyzed systematically to give a comprehensive understanding of the function of dimension reduction. Furthermore, future directions and challenges toward the improvement of the NLO in LDP materials are discussed to provide an outlook in this rapidly developing field.

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Although zinc‐based batteries are promising candidates for eco‐friendly and cost‐effective energy storage devices, their performance is severely retarded by dendrite formation. As the simplest zinc compounds, zinc chalcogenides, and halides are individually applied as a Zn protection layer due to high zinc ion conductivity. However, the mixed‐anion compounds are not studied, which constrains the Zn2+ diffusion in single‐anion lattices to their own limits. A heteroanionic zinc ion conductor (ZnyO1−xFx) coating layer is designed by in situ growth method with tunable F content and thickness. Strengthened by F aliovalent doping, the Zn2+ conductivity is enhanced within the wurtzite motif for rapid lattice Zn migration. ZnyO1−xFx also affords zincophilic sites for oriented superficial Zn plating to suppress dendrite growth. Therefore, ZnyO1−xFx‐coated anode exhibits a low overpotential of 20.4 mV for 1000 h cycle life at a plating capacity of 1.0 mA h cm−2 during symmetrical cell test. The MnO2//Zn full battery further proves high stability of 169.7 mA h g−1 for 1000 cycles. This work may enlighten the mixed‐anion tuning for high‐performance Zn‐based energy storage devices.

Multiple ultrashort laser pulses are widely used in optical spectroscopy, optoelectronic manipulation, optical imaging and optical signal processing etc. The laser pulse multiplication, so far, is solely realized by using the optical setups or devices to modify the output laser pulse from the optical gain medium. The employment of these external techniques is because the gain medium itself is incapable of modifying or multiplying the generated laser pulse. Herein, with single femtosecond laser pulse excitation, we achieve the double-pulsed stimulated emission with pulse duration of around 40 ps and pulse interval of around 70 ps from metalhalide perovskite multiple quantum wells. These unique stimulated emissions originate from one fast vertical and the other slow lateral high-efficiency carrier funneling from lowdimensional to high-dimensional quantum wells. Furthermore, such gain medium surprisingly possesses nearly Auger-free stimulated emission. These insights enable us a fresh approach to multiple the ultrashort laser pulse by gain medium.

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MoS2 holds great promise as high‐rate electrode for lithium‐ion batteries since its large interlayer can allow fast lithium diffusion in 3.0–1.0 V. However, the low theoretical capacity (167 mAh g−1) limits its wide application. Here, by fine tuning the lithiation depth of MoS2, we demonstrate that its parent layered structure can be preserved with expanded interlayers while cycling in 3.0–0.6 V. The deeper lithiation and maintained crystalline structure endows commercially micrometer‐sized MoS2 with a capacity of 232 mAh g−1 at 0.05 A g−1 and circa 92 % capacity retention after 1000 cycles at 1.0 A g−1. Moreover, the enlarged interlayers enable MoS2 to release a capacity of 165 mAh g−1 at 5.0 A g−1, which is double the capacity obtained under 3.0–1.0 V at the same rate. Our strategy of controlling the lithiation depth of MoS2 to avoid fracture ushers in new possibilities to enhance the lithium storage of layered transition‐metal dichalcogenides.

High-performance (22.86%) and high-stability (3000 h) perovskite solar cells are obtained by introducing a novel polyfluorinated cation to form a new film structure.

The fundamental understanding of the relationship between the nanostructure of an electrode and its electrochemical performance is crucial for achieving high-performance lithium-ion batteries (LIBs). In this work, the relationship between the nanotubular aspect ratio and electrochemical performance of LIBs is elucidated for the first time. The stirring hydrothermal method was used to control the aspect ratio of viscous titanate nanotubes, which were used to fabricate additive-free TiO 2 -based electrode materials. We found that the battery performance at high charging/discharging rates is dramatically boosted when the aspect ratio is increased, due to the optimization of electronic/ionic transport properties within the electrode materials. The proof-of-concept LIBs comprising nanotubes with an aspect ratio of 265 can retain more than 86 % of their initial capacity over 6000 cycles at a high rate of 30 C. Such devices with supercapacitor-like rate performance and battery-like capacity herald a new paradigm for energy storage systems.The provision of efficient electron and ion transport is a critical issue in developing electrode materials to achieve ultrafast rechargeable LIBs. [1] A prevalent strategy is to design nanostructured electrode materials with high conductivity and short path length, [2] since the diffusion time is proportional to the square of diffusion length and inversely proportional to diffusivity. [2d] Although different nanostructures have been developed to increase the cycle life and electrochemical performance of LIBs at high rates, [3] several features still limit the fundamental understanding of the relationship between LIB performance and nanostructured active materials, [4] owing to the use of polymeric binders [5] and conductive materials [3, 6, 7] in conventional battery construction. One such limitation is that the inhomogeneous blend of the additives and electroactive materials influences the diffusion paths of lithium ions and electrons in the electrode. [8] As a result, it is difficult to model and characterize the actual electrochemical reaction. Another limitation is that the additives, which normally account for the weight and volume increase of the electrode, [8] do not contribute to the actual battery storage performance but greatly alter the overall LIB performance. Therefore, a simple model of an additive-free electrode is required to precisely elucidate the correlation between the actual electrochemical performance and structural properties of the active materials.In a conventional battery system, a polymer binder with the desired viscosity is required to mechanically secure the active materials and additives. However, if the active materials themselves are viscous enough to adhere well on the current collector, the binder is not needed in the battery system. Inspired by the hydrogel-like properties of onedimensional (1D) fibrous structures, [9] we hypothesize that viscous 1D nanostructures may serve as electroactive materials to build battery cells without a binder. In ad...