Electrospinning is a versatile technique for the construction of microfibrous and nanofibrous structures with considerable potential in applications ranging from textile manufacturing to tissue engineering scaffolds. In the simplest form, electrospinning uses a high voltage of tens of thousands volts to draw out ultrafine polymer fibers over a large distance. However, the high voltage limits the flexible combination of material selection, deposition substrate, and control of patterns. Prior studies show that by performing electrospinning with a well-defined "near-field" condition, the operation voltage can be decreased to the kilovolt range, and further enable more precise patterning of fibril structures on a planar surface. In this work, by using solution dependent "initiators", we demonstrate a further lowering of voltage with an ultralow voltage continuous electrospinning patterning (LEP) technique, which reduces the applied voltage threshold to as low as 50 V, simultaneously permitting direct fiber patterning. The versatility of LEP is shown using a wide range of combination of polymer and solvent systems for thermoplastics and biopolymers. Novel functionalities are also incorporated when a low voltage mode is used in place of a high voltage mode, such as direct printing of living bacteria; the construction of suspended single fibers and membrane networks. The LEP technique reported here should open up new avenues in the patterning of bioelements and free-form nano- to microscale fibrous structures.

Photodetectors (PDs) based on perovskite nanowires are among the most promising next‐generation photodetection technologies; however, their poor long‐term stability is the biggest challenge limiting their commercial application. Herein, an ionic liquid, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4), is incorporated as an additive into methylammonium lead triiodide (MAPbI3) nanowires; this not only effectively passivates defects to inhibit perovskite degradation but also leads to the formation of nanochannels, enabling fast charge transfer. As a result, the long‐term stability and performance of MAPbI3 nanowires are considerably improved. The detectivity, linear detection range, and noise equivalent power of the MAPbI3 nanowire PD reach 2.06 × 1013 Jones, 160 dB, and 1.38 × 10−15 W Hz−1/2, respectively, comparable to the highest performance of perovskite nanowire PDs reported to date. Moreover, the unencapsulated PD can maintain 100% of its initial performance after being exposed to an open‐air environment for more than 5000 h, establishing it as the most stable perovskite nanowire PD reported to date. Notably, the PD exhibits improved diffuse reflection imaging ability when compared with commercial silicon photodiode S2386. This study provides a new strategy for constructing sensitive, stable, and flexible perovskite PDs and will accelerate their commercial application in the future.

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The alkaline zinc-based batteries with high energy density are becoming a research hotspot. However, the poor cycle stability and low-rate performance limit their wide application. Herein, ultra-thin CoNiO2 nanosheet with rich oxygen defects anchored on the vertically arranged Ni nanotube arrays (Od-CNO@Ni NTs) is used as a positive material for rechargeable alkaline Ni–Zn batteries. As the highly uniform Ni nanotube arrays provide a fast electron/ion transport path and abundant active sites, the Od-CNO@Ni NTs electrode delivers excellent capacity (432.7 mAh g−1) and rate capability (218.3 mAh g−1 at 60 A g−1). Moreover, our Od-CNO@Ni NTs//Zn battery is capable of an ultra-long lifespan (93.0% of initial capacity after 5000 cycles), extremely high energy density of 547.5 Wh kg−1 and power density of 92.9 kW kg−1 (based on the mass of cathode active substance). Meanwhile, the theoretical calculations reveal that the oxygen defects can enhance the interaction between electrode surface and electrolyte ions, contributing to higher capacity. This work opens a reasonable idea for the development of ultra-durable, ultra-fast, and high-energy Ni–Zn battery."Image missing"