Transition metal selenides have been widely used in alkali metal ion batteries owing to their high specific capacities and low cost. However, their reaction kinetics and structural stability are usually poor during cycling, along with ambiguous differences in Li/Na/K-storage behaviors. Herein, it is revealed that ZnSe possesses better Na + -diffusion kinetics (including lower diffusion barrier, smaller activation energy, and higher diffusion coefficients) in comparison with Li + and K + , as evidenced by theoretical calculations and electrochemical studies. The architectural designs of ZnSe-based anode, including nitrogen-doped carbon (N,C) and 3D ordered hierarchical pores (3DOHP) to form a 3DOHP ZnSe@N,C hybrid combined with regulating solid electrolyte interphase (SEI), significantly enhance Na + reaction kinetics and accommodate volume changes. The resulting 3DOHP ZnSe@N,C electrodes exhibit outstanding rate capability and good cycling stability (241.6 mAh g −1 in sodium-ion batteries (SIBs) at 10 A g −1 after 800 cycles), originating from improved electrical conductivity and shortened ion diffusion paths, accompanied by ultrathin and stable SEI with less Na 2 CO 3 /NaF in organic components and boosted Na 2 Se adsorption as sodiation. Moreover, the Na-storage mechanism in 3DOHP ZnSe@N,C hybrid is further revealed by in situ studies. Accordingly, this study provides a new perspective for designing high-performance electrode materials for SIBs.

Combining both 1D geometry and the features of hybrid perovskite materials, perovskite micro/nanowires have recently attracted particular attention for a variety of optoelectronic device applications. Herein, by taking advantage of the strong built‐in potential induced by asymmetric contact with varied work functions, highly sensitive visible photodetectors based on a CH3NH3PbI3 microwire array that display pronounced photovoltaic activities are reported. These photodetectors afford the capability to work without an external power supply. A representative detector with Au/Ag electrodes achieves a reasonable responsivity of 161.1 mA W−1 with a fast response speed of 13.8/16.1 µs under 520 nm illumination at zero bias. In addition, such a device is also characterized by an ultralow dark current of tens of femtoamps, enabling a high specific detectivity of 1.3 × 1012 Jones. Furthermore, a flexible photodetector is successfully prepared, which shows comparable photoresponse performance and outstanding flexibility and bending durability. Given the good device performance and simple device geometry, the present self‐driven photodetectors hold great promise for future highly sensitive and low‐energy‐consumption photodetection systems.

Photodetection in the solar‐blind deep‐ultraviolet (DUV) regime (200–280 nm) has received significant attention for its many critical applications in military and civil areas. In this study, a vapor–solid synthesis technique for catalyst‐free growth of single‐crystalline β‐Ga2O3 nanowires is developed. A photodetector made of the nanowires is highly sensitive to 265 nm DUV illumination with excellent photoresponse performance. The performance parameters including Ilight/Idark ratio, responsivity, specific detectivity and response speed can attain ≈103, ≈233 A W−1, ≈8.16 × 1012 Jones, and 0.48/0.04 s, respectively. Additionally, the detector has an abrupt response cutoff wavelength at ≈290 nm with a reasonable DUV/visible (250–405 nm) rejection ratio exceeding 102. It is also found that the device can operate properly at a large applied bias of 200 V with the responsivity being enhanced to as high as ≈1680 A W−1. Moreover, such a nanowires‐based photodetector can function as a DUV light image sensor with a reasonable spatial resolution. Holding the above advantages, the present DUV photodetector based on catalyst‐free grown β‐Ga2O3 nanowires possesses huge possibility for application in future DUV optoelectronics.

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We report on the synthesis of layered γ-In2Se3 nanofilm for broadband photodetector and near infrared light image sensing applications.