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In recent years, metal compound‐based heterojunctions have received increasing attention from researchers as a candidate anode for lithium/sodium‐ion batteries, because heterojunction anodes possess unique interfaces, robust architectures, and synergistic effects, thus promoting Li/Na ions storage and accelerating ions/electrons transport. Exhilaratingly, the development of heterostructures has made rapid progress in the field of energy storage, greatly encouraging the industrialization of high energy and power density Li/Na ion batteries. However, there are few in‐detail and in‐depth reviews on the energy storage mechanism, synthesis routes, characterization methods and electrochemical performance of metal compound‐based heterojunction anodes. Herein, a deeper understanding of the correlation between the building blocks of heterojunctions and their enhanced electrochemical behaviors are summarized. Furthermore, various synthesis routes and characterization methods for heterostructure anodes are roundly reviewed. Finally, challenges and perspectives of heterojunction anodes in energy storage are presented in this work. [ABSTRACT FROM AUTHOR]

Here we report for the first time a van der Waals (vdW) heterostructure formed from an individual single crystal SbSI whisker and individual PbI2 flake for photodetection. Benefiting from the millimeter-sized whisker and flake, we take advantage of the flexibility of operation and vdW junction interface between SbSI and PbI2. This mixed-dimensional heterostructure is used as an optoelectronics platform due to the larger light-harvesting cross section than the individual material. It generates photocurrent to broaden the spectral response range. The two-dimensional (2D) material acts as a current collector, while the single crystal whisker material acts as a current channel. Compared with the individual SbSI device, the vdW heterojunction device can achieve a lower dark current. As a result, our SbSI–PbI2 photodetector exhibits a responsivity of up to 26.3 mA W−1 and shows a fast response speed of ∼12 ms. Large-area growth and scalable approaches lead to an efficient transfer strategy and heterostructure assembly. These investigations will broaden our fundamental knowledge of vdW heterostructures. This mixed-dimensional vdW heterostructure opens new opportunities for basic research of micro/nano-optoelectronics. [ABSTRACT FROM AUTHOR]

Abstract: Single-crystalline ZnSe/Ge bi-axial heterostructural nanowires were grown via a simple one-step thermal evaporation of mixed ZnSe and Ge powders. The heterostructure nanowires have uniform diameter of 200nm and their length ranges are from several tens to several hundreds of micrometers. Both the zinc-blende ZnSe and diamond-like cubic Ge sub-nanowires in the heterostructures are single crystalline, and grow along the [111] direction. The sub-nanowires of ZnSe and Ge, with ideal interfaces along the growth orientation, have diameters of 120 and 80nm, respectively. The experimental evidence suggests that the bi-axial nanowires are formed via a co-growth mechanism. The vibrating property of the nanowire was investigated by Raman spectroscopy at room-temperature. [ABSTRACT FROM AUTHOR]

Single-crystalline Zn/ZnS coaxial nanocables were fabricated through thermal reduction of ZnS using graphite powder at elevated temperatures. Energy dispersive x-ray analysis of the as-fabricated samples indicated that the nanowires were composed of Zn and S only. Transmission-electron-microscopic study of the nanowires revealed that they had core/sheath contrast, suggesting a Zn core/ZnS sheath heterostructure. Epitaxial relationship was observed between the Zn and the ZnS. The possible formation mechanisms of such nanocables are discussed. [ABSTRACT FROM AUTHOR]

Tetrapod-shaped heterostructured nanocrystals are promising materials in photoelectric devices due to their special morphology and structure. In this paper, CdSe/CdTe heterostructured nano-tetrapods with type II band alignment were synthesized by a simple chemical method in solution. High-resolution transmission electron microscopy (HRTEM) images show that CdSe/CdTe heterostructures are composed by CdSe tetrapod with CdTe nanorods epitaxially grown on the four arms. No core–shell heterostructures were observed. UV–visible absorption spectroscopy (UV–vis) shows that the absorption peak of CdSe/CdTe heterostructure tetrapod nanocrystals is red-shift comparing with that of CdSe tetrapod-shaped nanocrystals. It is also weaker and broader than that of nano-tetrapods. The room-temperature photoluminescence (PL) intensity of heterostructures is much weaker than that of CdSe nano-tetrapods. It is believed that it is due to the spatial separation of electrons and holes in heterostructures. [ABSTRACT FROM AUTHOR]