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A photodetector based on 2D non‐layered materials can easily utilize the photogating effect to achieve considerable photogain, but at the cost of response speed. Here, a rationally designed tunneling heterojunction fabricated by vertical stacking of non‐layered In2S3 and Te flakes is studied systematically. The Te/In2S3 heterojunctions possess type‐II band alignment and can transfer to type‐I or type‐III depending on the electric field applied, allowing for tunable tunneling of the photoinduced carriers. The Te/In2S3 tunneling heterojunction exhibits a reverse rectification ratio exceeding 104, an ultralow forward current of 10−12 A, and a current on/off ratio over 105. A photodetector based on the heterojunctions shows an ultrahigh photoresponsivity of 146 A W−1 in the visible range. Furthermore, the devices exhibit a response time of 5 ms, which is two and four orders of magnitude faster than that of its constituent In2S3 and Te. The simultaneously improved photocurrent and response speed are attributed to the direct tunneling of the photoinduced carriers, as well as a combined mechanism of photoconductive and photogating effects. In addition, the photodetector exhibits a clear photovoltaic effect, which can work in a self‐powered mode.

High-quality Li4Ti5O12/N-doped carbon (LTO/N-C) nanotube arrays on a conductive substrate are fabricated via a new ALD-assisted method for lithium ion battery applications. The designed LTO/N-C nanotube arrays show very impressive high-rate capacity (153 mA h g−1 at 5C) and stable capacity: 98% retention after 6000 cycles at 40C.

Recent years have witnessed major advances in development of massive nonlayer structured ultrathin materials, providing great enrichment to the 2D nanomaterial family. The intriguing physical and chemical properties brought by nonlayered nanomaterials have attracted tremendous research interest. In this work, a systematica study of the optical properties of 2D nonlayered β‐diindium trisulfide (β‐In2S3) is reported. The thickness‐dependent photoluminescence (PL), Raman spectra, and absorption property are measured for ultrathin β‐In2S3 flakes and found distinguished from its bulk counterpart. These peculiar features originate from the superficial indium oxide in ultrathin β‐In2S3, as revealed by low‐temperature PL and X‐ray photoelectron spectroscopy measurement. The Raman vibration modes are identified by Raman spectra measurements combined with calculations using density functional theory. Importantly, the tetragonal β‐In2S3 flakes exhibit strong in‐plane anisotropic Raman response under the angle‐resolved polarized Raman spectroscopy measurements. The results in this paper provide an in‐depth understanding of the emerging 2D nonlayered material In2S3 and pave a fundamental step for its potential applications in future electronics and optoelectronics.

As an emerging 2D nonlayered material, natural defective β-In2S3 nanosheets have drawn attention because of their unique defective structure and broad optical detection range. Stacking n-type In2S3 with other p-type 2D materials can produce an atomically sharp interface with van der Waals interaction, which may lead to high performance in (opto)­electronics. In this study, we fabricated a van der Waals heterostructure composed of In2S3 and graphene via the dry transfer method. Scanning Kelvin probe force microscopy revealed a significant potential difference at the interface of the heterostructure, thereby endowing it with good diode characteristics. The back-gate field effect transistor based on the graphene/In2S3 heterostructure exhibited excellent gate-tunable current-rectifying characteristic with n-type semiconductor behavior. A photodetector based on the graphene/In2S3 heterostructure showed excellent response to visible light. Particularly, an ultrahigh responsivity of 795 A/W and an external quantum efficiency of 2440% are recorded under the illumination of 405 nm light and can be further increased to 8570 A/W and 26 200% with a positive gate voltage of 60 V. The excellent optical responsive performance is attributed to the synergy of photoconductive and photogating effects. These intriguing results suggest that the graphene/In2S3 heterostructure has prospective applications in future electronic and optoelectronic devices.

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In this paper, flower-like MoS 2 nanosheets microspheres were successfully synthesized by low temperature hydrothermal process using the precursors of sodium molybdate (Na 2 MoO 4 Á2H 2 O), thiourea (SC(NH 2 ) 2 ), oxalic acid (C 2 H 2 O 4 Á2H 2 O) and de-ionized water. The effects of oxalic acid concentrations and growth time on the morphology and crystallographic structure of MoS 2 nanosheets microspheres were investigated. The morphology, crystallographic structure, chemical composition of the flower-like MoS 2 nanosheets microspheres were investigated by using scanning electron microscope, X-ray diffraction, Raman spectrum, high resolution transmission electron-microscopy, and X-ray photoelectron spectroscopy, respectively. It is revealed that MoS 2 powders are composed of large, uniform flower-like microspheres, which are formed by several nanosheets gathering together perpendicular to the spherical surface. And the nanosheets are poly-crystallized hexagonal phase. The experiment results also show that the oxalic acid concentration in the precursors plays a key role on the diameter and crystalline of MoS 2 nanosheets microspheres. The formation mechanism of flower-like MoS 2 nanosheets microspheres was discussed.

The elemental two-dimensional (2D) tellurium (Te) possesses fascinating properties such as high mobility, strong anisotropy and strong infrared response, which show great potential for various applications. However, the fabrication of...