A low-dimensional-structure vacuum-ultraviolet-sensitive photodetector based on high-quality aluminum nitride (AlN) micro-/nanowires is reported. This work, for the first time, demonstrates that a semiconductor nanostructure can be applied in vacuum-ultraviolet (VUV) photon detection and opens a way for developing diminutive, power-saving, and low-cost VUV materials and sensors that can be potentially applied in geospace sciences and solar-terrestrial physics.

The angle dependence of optical phonon modes of an AlN bulk single crystal from the m-plane (1100) and c-plane (0001) surfaces, respectively, is investigated by polarized Raman spectroscopy in a backscattering configuration at room temperature. Corresponding Raman selection rules are derived according to measured scattering geometries to illustrate the angle dependence. The angle-dependent intensities of phonon modes are discussed and compared to theoretical scattering intensities, yielding the Raman tensor elements of A 1 TO, E 2 2 , E 1 TO, and A 1 LO phonon modes and the relative phase difference between the two complex elements of A 1 TO. Furthermore, the Raman tensor of wurtzite AlN is compared with that of wurtzite ZnO reported in previous work, revealing the intrinsic differences of lattice vibration dynamics between AlN and ZnO.

Harvesting solar energy for artificial photosynthesis is an emerging field in alternative energy research. In this work, the photocatalytic properties of InX(X=S, Se)/transition-metal disulfides (MoS2 and WS2) van der Waals...

An aluminum nitride (AlN) Schottky barrier diode (SBD) was fabricated on a nonpolar AlN crystal grown on tungsten substrate by physical vapor transport. The Ni/Au-AlN SBD features a low ideality factor n of 3.3 and an effective Schottky barrier height (SBH) of 1.05 eV at room temperature. The ideality factor n decreases and the effective SBH increases at high temperatures. The temperature dependences of n and SBH were explained using an inhomogeneous model. A mean SBH of 2.105 eV was obtained for the Ni-AlN Schottky junction from the inhomogeneity analysis of the current-voltage characteristics. An equation in which the parameters have explicit physical meanings in thermionic emission theory is proposed to describe the currentvoltage characteristics of inhomogeneous SBDs. Index Terms-AlN, non-polar, Schottky barrier diode, inhomogeneity, thermionic emission, physical vapor transport.

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Bioinspired artificial visual perception devices with the optical environment‐adaptable function have attracted significant attention for their promising potential in applications like robotics and machine vision. In this regard, a photodetector with in‐sensor adaptability is longed for in terms of complexity, efficiency, and cost. Here, a near‐infrared phototransistor with a benign light irradiance‐adaptability is presented. The phototransistor uses a vertically stacking graphene/lead sulfide quantum dots/graphene heterojunction as the conductive channel. Compared with ordinary lead sulfide quantum dots‐decorated graphene phototransistors, the present device demonstrates a faster photoresponse speed and an abnormal transfer characteristic. The latter characteristic is induced by the gate voltage‐tunable Fermi level in the heterojunction and the abundant electron trap states in the quantum dot film, which jointly results in an intense dependence of the photoresponse on the gate voltage. The dynamic trapping and de‐trapping processes in the quantum dot film enable the inhibition or potentiation of the photoresponse, based on which the photopic or scotopic adaptation behavior of the human retina is successfully mimicked, respectively. By providing an irradiance‐adaptable photodetector with a spectral response beyond visible light, this work should inspire future research on artificial environment‐adaptable perception devices.

Phototransistors In article number 2205679, Peiguang Yan, Zhenhua Sun, and co‐workers report a near‐infrared phototransistor with benign light‐irradiance adaptability using a vertically stacking graphene/lead sulfide quantum dots/graphene heterojunction as the conductive channel. The dynamic trapping and detrapping processes in the quantum dot film enable the inhabitation or potentiation of the photoresponse, based on which the photopic or scotopic adaptation behavior of the human retina is successfully mimicked, respectively.

As a promising candidate in the construction industry, iron-based shape memory alloy (Fe-SMA) has attracted lots of attention in the engineering and metallography communities because of its foreseeable benefits including corrosion resistance, shape recovery capability, excellent plastic deformability, and outstanding fatigue resistance. Pilot applications have proved the feasibility of Fe-SMA as a highly efficient functional material in the construction sector. This paper provides a review of recent developments in research and design practice related to Fe-SMA. The basic mechanical properties are presented and compared with conventional structural steel, and some necessary explanations are given on the metallographic transformation mechanism. Newly emerged applications, such as Fe-SMA-based prestressing/strengthening techniques and seismic-resistant components/devices, are discussed. It is believed that Fe-SMA offers a wide range of applications in the construction industry but there still remains problems to be addressed and areas to be further explored. Some research needs at material-level, component-level, and system-level are highlighted in this paper. With the systematic information provided, this paper not only benefits professionals and researchers who have been working in this area for a long time and wanting to gain an in-depth understanding of the state-of-the-art, but also helps enlighten a wider audience intending to get acquainted with this exciting topic.