Hot-Carrier Extraction Prevailing over Multiple-Exciton Generation in Two-Dimensional Semiconductor Heterostructures.

Multiple-exciton generation (MEG) represents an effective strategy to break the Shockley-Queisser (SQ) limit, thereby enhancing the efficiency of photon-to-electron conversion. Here, we investigate MEG in monolayer MoTe, with an energy threshold of 2.22 eV (∼2.

An Ultrasensitive and Broad-Spectrum MoS Photodetector with Extrinsic Response Using Surrounding Homojunction.

As unique building blocks for advancing optoelectronics, 2D semiconducting transition metal dichalcogenides have garnered significant attention. However, most previously reported MoS photodetectors respond only to visible light with limited absorption, resulting in a narrow spectral response and low sensitivity. Here, a surrounding homojunction MoS photodetector featuring localized p-type nitrogen plasma doping on the surface of n-type MoS while preserving a high-mobility underlying channel for rapid carrier transport is engineered.

Two-Dimensional Perovskite (PEA)PbI Two-Color Blue-Green Photodetector.

Perovskite materials have been widely used to fabricate solar cells, laser diodes and other photodevices, owing to the advantage of high absorption coefficient, long carrier life and shallow defect energy levels. However, due to easy hydrolysis, it is difficult to fabricate perovskite micro-nano devices. Herein, we developed a water-free device fabrication technology and fabricated a two-dimensional (CHCHNH)PbI ((PEA)PbI) two-color blue-green light detector, which exhibits high detection performance under the illumination of two-color lasers (λ = 460 nm, 532 nm).

Ultrafast and Highly Sensitive Dual-Channel FET Photodetector Based on a Two-Dimensional MoS Homojunction.

Two-dimensional transition metal dichalcogenide-based phototransistors have been intensively studied in recent years due to their high detection rate and flexibility. However, the photogating effect, usually appearing in the devices, leads to a poor transient photoresponse, which slows down the imaging rate of the camera based on the devices. Here, we demonstrate a dual-channel two-dimensional field-effect phototransistor composed of a vertical molybdenum disulfide (MoS) p-n homojunction as the sensitizing channel layer.

Bio-Separated and Gate-Free 2D MoS Biosensor Array for Ultrasensitive Detection of BRCA1.

2D molybdenum disulfide (MoS)-based thin film transistors are widely used in biosensing, and many efforts have been made to improve the detection limit and linear range. However, in addition to the complexity of device technology and biological modification, the compatibility of the physical device with biological solutions and device reusability have rarely been considered. Herein, we designed and synthesized an array of MoS by employing a simple-patterned chemical vapor deposition growth method and meanwhile exploited a one-step biomodification in a sensing pad based on DNA tetrahedron probes to form a bio-separated sensing part.

Flexible Transparent Heat Mirror for Thermal Applications.

Transparent heat mirrors have been attracting a great deal of interest in the last few decades due to their broad applications, which range from solar thermal convection to energy-saving. Here, we present a flexible Polyethylene terephthalate/Ag-doped Indium tin oxide/Polydimethylsiloxane (PAIP) thin film that exhibits high transmittance in visible range and low emissivity in the thermal infrared region. Experimental results show that the temperature of the sample can be as high as 108 °C, which is ~23 °C higher than that of a blackbody control sample under the same solar radiation.

Bending Experiment and Mechanical Properties Analysis of Composite Sandwich Laminated Box Beams.

The failure modes, ultimate load, stiffness performance, and their influencing factors of a composite sandwich laminated box beam under three-point bending load are studied by an experiment, finite element model, and analytical method. The three-point bending experiment was carried out on three different core composite sandwich laminated box beams, and the failure modes and bearing capacity were studied. With the use of composite progressive damage analysis and the core elastoplastic constitutive model, the finite element model of the composite sandwich laminated box beam was established, and the three-point bending failure process and failure modes were analyzed.

Anomalous thermoelectricity in strained Bi2Te3 films.

Bi2Te3-based alloys have been intensively used for thermoelectric coolers and generators due to their high Seebeck coefficient S. So far, efforts to improve the S have been made mostly on changing the structures and components. Herein, we demonstrate an anomalous thermoelectricity in strained Bi2Te3 films, i.

An investigation of exciton behavior in type-II self-assembled GaSb/GaAs quantum dots.

We report the investigation of exciton dynamics in type-II self-assembled GaSb/GaAs quantum dots. The GaSb/GaAs quantum dots (QDs) were grown using a modified liquid phase epitaxy technique. Statistical size distributions of the uncapped QDs were investigated experimentally by field-emission scanning electron microscopy (SEM) and atomic force microscopy (AFM), and theoretically by an eight-band k  ·  p calculation, which demonstrated a dissolution effect.