Tunable green syngas generation from CO and HO with sunlight as the only energy input.

The carbon-neutral synthesis of syngas from CO and HO powered by solar energy holds grand promise for solving critical issues such as global warming and the energy crisis. Here we report photochemical reduction of CO with HO into syngas using core/shell Au@CrO dual cocatalyst-decorated multistacked InGaN/GaN nanowires (NWs) with sunlight as the only energy input. First-principle density functional theory calculations revealed that Au and CrO are synergetic in deforming the linear CO molecule to a bent state with an O-C-O angle of 116.

A microfluidic field-effect transistor biosensor with rolled-up indium nitride microtubes.

Field-effect-transistor (FET) biosensors capable of rapidly detecting disease-relevant biomarkers have long been considered as a promising tool for point-of-care (POC) diagnosis. Rolled-up nanotechnology, as a batch fabrication strategy for generating three-dimensional (3D) microtubes, has been demonstrated to possess unique advantages for constructing FET biosensors. In this paper, we report a new approach combining the two fascinating technologies, the FET biosensor and the rolled-up microtube, to develop a microfluidic diagnostic biosensor.

Few-Atomic-Layers Iron for Hydrogen Evolution from Water by Photoelectrocatalysis.

The carbon-free production of hydrogen from water splitting holds grand promise for the critical energy and environmental challenges. Herein, few-atomic-layers iron (Fe) anchored on GaN nanowire arrays (NWs) is demonstrated as a highly active hydrogen evolution reaction catalyst, attributing to the spatial confinement and the nitrogen-terminated surface of GaN NWs. Based on density functional theory calculations, the hydrogen adsorption on Fe:GaN NWs is found to exhibit a significantly low free energy of -0.

Decoupling Strategy for Enhanced Syngas Generation from Photoelectrochemical CO Reduction.

Photoelectrochemical CO reduction into syngas (a mixture of CO and H) provides a promising route to mitigate greenhouse gas emissions and store intermittent solar energy into value-added chemicals. Design of photoelectrode with high energy conversion efficiency and controllable syngas composition is of central importance but remains challenging. Herein, we report a decoupling strategy using dual cocatalysts to tackle the challenge based on joint computational and experimental investigations.

An electrically pumped surface-emitting semiconductor green laser.

Surface-emitting semiconductor lasers have been widely used in data communications, sensing, and recently in Face ID and augmented reality glasses. Here, we report the first achievement of an all-epitaxial, distributed Bragg reflector (DBR)-free electrically injected surface-emitting green laser by exploiting the photonic band edge modes formed in dislocation-free gallium nitride nanocrystal arrays, instead of using conventional DBRs. The device operates at ~523 nm and exhibits a threshold current of ~400 A/cm, which is over one order of magnitude lower compared to previously reported blue laser diodes.

Highly efficient binary copper-iron catalyst for photoelectrochemical carbon dioxide reduction toward methane.

A rational design of an electrocatalyst presents a promising avenue for solar fuels synthesis from carbon dioxide (CO) fixation but is extremely challenging. Herein, we use density functional theory calculations to study an inexpensive binary copper-iron catalyst for photoelectrochemical CO reduction toward methane. The calculations of reaction energetics suggest that Cu and Fe in the binary system can work in synergy to significantly deform the linear configuration of CO and reduce the high energy barrier by stabilizing the reaction intermediates, thus spontaneously favoring CO activation and conversion for methane synthesis.

Photodeposition of a conformal metal oxide nanocoating.

A versatile photochemical route is reported to access conformal metal oxide nanocoatings including Cr2O3, Al2O3, ZnO and In2O3 on semiconductor substrates. The Cr2O3 nanocoating can enhance the photoelectrochemical performance of GaN nanowires on a p-n junction Si photoelectrode, which exhibits a benchmark half-cell solar to hydrogen efficiency of 11.8%.

Structural origin of the high-performance light-emitting InGaN/AlGaN quantum disks.

Ternary III-nitride-based nanowires with highly efficient light-emitting properties are essential for a broad range of applications. By using the selective area molecular-beam epitaxy method, InGaN/AlGaN quantum disks (QDs) embedded in hexagonal GaN nanowires were successfully grown. With the help of atomic-scale-resolved transmission electron microscopy and atom probe tomography, atomic ordering and other related structural information, such as crystallography and local chemistry, have been unambiguously revealed to provide unique insights into the exceptionally strong photoluminescence enhancements.