Unveiling Cu Nanoparticles Formed During Li Deposition in Anode-Free Batteries.

Developing high-energy-density Li metal batteries is essential for sustainable progress, necessitating in-depth studies of complex battery reactions. The presence of metallic Cu impurities detrimentally impacts battery performance, leading to issues such as self-discharging and internal soft short-circuit. Nevertheless, their formation mechanism and structural characteristics have not been revealed clearly.

Enhancing UV-C Photoelectron Lifetimes for Avalanche-like Photocurrents in Carbon-Doped BiOCl Nanosheets.

Interlayer electric fields in two-dimensional (2D) materials create photoelectron protecting barriers useful to mitigate electron-hole recombination. However, tuning the interlayer electric field remains challenging. Here, carbon-doped BiOCl (C:BiOCl) nanosheets are synthesized using a gas phase protocol, and n-type carriers are acquired as confirmed by the transconductance polarity of nanosheet field effect transistors.

Elastic Properties of High-Symmetry SbO Cage-Molecular Crystal.

The cubic-phase antimony trioxide (α-SbO) is a room-temperature stable molecular crystal, composed of cage-like tetraantimony hexoxide (SbO) molecules. Despite its versatile functionality, the van der Waals (vdW) bond-dominated nanomechanics is still unclear. Here, the bending plate-like linear behaviors of high-quality α-SbO nanoflakes were observed using the nanoindentation method.

Inorganic Low Cage-molecular Crystals.

For the interlayer dielectric in microelectronics, light element compounds are preferably accepted due to less electronic polarization. Here, the nontrivial dielectric nature of the SbO cage-molecular crystal, known as α-antimony trioxide (α-SbO), is reported. The gas-phase synthesized α-SbO nanoflakes are of high crystal quality, from which the abnormal local admittance responses were revealed by scanning microwave impedance microscopy (sMIM).

Simultaneous Thermoelectric Property Measurement and Incoherent Phonon Transport in Holey Silicon.

Block copolymer patterned holey silicon (HS) was successfully integrated into a microdevice for simultaneous measurements of Seebeck coefficient, electrical conductivity, and thermal conductivity of the same HS microribbon. These fully integrated HS microdevices provided excellent platforms for the systematic investigation of thermoelectric transport properties tailored by the dimensions of the periodic hole array, that is, neck and pitch size, and the doping concentrations. Specifically, thermoelectric transport properties of HS with a neck size in the range of 16-34 nm and a fixed pitch size of 60 nm were characterized, and a clear neck size dependency was shown in the doping range of 3.

Elastic properties of van der Waals epitaxy grown bismuth telluride 2D nanosheets.

Bismuth telluride (Bi2Te3) two-dimensional (2D) nanosheets prepared by van der Waals epitaxy were successfully detached, transferred, and suspended for nano-indentation measurements to be performed on freestanding circular nanosheets. The Young's modulus acquired by fitting linear elastic behaviors of 26 samples (thickness: 5-14 nm) is only 11.7-25.

Mechanism of bismuth telluride exfoliation in an ionic liquid solvent.

Bismuth telluride (Bi2Te3) is a well-known thermoelectric material that has a layered crystal structure. Exfoliating Bi2Te3 to produce two-dimensional (2D) nanosheets is extremely important because the exfoliated nanosheets possess unique properties, which can potentially revolutionize several material technologies such as thermoelectrics, heterogeneous catalysts, and infrared detectors. In this work, ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) is used to exfoliate Bi2Te3 nanoplatelets.

Selective adsorption of bismuth telluride nanoplatelets through electrostatic attraction.

We demonstrate a facile technique to assemble solution phase-synthesized bismuth telluride (Bi2Te3) nanoplatelets into arrays of micropatterns. Aminosilane self-assembled monolayers (SAMs) are printed on silicon dioxide (SiO2) substrates using microcontact printing (μCP). The SAM printed surfaces are terminated with amine-groups allowing Bi2Te3 nanoplatelet selective adsorption by electrostatic attraction.

High quantum efficiency of band-edge emission from ZnO nanowires.

External quantum efficiency (EQE) of photoluminescence as high as 20% from isolated ZnO nanowires were measured at room temperature. The EQE was found to be highly dependent on photoexcitation density, which underscores the importance of uniform optical excitation during the EQE measurement. An integrating sphere coupled to a microscopic imaging system was used in this work, which enabled the EQE measurement on isolated ZnO nanowires.

Multinozzle emitter arrays for nanoelectrospray mass spectrometry.

Mass spectrometry (MS) is the enabling technology for proteomics and metabolomics. However, dramatic improvements in both sensitivity and throughput are still required to achieve routine MS-based single cell proteomics and metabolomics. Here, we report the silicon-based monolithic multinozzle emitter array (MEA) and demonstrate its proof-of-principle applications in high-sensitivity and high-throughput nanoelectrospray mass spectrometry.

Holey silicon as an efficient thermoelectric material.

This work investigated the thermoelectric properties of thin silicon membranes that have been decorated with high density of nanoscopic holes. These "holey silicon" (HS) structures were fabricated by either nanosphere or block-copolymer lithography, both of which are scalable for practical device application. By reducing the pitch of the hexagonal holey pattern down to 55 nm with 35% porosity, the thermal conductivity of HS is consistently reduced by 2 orders of magnitude and approaches the amorphous limit.

Advances in Hydrogen, Carbon Dioxide, and Hydrocarbon Gas Sensor Technology Using GaN and ZnO-Based Devices.

In this paper, we review our recent results in developing gas sensors for hydrogen using various device structures, including ZnO nanowires and GaN High Electron Mobility Transistors (HEMTs). ZnO nanowires are particularly interesting because they have a large surface area to volume ratio, which will improve sensitivity, and because they operate at low current levels, will have low power requirements in a sensor module. GaN-based devices offer the advantage of the HEMT structure, high temperature operation, and simple integration with existing fabrication technology and sensing systems.

The control of cell adhesion and viability by zinc oxide nanorods.

The ability to control the behavior of cells that interact with implanted biomaterials is desirable for the success of implanted devices such as biosensors or drug delivery devices. There is a need to develop materials that can limit the adhesion and viability of cells on implanted biomaterials. In this study, we investigated the use of zinc oxide (ZnO) nanorods for modulating the adhesion and viability of NIH 3T3 fibroblasts, umbilical vein endothelial cells, and capillary endothelial cells.

Carbon nanotube films for room temperature hydrogen sensing.

Thin, uniform, single-walled carbon nanotube films, made by a simple filtration process, subsequently coated with palladium, are shown to be promising detectors of hydrogen. The films detected hydrogen with relative responses of 20% at 100 ppm and 40% at 500 ppm concentrations. Most of the initial film conductance was recovered within 30 s by exposing the samples to air.