Boosting Thermoelectric Performance in Epitaxial GeTe Film/Si by Domain Engineering and Point Defect Control.

This study demonstrates a simultaneous realization of ultralow thermal conductivity and high thermoelectric power factor in epitaxial GeTe thin films/Si substrates by a combination of the interface introduction by domain engineering and the suppression of Ge vacancy generation by point defect control. We formed epitaxial Te-poor GeTe thin films having low-angle grain boundaries with a misorientation angle close to 0° or twin interfaces with a misorientation angle close to 180°. The control of interfaces and point defects gave rise to ultralow lattice thermal conductivity of ∼0.

Optical Resolution Photoacoustic Microscopy With Fast Laser Scanning and Fixed Photoacoustic Detector.

Photoacoustic (PA) imaging is rapidly progressing imaging modality in which very short pulsed laser causes thermal expansion to generate PA signal. In previous PA microscope systems, relatively long time was required for image acquisition because they required mechanical scan of the PA transducer. The objective of the present study is to develop fast laser scanning optical resolution photoacoustic microscopy (OR-PAM) with fixed PA signal detector to realize very high frame rate PA imaging.

Understanding the Colloidal Stability of Nanoparticle-Ligand Complexes: Design, Synthesis, and Structure-Function Relationship Studies of Amphiphilic Small-Molecule Ligands.

For effective application of nanoparticles, their amenability to in-solution processing must be addressed, and stable, homogeneous solvent conditions are required. Although organic ligands have been used as surface-modifying reagents for nanoparticles to increase their colloidal stability and homogeneity in solution, the structure-function relationships of nanoparticle-ligand complexes remain elusive and controversial. Herein, a series of novel amphiphilic small-molecule ligands were designed, synthesized, and applied as surface-modifying reagents for aqueous, transparent TiO and ZrO nanoparticles.