Broadband dielectric spectroscopy for monitoring temperature-dependent chloride ion motion in BiOCl plates

The dielectric properties and electrical conduction mechanism of bismuth oxychloride (BiOCl) plates synthesized using chloramine-T as the chloride ion source were investigated. Thermally-activated structure rebuilding was monitored using broadband dielectric spectroscopy, which showed that the onset temperature of this process was 283 K. This rebuilding was related to the introduction of free chloride ions into [Bi2O2]2+ layers and their growth, which increased the intensity of the (101) diffraction peak. The electrical conductivity and dielectric permittivity were related to the movement of chloride ions between plates (in the low-frequency region), the interplanar motion of Cl− ions at higher frequencies, vibrations of these ions, and charge carrier hopping at frequencies above 10 kHz. The influence of the free chloride ion concentration on the electrical conductivity was also described. Structure rebuilding was associated with a lower concentration of free chloride ions, which significantly decreased the conductivity. According to the analysis, the BiOCl plate conductivity was related to the movement of Cl− ions, not electrons.

Temperature Effect of Nano-Structure Rebuilding on Removal of DWS mc-Si Marks by Ag/Cu MACE Process and Solar Cell

The absence of an effective texturing technique for diamond-wire sawn multi-crystalline silicon (DWS mc-Si) solar cells has hindered commercial upgrading from traditional multi-wire slurry sawn silicon (MWSS mc-Si) solar cells. In this work, we present a novel method for the removal of diamond-wire-sawn marks in a multi-crystalline silicon wafer based on metal assisted chemical etching process with Cu/Ag dual elements and nano-structure rebuilding (NSR) treatment to make a uniform inverted pyramid textured structure. The temperature effect of NSR solution was systematically analyzed. It was found that the size of the inverted pyramid structure and the reflectance became larger with the increase of the NSR treatment temperature. Furthermore, the prepared unique inverted pyramid structure not only benefited light trapping, but also effectively removed the saw-marks of the wafer at the same time. The highest efficiency of 19.77% was obtained in solar cells with an inverted pyramid structure (edge length of 600 nm) fabricated by NSR treatment at 50 °C for 360 s, while its average reflectance was 16.50% at a 400–900 nm wavelength range.

Current Research: Selected Historic Caddo Allen Phase Vessels from the Deshazo Site (41NA13/27) on Bayou Loco, Nacogdoches County, Texas

Continuing with the on-going study of ancestral Caddo ceramic vessels from East Texas Caddo sites, I document three ceramic vessels and a fourth ceramic vessel section from excavations at the Deshazo site (41NA13/27) by The University of Texas at Austin (UT) in 1975-1976. The Deshazo site is the best studied Allen phase settlement in East Texas, and the archaeological investigations there indicates it was a small centralized hamlet of an affiliated group with a series of circular structures and an associated household or family cemetery. Most sites of the Allen phase were apparently occupied for only short periods of time, perhaps an average of 20 to 40 years, based on an analysis of structure rebuilding episodes at the Deshazo site.