Pressure Coupled Lanthanide Ion Doping to Enhance Optical Properties in BaTiO₃

Abstract

Self‐trapped excitons (STEs) typically give broadband photoluminescence emission with a large Stokes shift, which is important for the enhancement of the optical properties of materials. Here, low‐dimensional La‐doped BaTiO3 nanocrystals with defects are prepared using supercritical CO2 (SC CO2). The generation of the STEs is facilitated by doping La3+ ions and introducing CO2 pressure, which effectively enhance the luminescence intensity of BaTiO3. This discovery shows that the La ion doping concentration can modulate the photoluminescence of BaTiO3 nanocrystals under pressure. This work deepens the understanding of the influence of rare‐earth‐doped luminescent materials under pressure and provides insight to improve the capabilities of optical devices.

Supercritical CH3OH-Triggered Isotype Heterojunction and Groups in g-C3N4 for Enhanced Photocatalytic H2 Evolution

“…Supercritical fluids (SCFs) display unique physicochemical properties such as low viscosity, zero surface tension, and high diffusivity . The SCF technology has received much attention in the fields of nanomaterial synthesis ranging from scientific research to industrial application. − Owing to the solvation behavior and enhanced mass transfer ability of SCFs, a homogeneous reaction environment could be formed by dissolving chemicals (including metal precursor, organic solvent, surfactant, redox agent, and so on) in SCFs, realizing a rapid SCF-assisted hydrothermal/solvothermal synthesis of metals, metal hydroxides, metal oxides, metal sulfides, metal–organic frameworks, and composites. − On the other hand, structure tuning of nanomaterials such as exfoliation, − surface reduction and oxidation, phase engineering, − and elemental doping − could be realized by the post-treatment strategy utilizing SCFs. Among numerous SCFs, supercritical H 2 O (ScH 2 O) and supercritical CO 2 (ScCO 2 ) are extensively employed in the preparation and modification of nanomaterials. , Recently, supercritical alcohols have become another important SCF following ScH 2 O and ScCO 2 .…”