Red to Blue High Electrochromic Contrast and Rapid Switching Poly(3,4-ethylenedioxypyrrole)-Au/Ag Nanocomposite Devices for Smart Windows

High Sensitivity Plasmonic Sensing of Hydrogen over a Broad Dynamic Range Using Catalytic Au-CeO2 Thin Film Nanocomposites

Next-generation gas-sensor technologies are needed for diverse applications including environmental surveillance, occupational safety, and industrial process control. However, the dynamic range using existing sensors is often too narrow to meet demands. In this work, plasmonic films of Au-CeO₂ that detect hydrogen with 0.38% and 60% lower and upper detection limits in an oxygen-free atmosphere experiment are demonstrated. The observed 15 nm peak shift was 4 times stronger versus other plasmonic H₂ sensors. The proposed sensing mechanism that involves H₂ dissociation by Au^δ+ nanoparticles was validated using XPS, kinetics, and Arrhenius studies. Our understanding of this remarkable sensing behavior in oxygen-free conditions opens new horizons for packaging, art conservation, industrial process control, and other applications where conventional oxygen-dependent sensors lack broad dynamic range.

(Gold nanorod core)/(polyaniline shell) plasmonic switches with large plasmon shifts and modulation depths

(Gold nanorod core)/(polyaniline shell) nanostructures are prepared for functioning as active plasmonic switches. The single core/shell nanostructures exhibit a remarkable switching performance, with the modulation depth and scattering peak shift reaching 10 dB and 100 nm, respectively. The nanostructures are also deposited on substrates to form macroscale monolayers with remarkable ensemble plasmonic switching performances.