2 research outputs found
Cu Microbelt Network Embedded in Colorless Polyimide Substrate: Flexible Heater Platform with High Optical Transparency and Superior Mechanical Stability
Metal nanowires have
been considered as essential components for flexible transparent conducting
electrodes (TCEs) with high transparency and low sheet resistance.
However, large surface roughness and high interwire junction resistance
limit the practical use of metal wires as TCEs. Here, we report Cu
microbelt network (Cu MBN) with coalescence junction and low surface
roughness for next-generation flexible TCEs. In particular, the unique
embedded structure of Cu MBN in colorless polyimide (cPI) film was
achieved to reduce the surface roughness as well as enhance mechanical
stability. The TCEs using junction-free Cu MBN embedded in cPI exhibited
excellent mechanical stability up to 100 000 bending cycles,
high transparency of 95.18%, and a low sheet resistance of 6.25 Ω
sq<sup>–1</sup>. Highly robust Cu MBN-embedded cPI-based TCE
showed outstanding flexible heater performance, i.e., high saturation
temperature (120 °C) at very low voltage (2.3 V), owing to the
high thermal stability of cPI and excellent thermal conductivity of
the Cu MBN
Selective Diagnosis of Diabetes Using Pt-Functionalized WO<sub>3</sub> Hemitube Networks As a Sensing Layer of Acetone in Exhaled Breath
Thin-walled WO<sub>3</sub> hemitubes and catalytic Pt-functionalized
WO<sub>3</sub> hemitubes were synthesized via a polymeric fiber-templating
route and used as exhaled breath sensing layers for potential diagnosis
of halitosis and diabetes through the detection of H<sub>2</sub>S
and CH<sub>3</sub>COCH<sub>3</sub>, respectively. Pt-functionalized
WO<sub>3</sub> hemitubes with wall thickness of 60 nm exhibited superior
acetone sensitivity (<i>R</i><sub>air</sub>/<i>R</i><sub>gas</sub> = 4.11 at 2 ppm) with negligible H<sub>2</sub>S response,
and pristine WO<sub>3</sub> hemitubes showed a 4.90-fold sensitivity
toward H<sub>2</sub>S with minimal acetone-sensing characteristics.
The detection limit (<i>R</i><sub>air</sub>/<i>R</i><sub>gas</sub>) of the fabricated sensors with Pt-functionalized
WO<sub>3</sub> hemitubes was 1.31 for acetone of 120 ppb, and pristine
WO<sub>3</sub> hemitubes showed a gas response of 1.23 at 120 ppb
of H<sub>2</sub>S. Long-term stability tests revealed that the remarkable
selectivity has been maintained after aging for 7 months in air. The
superior cross-sensitivity and response to H<sub>2</sub>S and acetone
gas offer a potential platform for application in diabetes and halitosis
diagnosis