High response and moisture resistance hydrogen sensors based on sandwich-structured PtSnx-rGO-SnO2 nanocomposites

Currently, semiconductor sensors typically require high operating temperatures (> 200 ?) to detect H-2, which increases energy consumption and safety hazards. This work uses PtSnx to modify rGO-SnO2 nanocomposites to reduce the operating temperature and improve moisture resistance. PtSnx-rGO-SnO2 nanocomposites are synthesized by a simple reflow reaction and have ppm-level H(2 )sensing performance at 175 C with good moisture resistance. The PtSnx-rGO-SnO2 nanocomposite has a thickness of-20 nm. Spherical PtSnx nanoparticles and capsule-shaped SnO2 nanoparticles were grown on the rGO surface. The spherical PtSnx nanoparticles are-15 nm in diameter and the capsule-shaped SnO2 nanoparticles are-5 nm in diameter and-10 nm in length. The phase of PtSnx intermetallic compound varied as the Pt/Sn molar ratio increases. The 0.5 % PtSn2-rGO-SnO2 nanocomposites exhibited the highest response of 20.25 to 500 ppm H-2 at the optimal operating temperature of 175 ? with a short response/recovery times of 1 s/17 s. The 0.5 % PtSn2-rGO-SnO2 nanocomposites also had excellent moisture resistance, reproducibility, and long-term stability. This work reveals that PtSnx-rGO-SnO2 nanocomposites are a promising sensing material for high-performance H-2 detection.

Automated summary

This study successfully reduced the operating temperature and improved moisture resistance of H2 sensors by using PtSnx modified rGO-SnO2 nanocomposites. The nanocomposites exhibited ppm-level H2 sensing performance at 175°C and showed good moisture resistance, reproducibility, and long-term stability. The research suggests that PtSnx-rGO-SnO2 nanocomposites may be a promising material for high-performance H2 detection.