# Fullerene-decorated PdCo nano-resistor network hydrogen sensors with sub-second response and parts-per-billion detection at room temperature

## TL;DR

A new hydrogen sensor uses fullerene-decorated nanostructures to detect hydrogen quickly and at very low concentrations, even at room temperature.

## Contribution

The sensor combines nanostructuring, alloying, and surface engineering to achieve sub-second response and parts-per-billion detection.

## Key findings

- The sensor achieves a response time of 0.40 ± 0.06 s across 1–100 mbar H2.
- It detects 40 ppb H2 with a signal-to-noise ratio of 10 at room temperature.
- A PMMA topcoat improves stability and selectivity under high humidity and gas interference.

## Abstract

Hydrogen detection with rapid response and ultra-low detection limits remains a critical challenge for safety and energy applications. Here, we report a fullerene-decorated PdCo nano-resistor network sensor that integrates nanostructuring, alloying, and surface-engineering approaches. The C60 layer enhances sensor performance by increasing the surface-to-volume ratio, enabling fast hydrogen diffusion, relieving mechanical stress during cycling, and guiding nanostructure morphology. Our composite device (20 nm C60/3 nm Teflon AF/5 nm Pd63Co37/30 nm Teflon AF) achieves a response time of 0.40 ± 0.06 s across 1–100 mbar H2 and detects 40 ppb H2 with a signal-to-noise ratio of 10 at room temperature. A poly(methyl methacrylate) (PMMA) topcoat further improves cycling stability and selectivity under 90% relative humidity and interfering gases. This design provides a scalable approach and opens the door to future adaptation of porous carbon-based frameworks and polymeric interlayers to realize robust, high-performance hydrogen sensors for real-world applications.

Researchers have developed a fullerene-decorated PdCo nano-resistor network sensor that achieves fast hydrogen detection time of 0.40 seconds at 0.1% H2 and a detection limit of 40 ppb at room temperature.