Sub-second and ppm-level optical sensing of hydrogen using templated control of nano-hydride geometry and composition

Hoang Mai Luong,Tyler Guin,George Keefe Larsen,Tho Duc Nguyen,Minh Thien Pham,Richa Pokharel Madhogaria,Manh-Huong Phan

doi:10.1038/s41467-021-22697-w

Abstract

The use of hydrogen as a clean and renewable alternative to fossil fuels requires a suite of flammability mitigating technologies, particularly robust sensors for hydrogen leak detection and concentration monitoring. To this end, we have developed a class of lightweight optical hydrogen sensors based on a metasurface of Pd nano-patchy particle arrays, which fulfills the increasing requirements of a safe hydrogen fuel sensing system with no risk of sparking. The structure of the optical sensor is readily nano-engineered to yield extraordinarily rapid response to hydrogen gas (<3 s at 1 mbar H2) with a high degree of accuracy (<5%). By incorporating 20% Ag, Au or Co, the sensing performances of the Pd-alloy sensor are significantly enhanced, especially for the Pd80Co20 sensor whose optical response time at 1 mbar of H2 is just ~0.85 s, while preserving the excellent accuracy (<2.5%), limit of detection (2.5 ppm), and robustness against aging, temperature, and interfering gases. The superior performance of our sensor places it among the fastest and most sensitive optical hydrogen sensors.

Highlights

The use of hydrogen as a clean and renewable alternative to fossil fuels requires a suite of flammability mitigating technologies, robust sensors for hydrogen leak detection and concentration monitoring
The fabrication scheme and nanoarchitecture of an optical hydrogen sensor based on a hexagonal array of Pd hemispherical NPs are depicted in Fig. 1a
The designed structure consists of NP arrays on top of hexagonal closed-packed nanosphere monolayer, which is confirmed by Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS)

Summary

Introduction

The use of hydrogen as a clean and renewable alternative to fossil fuels requires a suite of flammability mitigating technologies, robust sensors for hydrogen leak detection and concentration monitoring. The origin of this acceleration could be the reduction of the apparent activation energy for hydrogen sorption due to combination with Ag51, change in morphology to well-separated islands (Supplementary Fig. S10), and due to a decrease in abrupt volume expansion occurring in a smaller mixed phase region, as observed in the narrow hysteresis[52], both leading to a significant increment of hydrogen permeability in Pd80Ag2053.

Results

Conclusion