Pd₈₀Co₂₀Nanohole Arrays Coated with Poly(methyl methacrylate) for High-Speed Hydrogen Sensing with a Part-per-Billion Detection Limit

Abstract

As hydrogen gas increasingly becomes critical as a carbon-free energy carrier, the demand for robust hydrogen sensors for leak detection and concentration monitor will continue to rise. However, to date, there are no lightweight sensors capable of meeting the required performance metrics for the safe handling of hydrogen. Here, we report an electrical hydrogen gas sensor platform based on a resistance nanonetwork derived from Pd-Co composite hole arrays (CHAs) on a glass substrate, which meets or exceeds these metrics. In optimal nanofabrication conditions, a single poly(methyl methacrylate)(PMMA)-coated CHA nanosensor exhibits a response time (t 80 ) of 1.0 s at the lower flammability limit of H 2 (40 mbar), incredible sensor accuracy (<1% across 5 decades of H 2 pressure), and an extremely low limit of detection (LOD) of <10 ppb at room temperature. Remarkably, these nanosensors are extremely inert against CO and O 2 gas interference and display robust long-term stability in air, suffering no loss of performance over 2 months. Additionally, we demonstrate that the unique nanomorphology renders the sensors insensitive to operation voltage/current with diminutive power requirement (∼2 nW) and applied magnetic field (up to 3 kOe), a crucial metric for leak detection and concentration control.

Unlocking Predictive Capability and Enhancing Sensing Performances of Plasmonic Hydrogen Sensors via Phase Space Reconstruction and Convolutional Neural Networks

“…The LOD is established at an SNR = 3 and measured as 16 Pa. The relationship between the SNR and P can be fitted well using the function SNR = aP b (Figure f), ,− achieving a coefficient of determination ( R 2 ) of 0.98. In addition, common low-frequency drift was observed (Figure e), representing slow systematic changes over time, possibly due to thermal fluctuations, instrumental drift, and baseline adjustments, all of which are standard considerations in the interpretation of the spectroscopic data.…”

Plasmonic Nanostructure Lattices for High‐Performance Sensing

“…[146] The PTFE coating shows poor protection from deactivation by other gases, such as CO and NO 2 , while the poly (methylmethacrylate) (PMMA) cladding layer has excellent H 2 selectivity to other gases and protection for plasmonic NPs. [171,172] Pd 70 Au 30 @PTFE/PMMA tandem coating sensors were constructed to combine the properties of both PTFE and PMMA, and the device shows similar detection performance to that of PTFE coating alone and can operate in ambient conditions for four months without deactivation. Additionally, the polymer layer can also act as a medium to transfer the information of gas specie and concentration into RI changes through chemical or physical processes and followed by detecting through plasmonic responses.…”

Highly Sensitive Detection of Hydrogen Gas Using Nanoporous Composites of Halloysite Nanotubes and Palladium

“…Based on this unique reaction between Pd and H 2 , many optical and resistive H 2 detectors have been recently developed and reported in the literature. − ,, However, optical detectors usually involve complex and expensive optoelectronic instruments to operate, while resistive detectors are attractive due to their high sensitivity, low power-consumption, less complex supporting electronics, and high compactness. Despite the efforts made by researchers to address various issues in resistive detector development, ,− enhancing the detector sensitivity or lowering its limit of detection (LOD) remains a significant ongoing effort. For instance, Xu et al developed a hydrogen detector using an ultrathin Pd film produced from vacuum evaporation.…”