Sonication‐Assisted Palladium Nanogaps in a Capacitive Structure: A Tunable and Reliable Solution for Sensitive Hydrogen Monitoring
Year: 2025
Type: article
Abstract: Pd nanogap hydrogen sensors rapidly and selectively detect H 2 through hydrogenation‐induced volumetric expansion of the Pd lattice. However, this type of resistive sensor faces challenges in ensuring reliability due to the difficulty of precisely controlling nanogaps formed within the potential conduction paths. Herein, a novel H 2 sensor is proposed that utilizes a capacitive mechanism to substantially improve both sensitivity and reliability. Simple ultrasonication is employed to create Pd seed cracks, which evolve into uniform nanogap networks following initial phase transitions (α‐PdH → β‐PdH). In the Pd/PDMS/Doped‐Si system, capacitive response driven by the area change of the upper electrode accurately reflects real‐time nanogap behavior in response to H 2 , producing stable signals within a defined range of values. The initial crack density, adjustable by varying the sonication time, allows for customizable gap sizes and detection ranges, achieving sub‐20 nm gaps and an ultra‐low detection limit of 3 ppm. Repeatability tests using 300 ppm H 2 over 50 cycles demonstrate exceptional durability and signal stability at low concentrations, surpassing previous Pd nanogap sensors. This capacitive sensor provides a reliable and adaptable solution for H 2 detection, marking a significant advancement toward commercializing Pd nanogap sensors.
Source: Advanced Functional Materials
Authors: Sang‐kil Lee, Joonho Lee, Jiwoo Hong, Seyoung Park, Eugene Cho, Seunghyun Lee, Keunhyung Lee, Keunhyung Lee, Hyun‐Sook Lee, Kyu Hyoung Lee, Kyu Hyoung Lee, Wooyoung Lee
Institution: Yonsei University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,790
Funders: National Research Foundation, Ministry of Trade, Industry and Energy, National Research Foundation of Korea, Ministry of the Interior and Safety, Ministry of Science and ICT, South Korea, National Fire Agency, Commercializations Promotion Agency for R and D Outcomes, Division of Materials Research
OpenAlex ID: W4411904421