This study proposes a reliable and self-powered hydrogen (H2) gas sensor composed of a chemo-mechanically operating nanostructured film and photovoltaic cell. Specifically, the nanostructured film has a configuration in which an asymmetrically coated palladium (Pd) film is coated on a periodic polyurethane acrylate (PUA) nanograting. The asymmetric Pd nanostructures, optimized by a finite element method simulation, swell upon reacting with H2 and thereby bend the PUA nanograting, changing the amount of transmitted light and the current output of the photovoltaic cell. Since the degree of warping is determined by the concentration of H2 gas, a wide concentration range of H2 (0.1-4.0%) can be detected by measuring the self-generated electrical current of the photovoltaic cell without external power. The normalized output current changes are â1.5%, â2.8%, â3.5%, â5.0%, â21.5%, and 25.3% when the concentrations of H2 gas are 0.1%, 0.5%, 1.0%, 1.6%, 2%, and 4%, respectively. Moreover, because Pd is highly chemically reactive to H2 and also because there is no electrical current applied through Pd, the proposed sensor can avoid device failure due to the breakage of the Pd sensing material, resulting in high reliability, and can show high selectivity against various gases such as carbon monoxide, hydrogen sulfide, nitrogen dioxide, and water vapor. Finally, using only ambient visible light, the sensor was modularized to produce an alarm in the presence of H2 gas, verifying a potential always-on H2 gas monitoring application.
|Number of pages||10|
|Publication status||Published - 2020 Dec 22|
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (no. 2015R1A5A1037668). This research was also supported by Nano·Material Technology Development Program through NRF funded by the Ministry of Science, ICT, and Future Planning (no. 2009-0082580). J.R. acknowledges the POSTECH-Samsung Electronics research center funded by Samsung Electronics Co., Ltd. The EDA tool was supported by the IC Design Education Center (IDEC), Republic of Korea.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physics and Astronomy(all)