Fast responding hydrogen gas sensors using platinum nanoparticle modified microchannels and ionic liquids
MetadataShow full item record
Funding and Sponsorship
© 2019 Elsevier B.V.
From a safety perspective, it is vital to have fast responding gas sensors for toxic and explosive gases in the event of a gas leak. Amperometric gas sensors have been developed for such a purpose, but their response times are often relatively slow – on the order of 50 seconds or more. In this work, we have developed sensors for hydrogen gas that demonstrate ultra-fast response times. The sensor consists of an array of gold microchannel electrodes, electrodeposited with platinum nanoparticles (PtNPs)to enable hydrogen electroactivity. Very thin layers (∼9 μm)of room temperature ionic liquids (RTILs)result in an extremely fast response time of only 2 s, significantly faster than the other conventional electrodes examined (unmodified Pt electrode, and PtNP modified Au electrode). The RTIL layer in the microchannels is much thinner than the channel length, showing an interesting yet complex diffusion pattern and characteristic thin-layer behavior. At short times (e.g. on the timescale of cyclic voltammetry), the oxidation current is smaller and steady-state in nature, compared to macrodisk electrodes. At longer times (e.g. using long-term chronoamperometry), the diffusion layer is large for all surfaces and extends to the liquid/gas phase boundary, where the gas is continuously replenished from the flowing gas stream. Thus, the current response is the largest on the microchannel electrode, resulting in the highest sensitivity and lowest limit of detection for hydrogen. These microchannel electrodes appear to be highly promising surfaces for the ultrafast detection of hydrogen gas, particularly at relevant concentrations close to, or below, the lower explosive limit of 4 vol-% H2.
Showing items related by title, author, creator and subject.
Ionic Liquid-Based Microchannels for Highly Sensitive and Fast Amperometric Detection of Toxic GasesGe, M.; Hussain, G.; Hibbert, D.; Silvester, Debbie; Zhao, C. (2018)Ionic liquid (IL)-based microchannels sensors have been fabricated and employed for the detection of toxic ammonia (NH3) and hydrogen chloride (HCl) gases, with enhanced sensitivity and response times compared to conventional ...
Thin films of poly(vinylidene fluoride-: Co -hexafluoropropylene)-ionic liquid mixtures as amperometric gas sensing materials for oxygen and ammoniaLee, Juni ; Hussain, Ghulam; López-Salas, N.; Macfarlane, D.R.; Silvester-Dean, Debbie (2020)© The Royal Society of Chemistry 2020. Gas sensors are important devices used to monitor the type and amount of gas present. Amperometric gas sensors-based on measuring the current upon an applied potential-have been ...
Formation and characteristics of glucose oligomers during the hydrolysis of cellulose in hot-compressed waterYu, Yun (2009)Energy production from fossil fuels results in significant carbon dioxide emission, which is a key contributor to global warming and the problems related to climate change. Biomass is recognized as an important part of ...