Effects of poisoning gases on and restoration of PdCuSi metallic glass in a capacitive MEMS hydrogen sensor

High-Performance Nanostructured Palladium-Based Hydrogen Sensors—Current Limitations and Strategies for Their Mitigation

“…A specific shortcoming of the handful of studies that do investigate the effects of sensor deactivation/poisoning is that, except for the work by Hayashi et al, none of the tests executed in the works presented in Table follows the protocol suggested by ISO 26142, since all studies applied premixed H 2 and poisoning gases. The ISO 26142 protocol, however, suggests exposure to poisoning species prior to a H 2 pulse to test the poisoning effect, since this is closer to a scenario in a real setting .…”

Enhancement of Interfacial Hydrogen Interactions with Nanoporous Gold-Containing Metallic Glass

“…New-generation Pd-based nanomaterials are promising candidates to enhance the efficiency of hydrogen interactions, thus providing green alternatives for nanoscale energy applications. Among these, Pd-metallic glasses (MGs) have recently garnered significant recognition in a variety of energy applications, including hydrogen storage and release, − hydrogen evolution reaction (HER), − hydrogen oxidation reaction in fuel cells, methanol/ethanol electrooxidation, − glucose sensors, MEMS hydrogen sensor, − and hydrogen permeation membranes. − The grain-free structure of metallic glasses, along with the presence of free volume between atomic clusters, are advantages of Pd-MGs over polycrystalline Pd (alloys) in terms of hydrogen storage and release as well as electrochemical stability in long-term use. ,,,, …”

Optimization of the Composition of PdAuCu Ternary Alloy Nanoparticles for Plasmonic Hydrogen Sensing

“…7,11 Interestingly, the corresponding research also has revealed that alloying with Au reduces the hydrogen sorption apparent activation energies, which leads to faster sensor response/recovery compared to pure Pd. 12 Similarly, it has been demonstrated that also a second limitation of pure Pd can be mitigated by alloying since the addition of Cu to Pd significantly improves the resistance against sensor poisoning and deactivation by CO. 8,10 Following this line, in a proof-of-principle fashion, we have recently shown that these two strategies can be combined in a ternary PdAuCu alloy for plasmonic optical hydrogen detection. 10 However, in such a ternary system, the introduction of Cu not only mitigates the CO poisoning effect but also quite dramatically reduces sensor sensitivity due to the shift of the two-phase equilibrium plateau to higher hydrogen partial pressures.…”

“…Such nanoplasmonic hydrogen sensors rely on visible light-induced collective and coherent excitation of electrons in hydride-forming metal nanoparticlesthe LSPRas a signal transducing mechanism, where the hydrogen sorption and hydride formation processes give rise to a sizable optical contrast, which is proportional to the hydrogen concentration in the sensor surroundings . At the same time, despite their excellent selectivity toward hydrogen gas, the performance of pure Pd-based sensors, in general, and of plasmonic solutions, in particular, is hampered by several inherent limitations, such as hysteresis, slow response/recovery times, and proneness to deactivation by poisoning species like CO. − As a consequence, numerous strategies have been developed to minimize the impact of these negative effects and the use of coinage metal-Pd alloys has emerged as one of the most promising directions in this respect. − For example, hydride formation hysteresis can be suppressed by alloying Pd nanoparticles with at least 25 at % Au. , Interestingly, the corresponding research also has revealed that alloying with Au reduces the hydrogen sorption apparent activation energies, which leads to faster sensor response/recovery compared to pure Pd . Similarly, it has been demonstrated that also a second limitation of pure Pd can be mitigated by alloying since the addition of Cu to Pd significantly improves the resistance against sensor poisoning and deactivation by CO. , Following this line, in a proof-of-principle fashion, we have recently shown that these two strategies can be combined in a ternary PdAuCu alloy for plasmonic optical hydrogen detection .…”

“…At the same time, despite their excellent selectivity toward hydrogen gas, the performance of pure Pd-based sensors, in general, and of plasmonic solutions, in particular, is hampered by several inherent limitations, such as hysteresis, slow response/recovery times, and proneness to deactivation by poisoning species like CO. − As a consequence, numerous strategies have been developed to minimize the impact of these negative effects and the use of coinage metal-Pd alloys has emerged as one of the most promising directions in this respect. − For example, hydride formation hysteresis can be suppressed by alloying Pd nanoparticles with at least 25 at % Au. , Interestingly, the corresponding research also has revealed that alloying with Au reduces the hydrogen sorption apparent activation energies, which leads to faster sensor response/recovery compared to pure Pd . Similarly, it has been demonstrated that also a second limitation of pure Pd can be mitigated by alloying since the addition of Cu to Pd significantly improves the resistance against sensor poisoning and deactivation by CO. , Following this line, in a proof-of-principle fashion, we have recently shown that these two strategies can be combined in a ternary PdAuCu alloy for plasmonic optical hydrogen detection . However, in such a ternary system, the introduction of Cu not only mitigates the CO poisoning effect but also quite dramatically reduces sensor sensitivity due to the shift of the two-phase equilibrium plateau to higher hydrogen partial pressures. , Therefore, to optimize the performance of this ternary alloy system for application in plasmonic hydrogen sensors, there is an imminent demand for the systematic optimization of the alloy components with respect to the following three criteria: (i) poisoning/deactivation resistance, (ii) hysteresis suppression, and (iii) sensitivity.…”