Catalytically activated quantum-size Pt/Pd bimetallic core–shell nanoparticles decorated on ZnO nanorod clusters for accelerated hydrogen gas detection

Surface functionalization of ZnO:Ag columnar thin films with AgAu and AgPt bimetallic alloy nanoparticles as an efficient pathway for highly sensitive gas discrimination and early hazard detection in batteries

“…20 A number of studies have demonstrated that the addition of Pt NPs to different nano-and microstructures of metal oxides can greatly enhance the response to H 2 gas. 20,21,[64][65][66] The Pt NPs may provide more active sites than any other noble metal for the adsorption and catalytic dissociation of oxygen species and H 2 molecules. 20,66 During the sensing process, the spillover and oxidation of hydrogen molecules by the adsorbed oxygen species (see eqn (1)) located near the AgPt bimetallic NPs, explains the high response to H 2 gas.…”

“…19 Fan et al prepared ZnO loaded with PtAu bimetallic NPs, which showed high sensitivity to hydrogen down to the ppm-level, even at room temperature, 20 whereas Hassan et al decorated ZnO nanorods with PtPd bimetallic core-shell NPs for accelerated hydrogen gas detection. 21 Thus, it is crucially important to develop a technological approach which can control alloyed NP properties 15 and to investigate the gas sensing performance of decorated nanocomposites comprising micro-and nanostructured semiconducting oxides and bimetallic NPs. The Ag-based alloys, such as the bimetallic AgPt and AgAu NPs, are of particular interest due to the synergistic effect between the noble metal components, which makes them appealing for surfaceenhanced Raman spectroscopy (SERS) as well as for applications in photocatalysis and sensing.…”

Amorphous Pd-assisted H2 detection of ZnO nanorod gas sensor with enhanced sensitivity and stability

“…The increment in operating temperature slightly lowered the initial resistance of ZnO NRs owing to increased carrier mobility; meanwhile, the sensing response was significantly improved. The sensing response at 80 °C (28,000 %) was 3.5 times that (7,950 %) measured at 20 o C because high operating temperature was boosting the catalytic activity of Pd for H2 cleavage and adsorption [36].…”

“…Therefore, metal oxides composited with the noble metal show a remarkable resistance change to H2 gas exposure. Diverse approaches have been attempted for H2 gas sensors by combining ZnO and Pd [24,36]. Va rious Pd nanostructures have been introduced to enhance the catalytic effect [37][38][39].…”

“…The response and recovery times are defined as the required time to approach 90 % of Smax during the H2 exposure and 10 % of Smax during the recovery, respectively [31,35] In general, metal oxide conductivity changes depending on the amount of chemisorbed oxygens (Mechanism Ⅰ, Fig. S8) [24,25,36]. The Pd nanoparticles act as catalysts for splitting O2 or H2 molecules.…”