Synthesis and characterization of Pt–Pd nanoparticles with core-shell morphology: Nucleation and overgrowth of the Pd shells on the as-prepared and defined Pt seeds

A large detectable-range, high-response and fast-response resistivity hydrogen sensor based on Pt/Pd core–shell hybrid with graphene

“…5(a). The core-shell arrangement of the Pd and Pt might facilitate the synergistic effect and subsequently enhanced the catalytic activity of the Pt/Pd core-shell [6][7][8][9]. The adsorption of hydrogen molecules at the interface of the core-shell boundary of Pt/Pd nanoparticles plays the most important role in enhancing H 2 sensing properties.…”

“…The adsorption of hydrogen molecules at the interface of the core-shell boundary of Pt/Pd nanoparticles plays the most important role in enhancing H 2 sensing properties. This also provides an opportunity to energize the highly efficient functional materials for hydrogen storage using bimetallic Pt/Pd [6][7][8][9]11,12]. The sensing mechanism of H 2 sensor based on Pd-Gr is well known [5,10,21,25], in this case a Pt shell with good H 2 dissociation properties lets H 2 pass through and interact with the Pd in the core.…”

“…In addition, both the Pt and Pd catalysts exhibit very a good catalytic activity and selectivity toward hydrogen. It has already been reported that the Pt-Pd core-shell is excellent for H 2 detection, in which the possible enhancement might be facilitated due to the synergetic interplay between the bifunctional core-shell configuration, a large surfaceto-volume ratio and quantum size [6][7][8][9]. According to our previous work [10], Pd nanoparticles (NPs) expand in volume during H 2 absorption/desorption which cause hysteresis behavior in resistivity H 2 sensors.…”

“…In spite of having huge advantages of Pt-based catalysts in H 2 sensing, a high cost of Pt material is crucial. Whereas, the core-shell structure could probably be an excellent method to solve this critical issue, in which the use of Pt as shell can significantly reduce the Pt-loading amount [6][7][8][9]. In addition, both the Pt and Pd catalysts exhibit very a good catalytic activity and selectivity toward hydrogen.…”

“…By coating the Pt shell out of Pd NPs, it can compress the Pd expansion and thus reduce the hysteresis in a sensor. In addition, Pt shell growth on a Pd core can create a huge imperfection at the interface of the core-shell boundary of Pt/Pd NPs, which plays the most important role for enhancing the sensitivity of an H 2 sensor [6][7][8][9]11,12].…”