Confinement preparation of Au nanoparticles embedded in ZIF-67-derived N-doped porous carbon for high-performance detection of hydrazine in liquid/gas phase

Abstract Two kinds of usage environments need to be considered for development of hydrazine sensor: the detection of hydrazine in liquid phase and the detection of hydrazine gas in air environment. Here, Au nanoparticles-embedded N-doped porous carbon anchored on reduced graphene oxide (AuNPs@NPC-rGO) nanosheet has been creatively constructed by a confinement preparation process in the frame structure of zeolitic imidazolate framework-67 (ZIF-67). Such ternary hybrid material exhibits good sensitivity for the detection of harmful hydrazine in liquid/gas phase. First, an electrochemical sensor based on AuNPs@NPC-rGO modified glassy carbon electrode (AuNPs@NPC-rGO/GCE) has been established for detection of hydrazine in liquid phase, leading to the linear detection range from 0.05 to 1.00 μM and the detection limit of 9.6 nM. Second, a practical electrochemical gas sensor based on AuNPs@NPC-rGO has been assembled for the detection of hydrazine gas in air environment. Such gas sensor shows the detection limit of 1.8 ppm with fast response/recovery. Those advantages of the electrochemical sensors based on AuNPs@NPC-rGO can be attributed to the key design element of sensing material with structural and compositional advantages leading to the synergy of AuNPs, NPC and rGO.