MOF-on-MOF nanoarchitecturing of Fe2O3@ZnFe2O4 radial-heterospindles towards multifaceted superiorities for acetone detection

Rational integration of multifunctions is an emerging strategy to develop novel chemiresistor nano platforms with superior sensing properties. Herein, a stepwise synthesis strategy is developed to assemble two MOFs with huge mismatch into MOF-on-MOF heterojunction, which was nanoarchitectured into Fe2O3@ZnFe2O4 radialheterospindles. The Fe2O3@ZnFe2O4 heterospindles exhibited outstanding selective acetone detection with multifaceted superiorities, such as high response, low limit of detection, fast response and recovery time, and good linearity in responses with a wide concentration window. An in-depth discussion revealed that such multifaceted sensing characters can be attributed to the distinct radial-heterostructure which proffer synergetic effects in the unimpeded gas diffusion with mesoporous sensing nanoarchitecture, favored interfacial charge transport in radial heterojunction, abundant active adsorption/reaction sites by rich oxygen vacancies, and exponential/efficient tuning of sensor resistance with barrier height. This synthetic strategy here may offer a new opportunity for fabricating dual-to-multi MOFs-based advanced nanostructures towards practical chemiresistor nanoplatforms with favorable multifaceted superiorities.

Automated summary

In this study, a stepwise synthesis strategy was developed to assemble two mismatched MOFs into a heterojunction, creating a superior chemiresistor nano platform. The platform showed excellent selective acetone detection with high response, low limit of detection, fast response and recovery time, and good linearity in responses. These multifaceted sensing properties can be attributed to the distinct radial-heterostructure, mesoporous sensing nanoarchitecture, abundant active adsorption/reaction sites, and efficient tuning of sensor resistance.