Pt nanoparticles stabilized within MOF derivative on inverse opal ZnO for acetone prediction

Abstract

We report a surface anchoring strategy for encapsulating Pt nanoparticles into MOF derivative cavities on inverse opal (IO) ZnO to enhance the sensing properties of metal oxide semiconducting gas sensors. This approach offers significant advantages over existing methods which are limited in synthetic modes and stability. Through in-situ growing ZIF-8 derivative (ZD) onto IO-ZnO, we achieve effective confinement and stabilization of Pt nanoparticles in small size and remarkable catalytic activity as confirmed by CO-TPR. Meanwhile, in-situ growth of ZD supply abundant adsorption sites for gas sensing as verified by acetone-TPR. The sensing material, IO-Pt@ZD/ZnO, comprising Pt nanoparticles encapsulated in IO-ZnO and confined in ZD is prepared for acetone sensor, which exhibits highly sensitivity (S = 36.4 vs. 100 ppm) and robust repeatability (130 cycles at 275 °C for 50 days). Meanwhile, Deep Neural Networks are applied to predict acetone concentration in moisture ambience from an individual sensor (Mean Square Error = 0.05 %). This work establishes a promising prospect for rational construction of metal oxide semiconducting combined with noble metal nanoparticles for highly catalytic activity, robust stability, and outstanding sensitivity in gas sensor application.