Rational Integration of SnMOF/SnO2 Hybrid on TiO2 Nanotube Arrays: An Effective Strategy for Accelerating Formaldehyde Sensing Performance at Room Temperature

作     者：He, Zhen-Kun Zhao, Jiahui Li, Keke Zhao, Junjian He, Haoxuan Gao, Zhida Song, Yan-Yan 

作者机构：Northeastern Univ Coll Sci Shenyang 110819 Peoples R China 

出 版 物：《ACS SENSORS》 (ACS Sensors)

年 卷 期：2023年第8卷第11期

页      面：4189-4197页

核心收录：

基　　金：National Natural Science Foundation of China [22074013, 22204016, 22374015] National Natural Science Foundation of China [N2105018] Fundamental Research Funds for the Central Universities 

主　　题：SnMOF/SnO2 hybrid spaced TiO2 NTA preconcentration room temperature formaldehyde sensor 

摘      要：Formaldehyde is ubiquitously found in the environment, meaning that real-time monitoring of formaldehyde, particularly indoors, can have a significant impact on human health. However, the performance of commercially available interdigital electrode-based sensors is a compromise between active material loading and steric hindrance. In this work, a spaced TiO2 nanotube array (NTA) was exploited as a scaffold and electron collector in a formaldehyde sensor for the first time. A Sn-based metal-organic framework was successfully decorated on the inside and outside of TiO2 nanotube walls by a facile solvothermal decoration strategy. This was followed by regulated calcination, which successfully integrated the preconcentration effect of a porous Sn-based metal-organic framework (SnMOF) structure and highly active SnO2 nanocrystals into the spaced TiO2 NTA to form a Schottky heterojunction-type gas sensor. This SnMOF/SnO2@TiO2 NTA sensor achieved a high room-temperature formaldehyde response (1.7 at 6 ppm) with a fast response (4.0 s) and recovery (2.5 s) times. This work provides a new platform for preparing alternatives to interdigital electrode-based sensors and offers an effective strategy for achieving target preconcentrations for gas sensing processes. The as-prepared SnMOF/SnO2@TiO2 NTA sensor demonstrated excellent sensitivity, stability, reproducibility, flexibility, and convenience, showing excellent potential as a miniaturized device for medical diagnosis, environmental monitoring, and other intelligent sensing systems.