Zhang Ziling, Ma Junhao, Deng Yu, Ren Yuan, Xie Wenhe, Deng Yonghui, Zou Yidong, Luo Wei
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
ACS Appl Mater Interfaces. 2023 Mar 29;15(12):15721-15731. doi: 10.1021/acsami.2c23108. Epub 2023 Mar 14.
Hydrogen as an important clean energy source with a high energy density has attracted extensive attention in fuel cell vehicles and industrial production. However, considering its flammable and explosive property, gas sensors are desperately desired to efficiently monitor H concentration in practical applications. Herein, a facile polymerization-induced aggregation strategy was proposed to synthesize uniform Si-doped mesoporous WO (Si-mWO) microspheres with tunable sizes. The polymerization of the melamine-formaldehyde resin prepolymer (MF prepolymer) in the presence of silicotungstic acid hydrate (abbreviated as HSiW) leads to uniform MF/HSiW hybrid microspheres, which can be converted into Si-mWO microspheres through a simple thermal decomposition treatment process. In addition, benefiting from the pore confinement effect, monodispersed Pd-decorated Si-mWO microspheres (Pd/Si-mWO) were subsequently synthesized and applied as sensitive materials for the sensing and detection of hydrogen. Owing to the oxygen spillover effect of Pd nanoparticles, Pd/Si-mWO enables adsorption of more oxygen anions than pure mWO. These Pd nanoparticles dispersed on the surface of Si-mWO accelerated the dissociation of hydrogen and promoted charge transfer between Pd nanoparticles and WO crystal particles, which enhanced the sensing sensitivity toward H. As a result, the gas sensor based on Pd/Si-mWO microspheres exhibited excellent selectivity and sensitivity (/ = 33.5) to 50 ppm H at a relatively low operating temperature (210 °C), which was 30 times higher than that of the pure Si-mWO sensor. To develop intelligent sensors, a portable sensor module based on Pd/Si-mWO in combination with wireless Bluetooth connection was designed, which achieved real-time monitoring of H concentration, opening up the possibility for use as intelligent H sensors.
氢作为一种具有高能量密度的重要清洁能源，在燃料电池汽车和工业生产中受到了广泛关注。然而，考虑到其易燃易爆特性，在实际应用中迫切需要气体传感器来高效监测氢气浓度。在此，提出了一种简便的聚合诱导聚集策略，以合成尺寸可调的均匀硅掺杂介孔WO（Si-mWO）微球。三聚氰胺-甲醛树脂预聚物（MF预聚物）在水合硅钨酸（简称为HSiW）存在下聚合，形成均匀的MF/HSiW杂化微球，通过简单的热分解处理过程可将其转化为Si-mWO微球。此外，受益于孔限域效应，随后合成了单分散的钯修饰Si-mWO微球（Pd/Si-mWO），并将其用作氢气传感检测的敏感材料。由于钯纳米颗粒的氧溢流效应，Pd/Si-mWO比纯mWO能够吸附更多的氧阴离子。这些分散在Si-mWO表面的钯纳米颗粒加速了氢气的解离，并促进了钯纳米颗粒与WO晶体颗粒之间的电荷转移，从而提高了对氢气的传感灵敏度。结果，基于Pd/Si-mWO微球的气体传感器在相对较低的工作温度（210°C）下对50 ppm氢气表现出优异的选择性和灵敏度（/ = 33.5），比纯Si-mWO传感器高30倍。为了开发智能传感器，设计了一种基于Pd/Si-mWO并结合无线蓝牙连接的便携式传感器模块，实现了对氢气浓度的实时监测，为用作智能氢气传感器开辟了可能性。
