Liang Yuan-Chang, Chang Yen-Cheng, Zhao Wei-Cheng
Department of Optoelectronics and Materials Technology, National Taiwan Ocean University, Keelung 20224, Taiwan.
Nanomaterials (Basel). 2020 Oct 9;10(10):1989. doi: 10.3390/nano10101989.
The porous zinc oxide-nickel oxide (ZnO-NiO) composite nanosheets were synthesized via sputtering deposition of NiO thin film on the porous ZnO nanosheet templates. Various NiO film coverage sizes on porous ZnO nanosheet templates were achieved by changing NiO sputtering duration in this study. The microstructures of the porous ZnO-NiO composite nanosheets were investigated herein. The rugged surface feature of the porous ZnO-NiO composite nanosheets were formed and thicker NiO coverage layer narrowed the pore size on the ZnO nanosheet template. The gas sensors based on the porous ZnO-NiO composite nanosheets displayed higher sensing responses to ethanol vapor in comparison with the pristine ZnO template at the given target gas concentrations. Furthermore, the porous ZnO-NiO composite nanosheets with the suitable NiO coverage content demonstrated superior gas-sensing performance towards 50-750 ppm ethanol vapor. The observed ethanol vapor-sensing performance might be attributed to suitable ZnO/NiO heterojunction numbers and unique porous nanosheet structure with a high specific surface area, providing abundant active sites on the surface and numerous gas diffusion channels for the ethanol vapor molecules. This study demonstrated that coating of NiO on the porous ZnO nanosheet template with a suitable coverage size via sputtering deposition is a promising route to fabricate porous ZnO-NiO composite nanosheets with a high ethanol vapor sensing ability.
通过在多孔氧化锌（ZnO）纳米片模板上溅射沉积氧化镍（NiO）薄膜，合成了多孔氧化锌-氧化镍（ZnO-NiO）复合纳米片。在本研究中，通过改变NiO溅射持续时间，在多孔ZnO纳米片模板上实现了不同的NiO薄膜覆盖尺寸。本文对多孔ZnO-NiO复合纳米片的微观结构进行了研究。多孔ZnO-NiO复合纳米片形成了粗糙的表面特征，较厚的NiO覆盖层缩小了ZnO纳米片模板上的孔径。在给定的目标气体浓度下，基于多孔ZnO-NiO复合纳米片的气体传感器对乙醇蒸汽表现出比原始ZnO模板更高的传感响应。此外，具有合适NiO覆盖含量的多孔ZnO-NiO复合纳米片对50-750 ppm乙醇蒸汽表现出优异的气敏性能。观察到的乙醇蒸汽传感性能可能归因于合适的ZnO/NiO异质结数量以及具有高比表面积的独特多孔纳米片结构，该结构在表面提供了丰富的活性位点以及乙醇蒸汽分子的众多气体扩散通道。这项研究表明，通过溅射沉积在多孔ZnO纳米片模板上以合适的覆盖尺寸涂覆NiO是制备具有高乙醇蒸汽传感能力的多孔ZnO-NiO复合纳米片的一条有前途的途径。
