Nanoporous network of nickel oxide for ammonia gas detection

• Highly nanoporous and uniform network of NiO has been synthesized via a facile CBD method.
• Nanoporous NiO shows best response towards NH3 gas.
• Ni50 sample shows fast response and recovery time (average value is about 38 and 288 s) towards NH3.
• The fast response/recovery can be attributed to nanoporous structure, and large specific surface area.

The nanoporous network of nickel oxide (NiO) thin films have been synthesized by a facile chemical bath deposition method (CBD) at various deposition times. The X-ray diffraction (XRD) patterns of annealed NiO films revealed low intense peaks, confirming nanocrystalline nature with cubic structure. The scanning electron microscopy (SEM) images exhibited well-defined and nanoporous interconnected network. The gas sensing properties of NiO thin films for ammonia gas were investigated. The measurements revealed that the sample deposited at 50 min (Ni50) exhibit better gas sensing performance, due to its high surface area and maximum pore-volume available for gas adsorption.

SEM image of NiO showing nanoporous network and dynamic sensing transients of NiO sampleFigure optionsDownload as PowerPoint slide