One- and two-dimensional metal oxide nanostructures for chemical sensing

One- and two-dimensional metal oxide nanostructures for chemical sensing 

Key words metal oxide, chemical sensing, nanowires, films. 

Over the years, the demand for cheap, small, low power consuming but reliable solid-state chemical sensors has continued to grow. Consequently, significant research efforts have been made worldwide to improve on the 3Ss (sensitivity, selectivity and stability), mainly with empirical approaches, but also some basic theoretical research and spectroscopy studies. 

The metal oxide that has been paid the greatest attention for chemical sensing is Sn02 however, other oxides - such as I1O2, In203, WO3, ZnO, Fe203 - have been proposed and studied. Furthermore, the use of mixed oxides, as well as the addition of noble metals, has been studied to improve not only selectivity, but also stability. One of the most important articles in 

Another important discovery that changed the field of chemical sensing was the synthesis of single crystal one-dimensional oxide nanowires. These are created by the simple evaporation of the desired commercial metal oxide powders at high temperatures and their condensation at lower temperatures on the substrates. These materials have great potential thanks to their reduced lateral dimensions and single crystal habits, both for fundamental study and for potential nanodevice applications, i.e. the third generation of metal oxide gas sensors. 

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