Fabrication and characterization of nanoporous ZnO layers for sensing applications

Top-Down Fabrication of Arrays of Vertical GaN Nanorods with Freestanding Top Contacts for Environmental Exposure

“…Further tests indicated that low power values (in the range of several hundred μW) are sufficient to heat up an array of 90 NRs to 200 °C, which means that around a few μW is required for a single NR. In terms of efficiency, this has led to specific Efficient Self-Heating (ESH) values [1] in the order of 10-100 K/μW, which is comparable with the best results achieved so far in literature but with a much easier fabrication process (instead of e.g., FIB-lithography and nanomanipulation) [1][2][3][4][5][6].…”

“…It has been demonstrated that 1D-nanorods, offer very large surface-to-volume ratio, high chemical-and thermal-stability, and dimensions comparable to the extension of surface charge region, which make them potential candidates for the development and production of simple, power-efficient, reliable, cost-effective, and sensitive gas sensors [1]. GaN nanorods in combination with surface coatings can lead to the sensor resistance changes under exposure to gases, even at very low concentration [2]. Previous works in the production of NRs for sensing purposes were mostly focused on other more conventional materials, like metal-oxides or carbon-nanostructures, and mostly with lateral orientation [3][4][5][6].…”

Fabrication of ZnO Nanorods on MEMS Piezoresistive Silicon Microcantilevers for Environmental Monitoring

“…ZnO nanomaterials, especially the ZnO 1D nanostructures such as nanowires, nanorods, nanopowders, and nanotubes have been recently attracting interest for the detection of humidity, chemicals and gases due to their large surface-to-volume ratio, high density of surface vacancies and chemisorption active sites [1,2]. Their low-cost facile fabrication process, good stability (due to the high crystallinity) and integration capabilities make it possible to fabricate ZnO nanostructure [3] on micro-cantilevers.…”

Nanostructured ZnO Materials: Synthesis, Properties and Applications

“…ZnO is a semiconductor with a bandgap of 3.37 eV [134], thus able to generate electron-hole couples when exposed to UV light. Moreover, the oxygen adsorbed on the surface in dark conditions under UV radiation is photodesorbed by capturing a photogenerated hole.…”