Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Porous Tin Oxide Nanostructured Microspheres for Sensor Applications



C Martinez, B Hockey, Christopher B. Montgomery, Stephen Semancik


There is a growing need to develop highly sensitive chemical sensors for applications such as military reconnaissance and toxic waste removal. A promising route for improving device performance is to use nanostructured materials (e.g. nanoparticles, nanowires, nanotubes) as sensor building blocks. We have sought to enhance the sensitivity of conductometric gas sensors through the design and fabrication of porous, three-dimensional tin oxide nanoparticle structures which have very high surface area. Films were fabricated via the self-assembly from solution of nanoparticle-decorated latex microspheres, which serve as sacrificial templates. Through heating, the latex microspheres were removed to reveal a 3-dimensional structure composed of interconnected spherical nanoparticle shells with porous ultra-thin walls. Sensor measurements were performed by depositing these films onto MEMS microsensor platforms with embedded inter-digitated electrodes and heaters. We report on film conductance changes measured at different temperatures, caused by exposure to test gases (CO, H2O, MeOH) in a dry air background. We also compare the performance of these high surface area films to films prepared through conventional routes such as CVD.
Proceedings Title
Sigma Xi Postdoctoral Poster Presentations, 2004
No. 17
Conference Dates
February 19-20, 2004


applications, microspheres, nanostructured


Martinez, C. , Hockey, B. , Montgomery, C. and Semancik, S. (2004), Porous Tin Oxide Nanostructured Microspheres for Sensor Applications, Sigma Xi Postdoctoral Poster Presentations, 2004 (Accessed April 18, 2024)
Created February 1, 2004, Updated February 17, 2017