SnO2 nanoribbons as NO2 sensors: insights from first-principles calculations
Amitesh Maiti1, Josè A. Rodriguez2, Matthew Law3, Paul Kung*, 1, Juan R. McKinney3, and Peidong Yang3
1Accelrys Inc.,
San Diego, CA 92121 USA
2Brookhaven National Laboratory
3University of California, Berkeley
This is an abstract
for a presentation given at the
11th
Foresight Conference on Molecular Nanotechnology
SnO2 nanoribbons with exposed (1 0 1) and (0 1 0) surfaces have recently been demonstrated as highly effective NO2 sensors even at room temperature. The sensing mechanism is examined here through first-principles Density Functional Theory (DFT) calculations. We show that the most stable adsorbed species involve an unexpected NO3 group doubly bonded to Sn-centers. Significant electron transfer to the adatoms explains orders of magnitude drop in electrical conductance. X-ray absorption spectroscopy indicates predominantly NO3 species on the surface, and computed binding energies are consistent with adsorbate stability up to 700 K. Nanoribbon responses to O2 and CO sensing are also investigated.
*Corresponding Address:
Paul Kung
Accelrys Inc.
9685 Scranton Road
San Diego, CA 92121 USA
Phone: 1-858-799-5520 Fax: 1-858-799-5100
Email: [email protected]
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