Semiconductor-Olefin Adducts. Photoluminescent Properties of Cadmium Sulfide and Cadmium Selenide in the Presence of Butenes
Abstract
Direct evidence for adduct formation between butenes and etched, single-crystal n-CdS and n-CdSe(CdS(e)) surfaces has been obtained from photoluminescence (PL) measurements. Exposure of CdS(e) to butenes causes enhancement of the solids' band edge PL relative to a N2 ambient. For 30% mixtures of the olefins in N2, the magnitude of the enhancement follows the order, 1,3-butadiene > cis-2-butene trans-2-butene > isobutylene 1-butene, and correlates with the olefin basicities, based on photoionization potentials. Enhancements in PL intensity can be fit to a dead-layer model, allowing the determination of the reduction in depletion width in the semiconductor resulting from olefin exposure; depletion width reductions reach a few hundred Angstroms for adducts of 1,3-butadiene with CdS(e). The PL changes were used in conjunction with the Langmuir adsorption isotherm model to yield equilibrium constants for adduct formation of 1,3-butadiene with CdS(e) of 9 + or - 4 atm-1 at 293K. Surface interactions that may contribute to the observed PL changes are discussed. Cadmium selenide; Cadmium sulfide; Photoluminescence; Olefin detection; Cadmium compounds; Sulfides.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1988
- Accession Number
- ADA208348
Entities
People
- Arthur B. Ellis
- George C. Lisensky
- Gerald Meyer
- Jim C. Yu
- Larry K. Leung