Memory effect of CdSe/ZnS nanoparticles embedded in a conducting poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] polymer layer

Capacitance-voltage (C-V) measurements on Au/a conducting poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] polymer layer containing core/shell CdSe/ZnS nanoparticles (hybrid layer)/indium tin oxide (ITO) coated glass and Al/hybrid layer/ITO coated glass capacitors at 300 K showed metal-insulator-semiconductor behavior with a large flatband voltage shift. This shift was due to the existence of the CdSe/ZnS nanoparticles, indicative of trapping, storing, and emission of charge carriers in the CdSe/ZnS nanoparticles. Symmetric and asymmetric C-V characteristics appeared in the Al/hybrid layer/ITO coated glass and Au/hybrid layer/ITO coated glass capacitors, respectively. A dipolar carrier trapping model is proposed to explain the symmetric behavior in the C-V curve. (C) 2007 American Institute of Physics.