Interface Electrode Morphology Effect on Carrier Concentration and Trap Defect Density in an Organic Photovoltaic Device

Kesavan, Arul Varman and Rao, Arun D and Ramamurthy, Praveen C (2017) Interface Electrode Morphology Effect on Carrier Concentration and Trap Defect Density in an Organic Photovoltaic Device. In: ACS APPLIED MATERIALS & INTERFACES, 9 (34). pp. 28774-28784.

PDF ACS_App_Mat_Int_9-34_28774_2017.pdf - Published Version Restricted to Registered users only Download (8MB) | Request a copy

Abstract

Formation of Schottky barrier contact (SBC) leads reconstruction of charges at the metal/semiconductor (MS) interface because of the wave function overlap between semiconductor and metal contact. Not only is the Schottky barrier contact formation a signature of the material's work function, but also it is sensitive to the interface trap states, the crystal orientation of the interacting materials, and other interface properties. In this work, the effect of aluminum cathode morphology on the polymer Schottky diode and bulk heterojunction (BHJ) photovoltaic device performance is studied. The electron collecting contacts in Schottky diode and BHJ device have been deposited using aluminum in pellet and nanoparticle forms. Devices fabricated by using Al nanoparticle showed improvement in dark as well as photocurrent density. Significant enhancement in Jsc leads to overall improved power conversion efficiency. Enhanced performance in Schottky structured diode and OPV device have been correlated with electrode microstructure and its interface properties such as improved electrically active contact and enhanced charge transport. Electrical conductivity is discussed based on enhanced electrical coherence across organic semiconductor and electrode interface. Therefore, the contribution of electrical enhancement leads to improvement in short-circuit current density (JO in BHJ solar cell which is due to reduced trap density. Further, PCE was correlated with the density of interface trap states studied by drive level capacitance profiling technique.

Item Type:	Journal Article
Publication:	ACS APPLIED MATERIALS & INTERFACES
Additional Information:	Copy right for this article belongs to the AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
Department/Centre:	Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy)
Date Deposited:	07 Oct 2017 06:06
Last Modified:	07 Oct 2017 06:06
URI:	http://eprints.iisc.ac.in/id/eprint/57991

Actions (login required)

View Item