Solid and gel layered polyelectrolytes for application in dye solar cells

Author(s)

Marcos Antonio Santana Andrade Junior

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Química
• Defense date: 2016-07-18

Examining board members

Heloise de Oliveira Pastore; Jilian Nei de Freitas; Claudio Jose de Araujo Mota; Lázaro Aurélio Padilha Junior; Francisco das Chagas Marques

• Advisor: Heloise de Oliveira Pastore

Abstract

Dye solar cells were assembled with quasi-solid electrolytes prepared by gelling a reference liquid electrolyte. Polyamidoamine (PAMAM) and polydiamidodiaminepyridine (PAMPy) dendron-functionalized organotalcs and their respectives dendron-iodine charge-transfer complexes modified materials were used as gelling agents. The characteristics of the solar cells obtained from the potential-current curves were increased values of energy conversion efficiency to the cells comprised by PAMAM-talc-G5-I2 and PAMPy-talc-G1-I2 electrolytes compared to the reference liquid solar cells, respectively, an increase of 5 and 12.5 %. The transport of charges into the solar cells was evaluated based on the results of electrochemical impedance spectroscopy in the dark and under illumination at 100 mW cm-2 and by incident photon-to-current spectroscopy (IPCE). Solar cells stability was investigated under constant illumination at 100 mW cm-2 using an automatic data record system SCATU (Solar Cells Aging Test) and by an image analysis method applying the RGB colors model to study the tri-iodide bleaching, which is the main cause of decreasing efficiency. PAMAM-talc-G5 removes iodine from electrolyte during gelling process leading to the degradation of thesolar cell during the aging. Intercalation of polyiodides into this material produces PAMAM-talc-G5-I2, and adding this organotalc to the DSSCs resulted in a very stable device, presenting a decreased charge-transfer resistance, mass-transport impedance in the counter electrode/electrolyte interface and also decreased charge-transfer-resistance in photoelectrode/electrolyte due to the increased triiodide concentration. Solar cells assembled by electrolytes gelled by PAMPy-talc organotalcs presented low tri-iodide removal from electrolyte without affecting their stability (AU)

• FAPESP's process: 13/05911-1 - Layered solid and gel polyelectrolytes for application in dye solar cells
• Grantee: Marcos Antonio Santana Andrade Junior
• Support Opportunities: Scholarships in Brazil - Doctorate