Charge-tranfer mechanisms at interfaces between organic and inorganic materials in energy devices
Title: Charge-tranfer mechanisms at interfaces between organic and inorganic materials in energy devices
DNr: SNIC 2021/5-48
Project Type: SNIC Medium Compute
Principal Investigator: Lars Kloo <lakloo@kth.se>
Affiliation: Kungliga Tekniska högskolan
Duration: 2021-02-01 – 2022-02-01
Classification: 10499 10403 10407
Homepage: https://www.kth.se/sv/che
Keywords:

Abstract

This project will focus on the charge-transfer mechanisms at interfaces between organic and inorganic materials in emerging solar cell systems. In this sense, this is a contunation of the 2020/5-66 project, for which soon a final report will be submitted. This continued project will also involve investigations of the solid-electrolyte interfaces formed in Li-ion batteries, which conceptually are highly similar to the solar cell systems curently under study. Each type of system will be briefly described below: 1. Hole-transport materials in perovskite solar cells Perovskite and similar materials have opened a new field of reserach towards thin-film solar cells. However, the perovskite materials need to be sandwiched between other materials that extract photoinduced holes and electrons (exciton components) in order to generate high conversion efficiencies (from 3-4% to >20%). It is this type of interfaces that is of main interest. The group of Prof. Sun has published a series of new and exciting, polymeric, organic hole-transport materials (JACS 141, 2019, 19700; JACS 142, 2020, 17681). This sub-project will investigate the charge transfer between organic oligomers and the perovskite material at their interface. 2. Dye charge-transfer dynamics in dye-sensitized solar cells Dye-sensitized solar cells remain an attractive emerging solar cell technology owing to benign materials, reasonable conversion efficiencies and easy up-scaling possibilities. The essential step for improvement of performance and stability lies in the charge-transfer between the sensitizing organic or metal-organic dye molecules and the semiconducting substrate (typically) TiO2. It is clear that the dye organization is far more complexthan expected (Langmuir 28, 2012, 9431; PCCP 16, 2013, 711; ACS Appl. Mater. Interf. 9, 2017, 19773; ACS Appl. Energy Mater. 2, 2019, 124). The current study involves the effects of dye organization and electrolyte additives for a fundamental understanding at a molecular level. 3. Charge transfer at the Li-ion battery solid-electrolyte interface This project will initiated during the proposed project time. The main aim is to build a relevant solid-electrolyte interface and study charge-transfer and ion mobility at the interfaces. Special attention will be devoted to aqueous electrolytes, so-called Water-in-Salt lectrolytes (WiSE). The NSC has well-known efficient and powerful computation resources, which would facilitate our calculations.