Work

Fabrication of metal organic framework/Polyoxometalate-TiO2 based DSCCs with enhanced electron lifetime and reduced recombination of charge carriers sensitized with cabbage/spinach cocktail natural dyes

Year: 2025

Type: article

Abstract: In an attempt to improve DSSCs efficiency, titanium dioxide (TiO 2 ) hybrid photoanode materials exuding electrocatalytic and photoelectrocatalytic were incorporated into iron based metal organic frameworks (MOFs) derived from BTC = 1,3,5-Benzenetricarboxylic acid and Bismuth based polyoxometalates (POMs). The combination of FeBTC and BiPOM were used to form enhanced photoelectrocatalytic properties, with different concentrations of N -doped carbon quantum dots (CQDs) as the light absorbing materials. The TiO 2 -FeBTC-BiPOM (6 %) nanocomposites doped with 400 μg/mL CQDs exhibited improved performance with lower charge transfer resistance. As a result, this electrode was used to fabricate a novel natural dye (chlorophyll, anthocyanin and cocktail mixture)-based DSSCs.The cocktail based mixture showed higher power conversion efficiency of 1.92 % compared to spinach based DSSCs (0.98 %) and purple cabbage (0.89 %) under 100 mW/cm 2 light illumination with 30 ms of electron lifetime, which is three times and four times more than spinach and cabbage based DSSCs respectively. In comparison to synthetic DSSCs, the efficiency of the natural dyes was still lower than N3 dyes. However, considering practical requirements of DSSCs, the natural dye-based devices satisfy most of the criteria such as affordability, ease of extraction, multiple wavelengths that can be absorbed with large coefficient, non-toxicity, and wide availability. Schematic of the fabrication of DSSCs using TiO 2 –Fe-BTC-BiPOM-C hybrid and natural dye cocktail. • Incorporation of BiPOM and FeBTC MOF onto TiO₂ enhances visible light absorption. • TiO₂-MOF/POM thin films exhibit high electron transfer kinetics due to carbon quantum dots as electron shuttles. • A combination of cabbage and spinach natural dyes improves efficiency. • Strong dye-TiO₂ interaction enhances DSSC thermal stability, ensuring durability.

Source: Chemistry of Inorganic Materials

DOI: 10.1016/j.cinorg.2025.100087

Authors: William Moloto, Pontsho Mbule, Edward Nxumalo, Bulelwa Ntsendwana

Institutions: University of South Africa, Mintek

Language: English

Topic: TiO2 Photocatalysis and Solar Cells

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: gold

Estimated APC paid: $1,280