Thermally Modulated Quartz Crystal Microbalance for Multimolecular Adsorption Decoupling: A Selective Desorption...

Area of Science:

• Materials Science
• Renewable Energy
• Surface Chemistry

Background:

• Dye loading in dye-sensitized solar cells (DSCs) is crucial for light absorption but excessive amounts cause aggregation, reducing performance.
• Coadsorbents like chenodeoxycholic acid (CDCA) prevent aggregation but can compete with dye molecules, leading to insufficient dye loading.
• Accurate quantification of individual molecular masses in mixed adsorption layers on TiO2 is challenging.

Purpose of the Study:

• To develop a method for direct quantification of N719 dye and CDCA coadsorbent surface masses on TiO2.
• To introduce a novel interface engineering strategy for optimizing dye loading and solar cell performance.
• To explore the potential of thermally selective desorption for surface modification.

Main Methods:

• Utilized temperature-modulated quartz crystal microbalance (QCM) technology to exploit thermal stability differences between N719 and CDCA.
• Developed a thermally selective quantitative detection approach for N719 and CDCA on TiO2.
• Implemented a novel adsorption site thermal maneuver supplementary sensitization (ASTM-SS) strategy.

Main Results:

• Demonstrated significant thermal stability differences between N719 dye and CDCA on TiO2 surfaces.
• Achieved direct quantification of N719 and CDCA adsorption using the developed thermal method.
• The ASTM-SS strategy enhanced N719 loading on TiO2 by 126.7%.
• Photovoltaic tests showed a 156.3% improvement in short-circuit current density (Jsc) and enhanced power conversion efficiency.

Conclusions:

• The study provides an innovative method for analyzing coadsorption systems and quantifying molecular masses on surfaces.
• Introduced a new paradigm for solar cell interface engineering via thermally selective desorption and supplementary sensitization.
• The developed strategy offers a universal approach for optimizing multimolecular adsorption systems, crucial for efficient and stable device development.