Bidirectional Voltage Regulation for Integrated Photovoltachromic Device Based on P3HT-Electrochromic Unit and...

Area of Science:

• Materials Science
• Renewable Energy
• Electrochemistry

Background:

• Integrated electrochromic devices offer commercial potential but are limited by voltage mismatch.
• Efficient power conversion and electrochromic switching are key challenges.

Purpose of the Study:

• To develop a novel stand-alone integrated photovoltachromic device (I-PVCD) with improved voltage adaptability.
• To address the voltage adaption gap between photovoltaic cells and electrochromic materials.

Main Methods:

• Integration of perovskite/organic tandem solar cells (P/O-TSCs) with conjugated poly(3-hexylthiophene) (P3HT) electrochromic films.
• Introduction of C60 to lower the P3HT oxidation potential and PBDB-T as a hole transport layer in the interconnecting layer.
• Utilizing CsPbI2Br/PTB7-Th:IEICO-4F for P/O-TSCs to enhance open-circuit voltage (Voc).

Main Results:

• Achieved a reduced threshold voltage (Vt) of 0.70 V for the electrochromic layer.
• Enhanced the open-circuit voltage (Voc) of the P/O-TSC to 1.85 V.
• Demonstrated a coloration efficiency of 351.90 cm²/C and a switching time of 2 s.

Conclusions:

• The developed I-PVCD exhibits a wider self-adaptive voltage range, enabling efficient solar-powered color transitions.
• The device shows fast, reversible color changes from magenta to transparent under solar radiation.
• The I-PVCD demonstrates excellent operating reliability and promising commercial prospects.