From Molecular Design to Application Potential: An All-Visible-Light Diarylethene Photoswitch with Near-Quantitative Photoconversion and High Photostability

Abstract

The development of visible-light photoswitches with high photoconversion efficiency remains a central challenge in advanced molecular photochemistry and is crucial for next-generation optical technologies. Here, we report a rationally engineered benzothiazole-based unsymmetrical dithienylethene (DTE) photoswitch that achieves bistable, near-quantitative interconversion between its open and closed states. The closed form exhibits an extraordinary thermal half-life exceeding 10,000 years, while the molecule shows no detectable photofatigue over 100 switching cycles. The molecular scaffold enables fully visible-light operation using violet and orange excitation, addressing a long-standing limitation of diarylethene systems. Comprehensive characterization─combining ultrafast spectroscopy, spectroscopic ellipsometry, and quantum-chemical simulations─reveals the mechanistic origins of its exceptional performance. Finally, we demonstrate the molecule’s potential in rewritable holography, anticounterfeiting, and all-optical switching, highlighting its promise as a robust platform for future light-driven information processing and authentication features.