Solar E→Z photoisomerization of azo switches

Abstract

By absorbing light energy, molecular photoswitches can undergo structural changes, store chemical energy, and perform dynamic work, which has profound impacts on the development of stimuli-responsive systems, energy storage/conversion materials, artificial molecular machines, etc. Developing photoswitches that can be fueled by natural sunlight will bring great benefits to their applications in the context of carbon neutrality. Here, we show that solar photoswitching can be realized by reshaping the absorption spectral profile, i.e., rendering the absorption of parent isomer overwhelmingly stronger than that of metastable isomer across the UV–Vis spectra. Solar E→Z photoisomerization of azo molecules—the most widely used class of photoswitches—are achieved by implementing this spectral tuning principle. A simple yet tunable molecular design strategy to meet this spectral requirement is established and a variety of solar photoisomerizable heteroaryl-based azo-switches are developed. Photoswitching under natural sunlight in place of the traditional artificial lights represents a crucial step towards sustainable light-driven processes.

A new immunological index for the elderly: high proportion of multiple TCR T cells based on scRNA-seq

“…Thymic involution leads to age-related aberrations in T cells which exacerbate the vulnerability to infections, impair the efficacy of vaccinations, and augment autoimmunity and tumor development. These consequences culminate in elevated morbidity and mortality among older adults [1,2]. The T-cell receptors (TCRs) generated during the development of T cells in the thymus play a vital role in the recognition of antigens and the activation of adaptive immune responses.…”