Recently, a paper of “A strategy to design novel structure photochromic sensitizers for dye-sensitized solar cells” (http://www.nature.com /srep/2015/150226/ srep08592/pdf /srep08592.pdf) was published in the journal of Scientific Reports (an online, open access journal from the publishers of Nature). This work was published by Associate Researcher Wenjun Wu group (School of Chemistry and Molecular Engineering, East China University of Science & Technology). Thanks to the photochromic effect the sensitizers have under ultraviolet and visible light, the conjugated bridge can be restructured and the resulting two photoisomers showed different behaviors in photovoltaic devices. This opens up a new research way for the DSSCs.

    In the past two decades considerable scientific and industrial attention has been focused on dye-sensitized solar cells (DSCs) because of the low cost, environmental friendliness, and simple preparation procedures for various photovoltaic devices. At present, there are two research interests on DSCs: First, the development of high efficiency dye sensitizers; the second is multi-functionalization of sensitizers. For example, the water splitting with DSCs cells have received great attention. As a new research topic, how to freely control its photoelectric conversion efficiency with same sensitizer? Researchers have tried to introduce the photochromic bisthienylethene (BTE) unit into π-bridge of D-π-A structure sensitizer. The photovoltaic signal can be switched between two isomers under UV or visible light irradiation. This result is an important progress in the research of PV control of the DSC with one sensitizer.
    Next , some other works, such as the stability of photochromic sensitizers, the photochromic control of dyes adsorbed on TiO2 film and the electronic recombination performance of the interface between photochromic sensitizers and TiO2 semiconductor, need to do continuously.
    This work was supported by the National Basic Research 973 Program and NSFC/China hosted by Prof. He Tian and the Science Fund for Creative Research Groups by Prof Yitao Long .