Employment of inexhaustible solar energy is a promising choice to solve the energy shortage problems. In this respect, dye-sensitized solar cells (DSSCs) have attracted extensive interests because of their ease of fabrication and relatively high solar energy conversion efficiencies. Recently, Prof. Yongshu Xie and Prof. Wei-Hong Zhu cooperatively achieved remarkable results in the innovative design and cosensitization of DSSCs.
    As a class of traditional organic dyes, porphyrins have attracted intensive attention because of their strongly absorbing bands and prominent photoelectric behavior. But porphyrin dyes show extremely weak absorption in the near-infrared region and around 500 nm. To solve the problem, the near-infrared absorption was effectively enhanced and the aggregation was suppressed through optimizing the structures of porphyrin dyes (ZnP), improving the photocurrent and photovoltage; Finally, the cosensitization of the optimized porphyrin dye and WS-5 affords the highest efficiency of 11.5%, achieving a record for nonruthenium DSSCs based on iodine electrolyte. These results provide further insight into developing efficient DSSCs with synergistically enhanced photovoltage and photocurrent. This research work was recently published in Journal of the American Chemical Society (JACS, http://pubs.acs.org/doi/abs/10.1021/jacs.5b09665).

    On the other hand, the HOMO–LUMO energy gap of organic sensitizers should be large enough to enable efficient electron injection and dye regeneration. However, the LUMOs of most practical organic dyes are usually too high, making energy “waste”. In order to solve the problem, we focus on the targeted modulation of the molecular energy levels, ensuring the light response, energy levels and electron injection. These results provide innovative ideas for the development of D–A–π–A type of dyes. This research work was published in Chemical Science (http://pubs.rsc.org/en/content/articlelanding/2015/sc/c5sc02778k#divAbstract).

    The experiments were mainly completed by PhD students Yunyu Tang, Yueqiang Wang, Haibo Zhu, master candidate Jingchuan liu and a young teacher Wenjun Wu.
    In recent years, Prof. Wei-Hong Zhu group obtained a series of outstanding achievements in the design, function and stability of organic dyes, with a number of papers published in high-impact journals (Angew. Chem. Int. Ed., 2015, 54, 7275; JACS, 2015, 137, 8490; JACS, 2014, 136, 3579; Angew. Chem. Int. Ed., 2014, 53, 4603; Angew. Chem. Int. Ed., 2014, 53, 2090; Chem. Soc. Rev., 2015, 44, 417).
    Prof. Yongshu Xie group also achieved a series of important results in design, syntheses and properties of novel porphyrins and porphyrinoids (Angew. Chem. Int. Ed., 2014, 53, 10955; Angew. Chem. Int. Ed., 2014, 53, 14069; JACS, 2013, 135, 19119; Chem. Soc. Rev., 2015, 44, 1101).
    The aformentioned work was supported by the National Basic Research Program of China, Science Fund for Creative Research Groups, Distinguished Young Scholars, NSFC/China, and the Oriental Scholarship.