Human-friendly semitransparent organic solar cells achieving high performance†
Abstract
Semitransparent photovoltaic (ST-PV) devices transmitting enough light and generating electricity have become one of the research frontiers in emerging PV systems including organic, perovskite, quantum dot and dye-sensitized solar cells in recent years. Such semitransparent devices can be integrated into house curtain walls, intelligent windows and plant greenhouse, simultaneously increasing the solar energy collection area and architectural aesthetics. Although the light utilization efficiencies (LUEs) of single-junction devices have exceeded 3.5%, research studies about ST-PV devices are still missing an important element: the human-to-device interaction, as the long-time exposure to solar irradiation or even such semitransparent modules would unfortunately cause photoinduced diseases such as erythema, skin aging, cataracts and even blindness. Herein, we systematically evaluated the photobiological safety of mainstream ST-PV devices and fabricated a series of high-performance human-friendly ST-PV devices with LUE values exceeding 5.0% and low skin/eye damage levels for human beings. Impressively, such solar cells combine ultraviolet and blue light filtering structures to achieve comprehensive protection against light hazards and record safety working extremum (SWE) values for all-around skin and eye protection. This work not only establishes an important principle to evaluate the human-to-device interaction of ST-PV devices for the first time, but also demonstrates an effective integrated optesthesia-dermato control method by using aperiodic band-pass filters (ABPF) without sacrificing device performance.