Advanced Flexible Tandem Organic Solar Cell Solution and Vacuum Technology

forthcoming

I intend to travel to the University of Oxford and the lab of Prof. Moritz Riede and build a second-generation version of indium tin oxide (ITO)-free flexible transparent electrodes (FTEs), which I have designed and built during my PhD studies at the University of Hong Kong in Hong Kong SAR. This will be designed not only to note excellent flexibility but also emphasize (1) excellent electrical and optical properties (i.e. sheet resistance <15 Ω sq.-1 and diffuse transmittance >90 %), (2) extremely smooth surface roughness (i.e. PtV <5 nm), (3) enlarged surface conducting channels, and (4) on-demand surface work function covering p- and n-type semiconducting properties, leading to a higher figure of merit (FoM) compared with industry-standard ITO on a glass substrate. In addition, an intermediate recombination layer (IRL) concept that electrically connects two sub-cells in a tandem cell will be devised by using arbitrary hole and electron transport layers (HTLs and ETLs) to advance consecutive manufacturing processes in a facility system without using the PEDOT:PSS. Once complete, I intend to break the record power conversion efficiency (PCE) of flexible tandem organic solar cells (FTOSCs) consecutively manufactured by solution (>20 %) and dry (>12 %) techniques respectively based on the developed on-demand p- and n-type ITO-free FTEs in this proposal, resulting in higher PCEs compared with the identical rigid tandem cells based on the rigid ITO. In addition, robust mechanical operation of the FTOSCs (>90 % PCE retention) under >36.5 k cycles (one year of use, if used 100 times a day) of repeated bending to a radius of 1.4 mm (e.g. Galaxy Z fold 2) based on the developed FTEs will be achieved under AM 1.5 G illumination standard for approximately 12 hours (time difference between sunrise and sunset). Finally, a large area for portable device scale (6-inch) for the ITO-free FTEs will be demonstrated by exploiting the unique spray coater in the host group.