Proceedings of International Conference Asia-Pacific Hybrid and Organic Photovoltaics (AP-HOPV17)
Publication date: 7th November 2016
Most of the Dye-sensitized Solar Cell (DSC) research has focused on the introduction of new dyes disregarding the redox mediator or the hole transport material. Nevertheless, the next breakthrough in improved efficiency of DSCs will come from adjusting the driving force for regeneration of the oxidized dye and moving towards a solid state system.1,2
Recently copper bipyridyl complexes Cu(dmby)2 (0.97 V vs SHE), Cu(tmby)2 (0.87 V vs SHE) and Cu(dmp)2 (0.94 V vs SHE) showed impressive solar-to-electrical power conversion efficiencies of 10.3% 10.0% and 10.3%, respectively, using liquid electrolyte and the organic Y123 dye under 1000 W m-2 AM1.5G illumination. In particular, the high photovoltages of over 1.0 V were achieved by the whole series of copper complex based redox mediators without compromising photocurrent densities and despite small driving forces of 0.1 V to 0.2 V for dye regeneration.3
The use of copper complexes also leads to a breakthrough in the indoor light-harvesting. We developed a DSCs with liquid electrolyte or solid HTM, which advances over other photovoltaic technologies, including GaAs thin film solar cells, in terms of efficiency and cost under the ambient and diffuse light conditions. As a practical result, we show that the performance of copper complex based DSCs in an indoor environment results is 16 μW/cm2 (at 200 lux) and 89 μW/cm2 (at 1000 lux), it is ∼15% larger power output than of a GaAs thin film solar cell, which sofar had the best performance under low light conditions. These characteristics will enable various indoor and diffuse light applications of DSC as useful power sources in the energy harvesting field.
1. Freitag, M.; Daniel, Q.; Pazoki, M.; Sveinbjornsson, K.; Zhang, J.; Sun, L.; Hagfeldt, A.; Boschloo, G. Energy Environ. Sci., 2015,8, 2634-2637.
2. Freitag, M.; Giordano, F.; Yang, W.; Pazoki, M.; Hao, Y.; Zietz, B.; Grätzel, M.; Hagfeldt, A.; Boschloo, G. J. Phys. Chem. C 2016, 120 (18), 9595.
3. Saygili, Y.; Söderberg, M.; Pellet, N.; Giordano, F.; Cao, Y.; Munoz-Garcia, A. B.; Zakeeruddin, S. M.; Vlachopoulos, N.; Pavone, M.; Boschloo, G.; Kavan, L.; Moser, J.-E.; Grätzel, M.; Hagfeldt, A.; Freitag, M. J. Am. Chem. Soc. 2016.