Aqueous PCDTBT:PC₇₁BM Photovoltaic Inks Made by Nanoprecipitation

Abstract

The fabrication of organic solar cells from aqueous dispersions of photoactive nanoparticles has recently attracted the interest of the photovoltaic community, since these dispersions offer an eco-friendly solution for the fabrication of solar cells, avoiding the use of toxic solvents. In this work, aqueous dispersions of pure poly[n-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl-C -butyric acid methyl ester (PC BM) nanoparticles, as well as of composite PC BM:PCDTBT nanoparticles, are prepared using the nanoprecipitation postpolymerization method. These dispersions are subsequently used to form the active layer of organic photovoltaic cells. Thin films of PC BM and PCDTBT are obtained by spray deposition of the nanoparticles' dispersions, and are characterized using a combination of spectroscopic and microscopic techniques. Photovoltaics that incorporate these active layers are fabricated thereafter. The impact of the annealing temperature and of the composition of the active layer on the efficiency of the solar cells is studied.

Overcoming efficiency and stability limits in water-processing nanoparticular organic photovoltaics by minimizing microstructure defects

“…Thus, a stabilizer is necessary to control the aggregations and to preserve the required microstructural morphology. Without stabilizers, it has not been able to stabilize nanoparticles in sufficiently concentrated solutions, disqualifying them for the fabrication of NP OPVs 33 .…”

Environmentally friendly preparation of nanoparticles for organic photovoltaics

“…[18][19][20] OPVs with active layers processed from a water or alcohol based nanoparticle dispersion has been reported in recent years. [21][22][23][24] These nanoparticles are processed from donor-acceptor blends either through a miniemulsion process with the presence of surfactant [25][26][27][28] or a precipitation method [21][22][23]29 . Furthermore, conjugated polymer nanoparticles were also reported to be synthesized by direct Suzuki-Miyaura dispersion polymerization.…”

Can Polymer Solar Cells Open the Path to Sustainable and Efficient Photovoltaic Windows Fabrication?

“…Multilayer P3HT : ICBA active layers produced through sequential deposition of NP from EtOH further improves the PCE to 4.2 % using a lower annealing temperature of 150 °C . Using water as non‐solvent for reprecipitation produced low PCEs below 0.2 % after annealing at 160 °C suggesting that EtOH might be a more adequate option when it comes to the fabrication of efficient PSCs from eco‐friendly nanoparticle dispersions …”