Inkjet Printing of Solar Nanocomposites

The development of solar energy is pivotal in the shift of our energy infrastructure toward renewable sources. Renewables have begun to offset some of the demand for fossil fuel power production, but the ever increasing demand for energy has prevented the renewables from supplanting fossil fuel sources and significantly reducing annual carbon dioxide emissions. If we want to meaningfully combat climate change, we need to find ways to reduce the cost and increase the availability of photovoltaic cells. Solar bulk heterojunction polymer interfaces can be assembled and closely controlled through inkjet printing. The synthesis of  water based nanoinks eliminates toxic organic solvents, decreases costs, and increases the speed of film production. We are exploring methods to control print outcomes by varying nanoparticle size, print patterns, material constituents and concentrations, and post processing techniques. Conductive polymers and photoactive CdSe nanoparticles were purified using sub-micron filters and dispersed into water to create solar inks. These solar inks were inkjet printed to create solar nanocomposite thin films using a commercial Epson inkjet printer. Film homogeneity and print quality were characterized with tapping mode atomic force microscopy (AFM) and scanning electron microscopy. Photocurrents were studied using photoconductive AFM. Depositing nanomaterial films with inkjet printing has shown promise as a method for bulk heterojunction fabrication and low cost thin film deposition of inorganic-organic solar nanocomposites.