Traditionally, solar cells are made using a substance known as indium tin oxide (ITO). However, indium has become expensive due to high demand. Furthermore, solar cells made with ITO are expensive to make and fail when bent. The LBL OF CNTS FOR SCS (Preparation of ITO free transparent conductive electrode via layer-by-layer deposition of carbon nanotubes and its application for solar cells) initiative developed an ITO-free conductive electrode made from CNTs that can be used in solar cells. The biggest advantage of this method is that layer-by-layer (LBL) deposition allows scientists to control the coating thickness with the utmost precision. Scientists investigated three different LBL deposition techniques: conventional, spin assisted and spray assisted. They characterised the resulting CNT electrodes in terms of sheet resistance, optical transmission and morphology, and found that the conventional LBL method was superior. Researchers found that they could increase CNT film conductivity by treating it with various acids and heat. They determined that it is feasible to use CNTs in organic photovoltaic devices – the solar cells were as efficient as traditional devices. This research advanced the field of nano-structured conducting electrodes and may help scientists to develop flexible optoelectronics in the future.
Solar cells, carbon nanotubes, indium tin oxide, conductive electrode, layer-by-layer deposition