A new development for solar paint shows a transformative one-step approach for designing nanocrystalline solar cells.
A transformative approach is required to meet the demand of economically viable solar cell technology. By making use of recent advances in semiconductor nanocrystal research, Prashant Kamat and his colleagues from the University of Notre Dame in the US, now developed a one-coat solar paint for designing quantum dot solar cells.
They prepared a binder-free paste consisting of CdS, CdSe, and TiO2 semiconductor nanoparticles and applied it to conducting glass surface and annealed at 473 K. Then they evaluated the photoconversion behavior of these semiconductor film electrodes in a photoelectrochemical cell consisting of graphene–Cu2S counter electrode and sulfide/polysulfide redox couple.
Open-circuit voltage as high as 600 mV and short circuit current of 3.1 mA/cm2 were obtained with CdS/TiO2–CdSe/TiO2 electrodes.
The students obtained also a power conversion efficiency exceeding 1% for solar cells constructed using the simple conventional paint brush approach under ambient conditions. Whereas further improvements are necessary to develop strategies for large area, all solid state devices, this initial effort to prepare solar paint offers the advantages of simple design and economically viable next generation solar cells. Read more in the latest ACS Nano, December 2011.