Konarka Technologies Reveals Continuous Manufacturing Process for Flexible Nanomatrix Solar Cells

Konarka Technologies, Inc. (Lowell, MA) researchers have developed photovoltaic cells using carbon nanotubes that may be formed into a flexible fabric or textile. The photovoltaic material includes a fiber core having an outer surface, a light-transmissive electrical conductor, a photosensitized nanomatrix material, and a charge carrier material, where the photosensitized nanomatrix material and the charge carrier material are disposed between the outer surface of the fiber core and the light-transmissive electrical conductor.  The photosensitized nanomatrix material includes one or more types of interconnected metal oxide nanoparticles, and may also include a photosensitizing agent. The photosensitizing agent may be a dye or an organic molecule, such as a xanthine, cyanine, merocyanine, phthalocyanine, or pyrrole, according to U.S. Patent 7,622,667.   

Figure 11  shows an exemplary method for forming a flexible fiber including a photovoltaic material using a continuous manufacturing process.  

FIG. 11 shows a method 1100 for forming a photovoltaic
material in the form of a fiber using a continuous manufacturing process.
Referring to FIG. 11, a fiber 1101 is provided, for example, by a supply spool
1102. The fiber 1101 may be an electrically insulative fiber corecoated with an
electrical conductor, an electrically conductive fiber core, or a combination
of both. According to the illustrative embodiment, the fiber 1101 is coated
with a suspension of titanium dioxide nanoparticles and poly(n-butyl titanate)
(serving as a reactive polymeric linking agent) by passing it into such a fluid
suspension contained in a cup 1104 with a small hole in its bottom. Upon
exiting the cup 1104, the interconnected nanoparticle-coated fiber 1105 enters
an oven 1106 to remove excess suspending medium (e.g., water or other
solvent). 

 

If the solvent for the polyelectrolyte is a monomer,
it is preferably chosen such that it can be photopolymerized and such that the
resulting polymer structure does not detract from the electrical properties of
the polyelectrolyte. Hence, in the illustrative embodiment where the solvent
includes a monomer, the photoconversion material-coated fiber 1112 is passed
through a chamber containing UV lamps 1114, which initiate photopolymerization
of the monomer. The resultant fiber 1115 is then coated with the
photoconversion material including a solid state electrolyte, and may be
readily spooled onto a take-up spool 1116.
 

 

 

The photoconversion material-coated fiber 1115 then passes through or is placed in a vacuum chamber 1118 where a very thin layer of platinum, followed by a transparent, conductive coating of ITO, are deposited on the fiber. The platinum may be, for example, between about 15 .ANG. and about 50 .ANG. thick. The ITO serves as the significant light transmitting electrical conductor. The completed photovoltaic fiber 1119 may then be passed through a polymer solution 1120 to provide a transparent, protective coating, such as by wire extrusion or other means known to the art. Thus a flexible photovoltaic material 1121 is taken up on a finished spool 1122 and is ready for subsequent use in a weaving or matting operation.