Abstract:
Solar energy is a promising alternative energy source that can be used to replace the
environmentally hazardous and expensive fossil fuel. Among the various solar energy
converting devices solar cells are very important because they can convert solar energy
directly to electricity or to storable chemical energy. One of the biggest challenges in this
aspect is to find a suitable low cost, stable and environmentally friendly semiconductor
material that can be used in solar cell applications. Cuprous oxide is considered as an
important material in this regard because it is low cost, non toxic, and abundance of the
starting material copper. Semiconducting cuprous oxide has a direct band gap of 2 eV
and is ideal for photocatalytic water splitting reaction leading to hydrogen fuel. It is also
useful as a window material in some thin film PV solar cells. Electrodeposition
technique for preparation of thin cuprous oxide films is very important because it is
simple, low cost and can be used to control the conductivity type (n-type or p-type). In
this study, fabrication of p-n junctions of cuprous oxide for the applications in solar
energy converting devices is reported. It was observed that under specific controlled
conditions simple electrodeposition technique can be used to fabricate p-n junctions of
cuprous oxide thin films. Spectral response measurement of the photoelectrode in a
photoelectrochemical cell revealed the existence of the p-n junction and this is the first
evidence, to our knowledge, of the possibility of fabricating a cuprous oxide
homojunction.
