With the decline in the world's natural resources, the need for new and cheaper energy sources is evolving. One such source is the sun which generates heat and light which can be harnessed and used to our advantage.

There are explanations of the principles behind this technology, the engineering required to produce these products and the future possibilities offered by this technology.

The chemistry and physics of the cells (both organic and inorganic) are clarified as well as production methods, with information how this can then be applied to the nanoscale as well.

 

A complete guide to this new and exciting way of producing energy which will be invaluable to a variety of people from material scientists, chemists, electrical engineers, to management consultants and politicians.

 

Mesoscopic solar cells

These new solar cells employ films composed of an interpenetrating network of

inorganic or organic semiconductor particles of mesoscopic (2–50 nm) size

forming junctions of very high contact area instead of the flat morphology used

by conventional thin-film cells. They are commonly referred to as ‘bulk’

junction cells due to their three-dimensional structure. The prototype of this

family of devices is the dye-sensitized solar cell (DSC), which accomplishes

optical absorption and charge separation by combining a light-absorbing

material (the sensitizer) with a wide band gap semiconductor of nanocrystalline

morphology (O’Regan & Graetzel 1991; Keshner & Arya, 2004). The DSC is

used in conjunction with electrolytes (Graetzel 2001), ionic liquids (Wang

2005a), polymer electrolytes (Haque et al. 2003) or organic (Bach et al. 1998) as

well as inorganic hole conductors (O’Regan 1997; Perera et al. 2003). Other

strategies employ blends of organic materials, such as polymeric (Halls et al.

1995) or molecular semiconductors (Peumans & Forrest 2001) as well as hybrid

cells using a p-type semiconducting polymer (such as poly 3-hexylthiophene),

in conjunction with a fullerene (Brabec et al. 2003) or CdSe ‘nanorods’

(Huynh et al. 2002).

These new dye-sensitized solar cells may be fabricated without expensive

and energy-intensive high temperature and high vacuum processes. They are

compatible with various supporting materials and can be produced in a variety

of presentations and appearances to enter markets for domestic devices and

architectural or decorative applications. The DSC conversion efficiency validated

at STC is currently 11.1% (Chiba et al. 2006). Excellent stability under

long-term illumination and high temperatures has been reached fostering

industrial applications.