Ideal Solar Cells Containing One and Two Intermediate Bands by Non-linear Integral Equations

Yıl 2013, Cilt: 3 Sayı: 2, 270 - 275, 01.06.2013

Evangelos Ladopoulos

Öz

A new theory is proposed and investigated by using intermediate bands within the energy gap of the semiconductor in order to increase the efficiency of solar cells. Thus, the photons with energy less than the band gap could contribute to the output device by using the intermediate band or bands, in order to jump to the conduction band. Such a problem is reduced to the solution of non-linear integral equations and for their solution an innovative and groundbreaking numerical method is proposed. In general, in solar cells low energy photons can not excite electrons to the conduction band and then to the external circuit. Beyond the above, intermediate bands get advantage of the lower energy photons by allowing the electrons to be promoted to levels in the usually forbidden energy gap. Consequently, through such a multi-step approach, then the efficiency of the solar cell is increasing. In the current investigation will be shown that the maximum efficiency of an ideal solar cell containing one and two intermediate bands will be 63 % and 75 %, respectively.  

Anahtar Kelimeler

Solar Cell, Semiconductor, Intermediate Band, Conduction Band, Valence Band, Efficiency of Ideal Solar Cell, Non-linear Integral Equations, Photons, Electrons.

Kaynakça

• Luque A. and Marti A., 'Increasing the efficiency of ideal solar cells by photon induced transitions at intermediate levels', Phys. Rev. Lett., Vol. 78, pp. 5014 -5017, 1997.
• Green M.A., 'Third Generation Photovoltaics: Ultrahigh Conversion Efficiency at Low Cost', Progr. Photovolt., Vol. 9, pp. 123-135, 2001.
• Green M.A., 'Limiting Photovoltaics Light Conversion Efficiency', Progr. Photovolt., Vol. 9, pp. 257-261, 2002.
• Green M.A., Third Generation Photovoltaics, New York: Springer, 2006.
• Corkish R.P., Brown A.S. and Green M.A., ‘Limiting efficiency for a multi-band solar cell containing three and four bands', Physica E, Vol. 14, pp. 121-125. Nelson J., The Physics of Solar Cells, London: Imperial College Press, 2003.
• Luque A., Cuadra L. and Marti A., 'Present status of intermediate band solar cell research', Thin Solid Films., Vol. 451-452, pp. 593-599, 2004.
• McDougall J.and Stoner E.C., 'The computation of fermi- dirac functions', Phil. Trans. Roy. Soc. Lond., Vol. A , pp. 67-104, 1938.
• Blakemore J.S., ‘Approximations for femi-dirac integrals, especially the function used to describe electron density in a semiconductor’, Solid-State Electr., Vol. 25, pp. 1076.
• Tooper R.F., Ng E.W. and Devine C.J., ‘Chebyshev polynomial expansion of bose-einstein functions of orders 1 to 10’, Math. Comp., Vol. 23, pp. 639-643, Ladopoulos E.G., ‘Non-linear integro-differential equations used in orthotropic spherical shell analysis’, Mech. Res. Commun., Vol. 18, pp. 111-119, 1991.
• Ladopoulos E.G., ‘Non-linear integro-differential equations in sandwich plates stress analysis’, Mech. Res. Commun., Vol. 21, pp. 95-102, 1994.
• Ladopoulos E.G., ‘Non-linear singular integral representation for unsteady inviscid flowfields of 2-D airfoils’, Mech. Res. Commun., Vol. 22, pp. 25-34, 1995.
• Ladopoulos E.G., ‘Non-linear singular integral computational analysis for unsteady flow problems’, Renew. Energy, Vol. 6, pp. 901-906, 1995.
• Ladopoulos E.G., ‘Non-linear singular integral representation analysis for inviscid flowfields of unsteady airfoils’, Int. J. Non-Lin. Mech.,Vol. 32,.pp. 377-384, Ladopoulos E.G., ‘Non-linear multidimensional singular integral equations in 2-dimensional fluid mechanics analysis’, Int. J. Non-Lin. Mech., Vol. 35, pp. 708, 2000.
• Ladopoulos E.G., Singular Integral Equations, Linear and Non-Linear Theory and its Applications in Science and Engineering, Berlin, New York: Springer, Ladopoulos E.G., ‘Non-linear two-dimensional aerodynamics by multidimensional singular integral computational analysis’, Forsch. Ingen., Vol. 68, pp. 105- , 2003.
• Ladopoulos E.G., ‘Non-linear singular integral equations transformations’, Nonlin. Anal., Real World Appl., Vol. , pp. 531-536, 2005. by using Hilbert
• Ladopoulos E.G., ‘Unsteady inviscid flowfields of D airfoils by non-linear singular integral computational analysis’, Int. J. Nonlin. Mech., Vol. 46, pp. 1022-1026,
• Ladopoulos E.G., 'Non-linear singular integral representation for petroleum reservoir engineering', Acta Mech., Vol. 220, pp. 247-253, 2011.
• Ladopoulos E.G., 'Petroleum reservoir engineering by non-linear singular integral equations', J. Mech. Engng Res., Vol. 1, pp. 2-11, 2011.
• Ladopoulos E.G., 'Oil reserves exploration by non- linear real-time expert seismology', Oil Asia J., Vol. 32, pp. 30-35, 2012.
• Ladopoulos E.G., 'Hydrocarbon reserves exploration by real-time expert seismology and non-linear singular integral equations', Int. J. Oil Gas Coal Tech., Vol. 5, pp. 315, 2012.
• Ladopoulos E.G., 'Petroleum and gas reserves exploration by real-time expert seismology and non- linear seismic wave motion', Adv. Petrol. Expl. Develop., Vol.4,pp.1-18,2012.