**Components of Natural Photosynthetic Apparatus in Solar Cells**

Roman A. Voloshin, Margarita V. Rodionova, Sergey K. Zharmukhamedov, Harvey J.M. Hou, Jian-Ren Shen and Suleyman I. Allakhverdiev

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/62238

#### **Abstract**

[49] Kluson P., Luskova H., Cerveny L., Klisakova J., Cajthaml T., J. Mol. Catal. A-Chem.,

[52] Lang X.J., Ji H.W., Chen C.C., Ma W.H., Zhao J.C., Angew. Chem., Int. Ed. 50 (2011)

[53] Furukawa S., Ohno Y., Shishido T., Teramura K., Tanaka T., ACS Catal., 1 (2011) 1150.

[55] Theurich J., Bahmemann D.W., Vogel R., Ehamed F.E., Alhakimi G., Raja I., Res. Chem.

[58] Soana F., Sturini M., Cermenati L., Albini A., J. Chem. Soc., Perkin Trans., 2 (2000) 699. [59] Woo O.T., Chung W.K., Wong K.H., Alex T., Chow B.C., Wong P.K., J. Hazard Mater.,

[60] Ohno T., Tokieda K., Higashida S., Matsumura M., Appl. Catal. A, 244 (2003) 383.

[62] Ohno T., Tokieda K., Higashida S., Matsumura M., Appl. Catal. A, 244 (2003) 383. [63] Kohtani S., Tomohiro M., Tokumura K., Nakagaki R., Appl. Catal. B, 58 (2005) 265.

[65] Geerlings P., De Proft F., Langenaeker W., Chem. Rev., 103 (2003) 1793.

[68] Selvam S., Swaminathan M., Catal. Commun., 12 (2011) 389.

[66] Cermenati L., Dondi D., Fagnoni M., Albini A., Tetrahedron, 59 (2003) 6409. [67] Subba Rao K.V., Subrahmanyam M. Photochem. Photobiol. Sci., 1 (2002) 597.

[61] Higashida S., Harada A., Kawakatsu R., Fujiwara N., Matsumura M., Chem. Commun.,

[64] Bekbolet M., Çınar Z., Kılıç M., Senem Uyguner C., Minero C., Pelizzetti E., Chemo‐

[56] Das S., Muneer M., Gopidas K.R., J. Photochem. Photo. A: Chem., 77 (1994) 83.

[57] Karam F. F., Kadhim M.I., Alkaim A.F., Int. J. Chem. Sci., 13 (2015) 650.

[50] Shiraishi Y., Morishita M., Hirai T., Chem. Commun. (2005) 5977.

[54] Naya S., Kimura K., H. Tada. ACS Catal., 3 (2013) 10.

[51] Yasutaka K., Yasuhiro M., Hiromi Y., Rapid Commun. Photosci., 4 (2015) 19.

242 (2005) 62.

160 Applied Photosynthesis - New Progress

Intermed., 23 (1997) 247.

168 (2009) 1192.

(2006) 2804.

sphere, 75 (2009) 1008.

3934.

Oxygenic photosynthesis is a process of light energy conversion into the chemical energy using water and carbon dioxide. The efficiency of energy conversion in the primary processes of photosynthesis is close to 100%. Therefore, for many years, photosynthesis has attracted the attention of researchers as the most efficient and ecofriendly pathway of solar energy conversion for alternative energy systems. The recent advances in the design of optimal solar cells include the creation of converters, in which thylakoid membranes, photosystems and whole cells of cyanobacteria immobilized on nanostructured electrode are used. As the mechanism of solar energy conversion in photosynthesis is sustainable and environmentally safe, it has a great potential as an example of renewable energy device. Application of pigments such as Chl *f* and Chl *d* will extend the spectral diapason of light transforming systems allow to absorb the farred and near infra-red photons of the spectrum (in the range 700-750 nm). This article presents the recent achievements and challenges in the area of solar cells based on photosynthetic systems.

**Keywords:** Solar cell, Thylakoids, Photosystem I, Photosystem II, Sensibilizator

#### **1. Introduction**

The energy crisis and environmental problems are among the most important challenges for humanity to solve in the twenty-first century. Many of the actual investigations are focused on the development of renewable, sustainable and eco-friendly energy sources [1].

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Nowadays, the available sources of renewable energy, including solar, wind, rain energy, energy of waves and geothermal heat, could generate only approximately 16% of the energy used [2]. Global energy consumption is about 17 TW according to the information of the year 2014 [3]. The flux density of sunlight emission near the ground surface is about 100 PW, which exceeds 5000 times our current needs [4]. Even though the solar period and the presence of clouds are taken into account, the sun is the extremely attractive source of energy, given we know how to extract it. Thus, sunlight is the most accessible and reliable source among the other renewable energy sources.

Photosynthesis is one of the main pathways of solar energy conversion, performed by higher plants, microalgae and some bacteria. Over 2.5 billion years, plant photosynthesis has evolved to convert solar energy into the chemical energy using only water as electron donor and proton source. This photosynthesis realises oxygen and is called oxygenic. Water, carbon dioxide and light are necessary for oxygenic phototrophic organisms to produce carbohydrates. The lightdependent reaction of photosynthesis takes place in the thylakoid membrane of photosynthetic organisms. The thylakoid membrane involves two photosystems (PSI and PSII), cytochrome b6f complex and other protein complexes embedded in a lipid bilayer. PSI and PSII can capture sunlight and create an electron-hole pair [5, 6]. The latter process operates with a quantum yield closer to 100%. Water, one of the most abundant substances on Earth, is the donor of electron for PSII [2].

For several decades, photovoltaic semiconductor devices have also been developed to generate electric power by converting sunlight directly into the electricity. The coefficient of efficiency of the light energy conversion into the electric current produced by commercial silicon photovoltaic cells is typically less than 20% [7]. Unfortunately, exhaustible materials and components used in photovoltaic systems cannot be fully recycled. Considering that the efficiency of energy conversion in the primary processes of photosynthesis is close to 100%, it is reasonable to use this natural process for energy conversion applications.

Recently, after critical analysis of the photosynthetic and photovoltaic energy conversion mechanisms, experts in the area of artificial photosynthesis concluded that it is difficult to compare the conversion efficiency of the current photovoltaic cells with that of the living photosynthesizing cells, as they are completely different systems [7]. The efficiency of photovoltaic cells can be calculated by dividing the cell's output power by the total solar radiation spectrum. However, the storage and energy transfer are not considered by this approach. Photovoltaic batteries, in which energy is stored, have high production cost and the expenses required for the maintenance of such systems. Photosynthesis stores solar energy in the form of chemical energy, which can further be converted into electrical energy [2].
