Prospects of hybrid organic-inorganic photovoltaic solar cells (original) (raw)

2017, Conference Paper: 2nd Fotonika-LV Conference “Achievements and Future Prospects”, 23-25 Apr 2017, Riga, Latvia, Book of Abstracts, Ed. A. Ubelis, D. Berzina, Riga: Univ. Latvia

Today organic-inorganic hybrid (OIH) semiconductor materials are a creative alternative for applications in electronics and photonics, particularly, for photovoltaic (PV) solar cells [1]. The approach is based on the next innovative solutions: (1) use of low-cost bio- or synthetic organic compounds for creating OIH suitable for broad-band sunlight harvesting and PV energy conversion; (2) use of process of molecular self-organization and assembly for OIH growing at room temperature; (3) use of technology of thin film chemical deposition from a colloidal solution; and (4) use of smart technique of differential analysis of functional characteristics for optimization of OIH performance [2, 3]. According to our study of various samples of low-molecular-weight OIH cells fabricated on patterned Si substrates, including its structural, optical and electrical characterisation, such PV cells have the following features: (i) PV efficiency of energy conversation is up to 9% depending on the chemical composition and surface/ interface morphology; (ii) performance of the Si-based OIH of thiamine diphosphate hydrochloride (C12H20Cl2N4O7P2S cocarboxylase or Vitamin B1) for a thin layer of 30 nm and a self-organized net-like surface was found to be the best; (iii) intense optical absorption followed by photoluminescence in the range 400–900 nm, whose spectral distribution and peak have vibrionic origins; and (iv) there is a number of characteristic bands associated to functional groups containing amines NHx(x = 0, 1, 2), carboxamides CON, cyanides CN, hydrocarbons CHx(x = 1, 2, 3), hydroxyl OH, carbonyl CO, etc. Despite the limited understanding of the complex mechanism of charge-carrier transfer in such OIH, the classic model of electron-hole pair generation, charge separation, and recombination proved to be suitable to describe current-voltage characteristics, when the short circuit current Isc is a linear function of energy of irradiation, and the open circuit voltage Voc has a logarithmic dependence of energy followed by saturation. We found that even small changes in the OIH design can lead to essential differences in optical and electrical properties, however a proper technological manipulation can help to optimize the OIH performance to the desired results. Research is in progress. The authors acknowledge support of the EU FP7-PEOPLE-IRSES-2011-204949 NOCTURNAL ATMOSPHERE, FP7-PEOPLE-IRSES-2012-318820 BIOSENSORS-AGRICULT, and National RTD Program NASU “SENSOR TECHNOLOGIES” 2008-2015, Project 1.4.10. References [1] G. Li, R. Zhu, Y. Yang, Polymer solar cells, Nature Photonics 6, 15-161 (2012) [2] T.Ya. Gorbach, P.S. Smertenko, E.F. Venger, Investigation of photovoltaic and optical properties of self-organized organic-inorganic hybrids using aromatic drugs and patterned silicon, Ukr J Phys, 59(6): 601-611 (2014) [3] V. Naumov, P. Smertenko, G. Olkhovik, S. Stepanov, Differential approach and radiation amplification factor, in 73rd Annual Sci. Conf. Univ.Latvia, 6-7 Feb 2015, Riga, Latvia, Book of Abstracts, Ed. A.Atvars, V.Beldavs, A.Ubelis, Riga Photonics Centre Univ.Latvia, p.62 (2015)