tailieunhanh - Solar Cells New Aspects and Solutions Part 4

Tham khảo tài liệu 'solar cells new aspects and solutions part 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 96 Solar Cells - New Aspects and Solutions PV Technology Best cell PCEs Average cell PCEs Best module PCEs Average module PCEs Si bulk monocryst. Zhao et al. 1998 polycryst. Schultz et al. 2004 amorphous Benagli et al. 2009 --- monocryst. Zhao et al. 1997 polycryst. Schott 2010 monocryst. 13-15 polycryst. 5-7 amorphous CIGS thin film Jackson et al. 2011 --- MiaSolé 2010 10-14 CdTe thin film Wu X. et al. 2001 --- Cunningham et al. 2000 10 DSSC Han et al. 2006 5-9 5 38 Goldstein et al. 2009 --- OPV thin film Konarka 2010 Heliatek 2010 Mitsubishi 2011 3-5 Solarmer 2009 1-3 Table 1. Comparison of best and average PCE values of single solar cells and modules of different PV technologies. 2. Device structures and working principle Organic-inorganic hybrid solar cells are typically thin film devices consisting out of photoactive layer s between two electrodes of different work functions. High work function conductive and transparent indium tin oxide ITO on a flexible plastic or glass substrate is often used as anode. The photoactive light absorbing thin film consists out of a conjugated polymer as organic part and an inorganic part out of . semiconducting nanocrystals NCs . A top metal electrode . Al LiF Al Ca Al is vacuum deposited onto the photoactive layer finally. A schematic illustration of a typical device structure is shown in Fig. 1a. Generally there are two different structure types for photoactive layers - the bilayer structure Fig. 1b and the bulk heterojunction structure Fig. 1c . The latter one is usually realized by just blending the donor and acceptor materials and depositing the blend on a substrate. In contrast to bulk inorganic semiconductors photon absorption in organic semiconductor materials does not generate directly free charge carriers but strongly bound electron-hole pairs so-called excitons Gledhill et al. 2005 . Since the exciton diffusion lengths in conjugated .