The advent of mesoscopic injection solar cells

Abstract

Mesoscopic injection solar cells operate in an entirely different fashion than conventional solar p‐n junction devices. Mimicking the principles that natural photosynthesis has used successfully over the last 3·5 billion years in solar energy conversion, they achieve the separation of light harvesting and charge carrier transport. The semiconductors used in conventional cells assume both functions simultaneously imposing stringent demands on purity and entailing high material and production costs. The prototype of this new PV family is the dye‐sensitized solar cell (DSC). The DSC has made phenomenal progress since its discovery was announced in the scientific literature only 14 years ago.1 Conversion efficiencies of 11·3% and excellent stability have been reached rendering it a credible alternative to conventional p‐n junction photovoltaic devices. The industrial development is advancing rapidly. Several enterprises currently produce modules and flexible cells on a pilot scale and commercial manufacturing of the DSC has recently been announced. It is asserted that this type of cell is a viable contender for large‐scale future solar energy conversion systems on the bases of cost, efficiency, stability and availability, as well as environmental compatibility. Copyright © 2006 John Wiley & Sons, Ltd.

Voltage enhancement in dye-sensitized solar cell using (001)-oriented anatase TiO2 nanosheets

“…The particles grown in HF-free medium had S BET 0150 m 2 /g and exhibited the usual bipyramidal crystal shape with (101) facets. This morphology resembles that of C240 particles optimized earlier for DSC applications [29].…”

“…The crystal morphology of C240 is characterized by particles ca. 10-20 nm in size exposing mainly the (101) facets, and it is frequently used for DSC [29]. The photoelectrochemical behavior of both reference materials was very similar.…”

High-Efficiency Dye-Sensitized Solar Cell with Three-Dimensional Photoanode

“…4À7 It is further hindered by the low electron mobility in anatase TiO 2 nanoparticles and the multiple grain boundaries in the mesoporous film. 8 Given a charge collection time of milliseconds at the maximum power point, 9 efficient charge extraction is only made possible when using the (I 3 À /I À ) redox couple through the slow interception of electrons by adjacent I 3 À . 10 In addition to limited light harvesting by the dye, one of the main limiting factors of efficiency is the excessive driving force of 0.6 eV necessary for the dye-regeneration process leading to a significant loss-in-voltage of approximately 600 mV.…”

“…A 22 vol % dispersion of 2.2 μm polystyrene macrospheres in isopropanol is doctor bladed on a TEC15 FTO-covered glass substrate to reveal a large-area highly light scattering disordered template. It is then heated and infiltrated with 90 nm of Al/ZnO (1:9), SnO 2 , or TiO 2 in a highly conformal fashion by atomic layer deposition (ALD) pulses of trimethylaluminum, diethylzinc and water (Al(Me) 3 , Zn(Et) 2 |H 2 O, 114°C, 1:9), tetrakis(dimethylamino)tin and ozone (Sn(NMe 2 ) 4 |O 3 , 200°C) and tetrakis(dimethylamino)-titanium and water (Ti(NMe 2 ) 4 |H 2 O, 200°C) using nitrogen as a carrier gas (Cambridge Nanotech Savannah S100). The infiltrated opal's top surface oxide is removed by RIE (6 min, 1800W, C 4 F 8 , Ar carrier gas, AMS200) performed before removing the polymer template by annealing (360°C, 15 min.)…”

Theoretical modelling of the electrode thickness effect on maximum power point of dye‐sensitized solar cell

“…Presently, DSSC can achieve as much as 10% energy conversion efficiency (Gratzel, 2001). The ongoing research and development focus on new DSSC materials for higher cell efficiency and theoretical modelling for insightful understanding of the basic working mechanisms (Ruile et al, 1997;Gratzel, 2000;Kron et al, 2002Kron et al, , 2003aKron et al, , 2003bRau et al, 2003;Durr et al, 2004;Fredin et al, 2005;Lenzmann et al, 2005;Gratzel, 2006;Ito et al, 2006;Kroon et al, 2006;Kumara et al, 2006;Ni et al, 2006a;Pettersson et al, 2006;Sastrawan et al, 2006). Some studies have been conducted to determine the effect of the TiO 2 electrode thickness on the DSSC performance.…”