34%) than the Thick/NR cell (1 07%), while the EQE spectra are ve

34%) than the Thick/NR cell (1.07%), while the EQE spectra are very similar for both cells. On average, a 30% higher power conversion efficiency (η) was obtained for Thin/NR cells, as well as both higher fill factor (FF) and MEK162 mouse J sc than the Thick/NR architecture, as shown in the table in Figure 3, confirming the superior performance of the quasi-conformal design. The highest efficiency obtained for the Thin/NR cell (1.34%) is comparable to other results for conventional thick cells using nanorods of similar dimensions as ours, with reported efficiencies ranging from 1.02% to 1.59% [30–32]. It is

worth noting that in the case of the conformal cells, at least three times less volume of blend is used than in non-conformal cells (as estimated from SEM images). Taking this into account, the short-circuit current densities per unit volume of blend obtained are up to three times higher for the Thin/NR cells than for the Thick/NR ones. This requirement for a lower blend volume effectively means lower fabrication costs for hybrid cells implementing the Thin/NR architecture. Figure 3 EQE, J – V curves, PVD data and transient charge of best cells plus average photovoltaic

parameters. (a) EQE of best performing Thin/NR and Thick/NR cells (idealised cell selleck screening library designs in the inset). (b) J-V curves of best performing cells of both architectures produced in this selleck inhibitor study. Inset in (b) shows J sc as a function of light intensity for both types of cells. (c) Photovoltage decay lifetime of charges in both architectures as a function of light intensity. (d) Transient charge as a function of incident light intensity for both architectures. The table shows average photovoltaic parameters obtained from several devices for each of the two cell designs produced in this Arachidonate 15-lipoxygenase work. The rather low average values of V oc and FF observed are due to the fact that no seed layer was used prior to electrodeposition

of the ZnO NRA, which leaves some ITO exposed and in contact with the blend. This does not affect the evaluation of the conformal architecture since the reference thick/NR cells are made using the same type of NRAs; thus, the same effect takes place. Another related factor that may contribute to a lower average V oc in the conformal cell is that silver may pass through the extremely thin layer of organic blend, thus partially shorting the device. Assuming a similar or higher absorption in the Thick/NR architecture, the increase in efficiency for the Thin/NR cell indicates a more efficient charge extraction owing to the thin layer of blend [23]. The slightly higher EQE obtained for the Thick/NR cell can be explained by the fact that the EQE measurements were performed in the dark. Under low-intensity conditions charge carrier recombination only plays a minor role, which can lead to overestimated EQEs especially for devices with non-ideal charge percolation pathways.

Comments are closed.