Photonic enhancement of parallel homo-tandem solar cells through the central electrode

Abstract

We present here the effect of the common Ag electrode thickness, h 3 , in both TRTC and ITO-tandem configurations and also the I sc as a function of the active layer thickness in both TRTC and ITO-single configurations for the nine cell presented in Table I.

Photonic effect of a central ultrathin metal film on the performance of series and parallel homo-tandem solar cells

“…in our previous paper [20]. Figure 5 shows the role of the central UTMF and how we are able to manage the interferences.…”

“…We first study the theoretical material described by Eq. [20]. Hence, the optimal active layer thickness does not necessarly coincide with L max , see Figure 3.…”

“…Importantly, the extinction coefficient k(λ) decreases exponentially with a characteristic spectral width d beyond a cut-off wavelength, λ co . We have shown in [20] for 3T cells, that such a simplified refractive index can very accurately model realistic materials. For each of the four active material that we consider in this paper, we simulate the four cell types listed in Table 1, which we designate in the following by SC, 3T, 2T and 2T + .…”

“…In a previous paper [20], we have investigated parallel-connected, or threeterminal (3T) homo-tandem cells with emphasis on the optical role played by the central electrode. We have identified two mechanisms responsible of their outperformance compared to single cells (i) back-up absorption and (ii) microcavity effect intensified by the central metallic electrode.…”

“…We demonstrate this finding on a range of organic materials -PTB7-th:PC 71 BM, P3HT:PC 61 BM and DBP:C 70 -as well as with a theoretical material that displays a stepwise spectral absorption plus an Urbach tail. This last theoretical material was previously shown to faithfully reproduce the optical response of realistic ones [20]. To properly assess the advantage of placing an UTMF electrode in 2T + cells, we will also compare their performance against conventional 2T cells and single cells (SC).…”