Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Phys Chem Chem Phys. 2012 Nov 14;14(42):14548-53. doi: 10.1039/c2cp43000b. Epub 2012 Sep 26.
We demonstrate series-integrated multijunction organic photovoltaics fabricated monolithically by vapor-deposition in a transposed subcell order with the near-infrared-absorbing subcell in front of the green-absorbing subcell. This transposed subcell order is enabled by the highly complementary absorption spectra of a near-infrared-absorbing visibly-transparent subcell and a visible-absorbing subcell and motivated by the non-spatially-uniform optical intensity in nanoscale photovoltaics. The subcell order and thicknesses are optimized via transfer-matrix formalism and short-circuit current simulations. An efficient charge recombination zone consisting of layers of BCP/Ag/MoOx leads to negligible voltage and series-resistance losses. Under 1-sun illumination the multijunction solar cells exhibit a power conversion efficiency of 5.5 ± 0.2% with an FF of 0.685 ± 0.002 and a V(OC) of 1.65 ± 0.02 V, corresponding to the sum of the V(OC) of the component subcells. These devices exhibit a broad spectral response (in the wavelength range of 350 nm to 850 nm) but are limited by subcell external quantum efficiencies between 20% and 30% over the photoactive spectrum.
我们展示了通过在反转型子电池顺序中蒸镀制造的串联集成型多结有机光伏器件，其中近红外吸收子电池在前，绿光吸收子电池在后。这种反转型子电池顺序是通过近红外吸收可见透明子电池和可见吸收子电池的高度互补吸收光谱实现的，并受到纳米级光伏中非空间均匀光强的驱动。通过转移矩阵公式和短路电流模拟对子电池顺序和厚度进行了优化。由 BCP/Ag/MoOx 层组成的高效电荷复合区导致了可以忽略不计的电压和串联电阻损耗。在 1 个太阳光照射下，多结太阳能电池的功率转换效率为 5.5 ± 0.2%，填充因子为 0.685 ± 0.002，开路电压为 1.65 ± 0.02 V，对应于组件子电池开路电压的总和。这些器件表现出宽光谱响应（波长范围为 350nm 至 850nm），但受到子电池外部量子效率的限制，在光活性光谱范围内为 20%至 30%。
