Perovskite CIGS Tandem Solar Cells From Certified 24.2 toward 30 and Beyond

We demonstrate a monolithic perovskite CIGS tandem solar cell with a certified power conversion efficiency PCE of 24.2 . The tandem solar cell still exhibits photocurrent mismatch between the subcells; thus optical simulations are used to determine the optimal device stack. Results reveal a high optical potential with the optimized device reaching a short circuit current density of 19.9 mA cm 2 and 32 PCE based on semiempirical material properties. To evaluate its energy yield, we first determine the CIGS temperature coefficient, which is at amp; 8722;0.38 K 1 notably higher than the one from the perovskite subcell amp; 8722;0.22 K 1 , favoring perovskite in the field operation at elevated cell temperatures. Both single junction cells, however, are significantly outperformed by the combined tandem device. The enhancement in energy output is more than 50 in the case of CIGS single junction device. The results demonstrate the high potential of perovskite CIGS tandem solar cells, for which we describe optical guidelines toward 30 PC

Wettability Improvement of a Carbazole Based Hole Selective Monolayer for Reproducible Perovskite Solar Cells

The wettability issue associated with the Me 4PACz hole selective monolayer is solved by the introduction of the second component to the precursor solution. This results in a similar performance while simultaneously significantly improving the yield of the device

Conformal monolayer contacts with lossless interfaces for perovskite single junction and monolithic tandem solar cells

The rapid rise of perovskite solar cells PSCs is increasingly limited by the available charge selective contacts. This work introduces two new hole selective contacts for p i n PSCs that outperform all typical p contacts in versatility, scalability and PSC power conversion efficiency PCE . The molecules are based on carbazole bodies with phosphonic acid anchoring groups and can form self assembled monolayers SAMs on various oxides. Besides minimal material consumption and parasitic absorption, the self assembly process enables conformal coverage of arbitrarily formed oxide surfaces with simple process control. The SAMs are designed to create an energetically aligned interface to the perovskite absorber without non radiative losses. For three different perovskite compositions, one of which is prepared by co evaporation, we show dopant , additive and interlayer free PSCs with stabilized PCEs of up to 21.1 . Further, the conformal coverage allows to realize a monolithic CIGSe perovskite tandem solar cell with as deposited, rough CIGSe surface and certified efficiency of 23.26 on an active area of 1 cm2. The simplicity and diverse substrate compatibility of the SAMs might help to further progress perovskite photovoltaics towards a low cost, widely adopted solar technolog

Monolithic perovskite/silicon tandem solar cell with >29% efficiency by enhanced hole extraction

Tandem solar cells that pair silicon with a metal halide perovskite are a promising option for surpassing the single-cell efficiency limit. We report a monolithic perovskite/silicon tandem with a certified power conversion efficiency of 29.15%. The perovskite absorber, with a bandgap of 1.68 electron volts, remained phase-stable under illumination through a combination of fast hole extraction and minimized nonradiative recombination at the hole-selective interface. These features were made possible by a self-assembled, methyl-substituted carbazole monolayer as the hole-selective layer in the perovskite cell. The accelerated hole extraction was linked to a low ideality factor of 1.26 and single-junction fill factors of up to 84%, while enabling a tandem open-circuit voltage of as high as 1.92 volts. In air, without encapsulation, a tandem retained 95% of its initial efficiency after 300 hours of operation

Low Temperature Processed Fully Printed Efficient Planar Structure Carbon Electrode Perovskite Solar Cells and Modules

Scalable deposition processes at low temperature are urgently needed for the commercialization of perovskite solar cells (PSCs) as they can decrease the energy payback time of PSCs technology. In this work, a processing protocol is presented for highly efficient and stable planar n–i–p structure PSCs with carbon as the top electrode (carbon-PSCs) fully printed at fairly low temperature by using cheap materials under ambient conditions, thus meeting the requirements for scalable production on an industrial level. High-quality perovskite layers are achieved by using a combinatorial engineering concept, including solvent engineering, additive engineering, and processing engineering. The optimized carbon-PSCs with all layers including electron transport layer, perovskite, hole transport layer, and carbon electrode which are printed under ambient conditions show efficiencies exceeding 18% with enhanced stability, retaining 100% of their initial efficiency after 5000 h in a humid atmosphere. Finally, large-area perovskite modules are successfully obtained and outstanding performance is shown with an efficiency of 15.3% by optimizing the femtosecond laser parameters for the P2 line patterning. These results represent important progress toward fully printed planar carbon electrode perovskite devices as a promising approach for the scaling up and worldwide application of PSCs