The short-circuit current density in the GaAs/Si TSC achieves 37.8 mA/cm2 with experimentally possible parameters [41]. R. Lachaume et al. reported that over 30% efficiency could be achieved for the tandem with only ~7 μm of epi-SiGe and ZnO/Ag back metallization. In the latter ideal scenario, the highest efficiency achievable is ~37% with 1.1-μm-thick Al0.15Ga0.85 as top cell and epi-Si0.73Ge0.27 as bottom cell less than ~30-μm thickness [42]. Shizhao Fan et al. reported 1.7 eV/1.1 eV GaAs0.75P0.25/Si TSC having efficiency of 20.0% and 16.5% efficient GaAs0.75P0.25 single-junction top cell on Si and a 7.78% efficient GaAs0.75P0.25 filtered Si bottom cell (Figure 3.6) [43].
Figure 3.4 Fabricated 3-TGaAsP on SiGe/Si device. (Reprinted with the permission from reference [37].)
Figure 3.5 Schematic of GaAs nanowire-on-Si tandem solar cell. (Reprinted with the permission from reference [40].)
Manuel Schnabel et al. demonstrated tandem cell architecture with three terminals by combining GaInP and Si sub-cells to attain a GaInP/Si tandem cell with a two-terminal efficiency of 26.4 ± 1.0%. Three terminals show the efficiency of 0.9 ± 0.2% and two terminals show the efficiency of 27.3 ± 1.0% [44]. Nicolas Cavassilas et al. investigated, through a multiscale approach, a TSC based on a van der Waals heterostructure composed of two monolayers of transition metal dichalcogenides and predict that a PCE of 30.7% [45]. David M. Fabian et al. reported very efficient SJSC containing the dicationic material as a photoactive layer displayed an OCVP at 400 mV and SCPCD of ∼30 μA/cm2 (Figures 3.7 and 3.8) [46].
Colin D. Bailie et al. established semi-transparent cell onto CIGS and poor class multicrystalline Si to attain solid-state polycrystalline TSC efficiency above 25% [47]. Miguel Anaya and coauthors proposed a new tandem structural design in which both top and bottom cells are made of absorbers and devices shows the efficiencies at 35% [48]. Jiadong Qian et al. reported different degradation rates of perovskite cells and silicon cells in a tandem solar module degradation. PCE of 28.7% and 27.6% enable the economic viability of two- and four-terminal modules [49]. Alexander J. Bett et al. developed semi-transparent PSE in the regular n-i-p structure, which is presented with ITO directly sputtered on the hole conducting material Spiro-OMeTAD and showed efficiency of 14.8% [50].
Figure 3.6 (a) Schematic of the GaAsP/Si 2J cell. (b) Energy band diagram. (c) NRELmeasured EQE absorptance (1-R). (d) LIV 2J cell. The inset of panel (d): image of 0.138 cm2 2J cell. (Reprinted with the permission from reference [43].)
Figure 3.7 Crystal structure of (HDA)3CuBr8. (Reprinted with the permission from reference [46].)
Figure 3.8 (a) Absorption of thin films. (b) Normalized absorbance with respect of time. (Reprinted with the permission from reference [46].)
Abd. Rashid bin Mohd Yusoff et al. developed three photosensitive materials with a bandgap ranging from 1.3 to 1.82 eV. PCE obtained are of 10.39% and 11.83% on double-junction and triple-junction cell, respectively [51]. Mi-Hee Jung et al. reported flexible solar cell by combining nanopaper and perovskite in which bad gap is controlled by addition of Br ion into the CH3NH3PbI3. The MCE and IPCE were achieved with 6.37% and 40% at CH3NH3PbI3 perovskite, respectively [52]. Maximilian T. Hörantner et al. introduced a perovskite-on-silicon TSCs and determine that the ideal bandgap for a perovskite “top-cell” is 1.65eV, which has 32% efficiency. Furthermore, it shows that TSCs are yielding 30% energy output than single junction silicon (Figure 3.10) [53]. Marko Jost et al. presented monolithic perovskite/CIGSe TSC with a perovskite top cell. The performance is improved by the polymer PTAA at the NiOx/perovskite interface. This hole transport bilayer facilitates a 21.6% PCE at ∼0.8 cm2 area [54].
Figure 3.9 Schematic arrangement of the cell and its I-V characterstics. (Reprinted with the permission from reference in CC licenses [50].)
Figure 3.10 J-V characteristics (a) J-V of CIGSe single-junction. (b) Perovskite single junction reference cell with different HTLs. (Reprinted with the permission from reference [54].)
Yuqian Ai et al. fabricated sulfide-passivated ETL which improves the electron collection efficiency. Based on this S-SnO2 ETL, the PCE of the PSC is significantly promoted from 18.67% to 20.03% [55]. Afsal Manekkathodi et al. reported four-terminal (4T) tandem which provides a PCE exceeding 20%, for a perovskite-CQD TSC. The highest-performing front semi-transparent perovskite solar cells exhibit a PCE of 18% [56]. Philipp Loper and coauthors presented a four-terminal tandem consisting of a CH3NH3PbI3 top and a c-Si heterojunction bottom which has efficiency at 13.4% [57]. Yuhei Ogomi et al. reported Sn/Pb halide–based PSC and it shows best performance using CH3NH3Sn0.5Pb0.5I3 perovskite and 4.18% efficiency with VOC 0.42V, FF 0.50, and SCC 20.04 mA/cm2 Figures 3.11 to 3.13 [58].
Jialong Duan et al. fabricated FAPbX3 perovskite nanocrystals, high-melting-point ligands to modify the perovskite/carbon interface in allinorganic CsPbBr3 PSC, which are efficient PV device, and elevated PCE up to 8.55% is achieved [59]. Shichong et al. reported ICO transparent electrode with high mobility of 51.6 cm2/Vs, a low resistivity of 5.74 × 10−4 Ωcm and transmittance of 83.5%. The SHJ two-terminal TSC gets 8.06% step up in PCE from 18.85% to 20.37% [60]. Jian Liu et al. reported a two-terminal perovskite (PVSK)–organic HTSC and PFN/doped MoO3/MoO3 structure as interconnection layer (ICL). The HTSC attains VOC of 1.58V and FF of 0.68 [61].
