Perovskite/Silicon Tandem Solar Cells: Choice of Bottom Devices and Recombination Layers

Abstract

Perovskite/silicon tandem solar cells have been intensively studied in recent years, and their efficiencies have rapidly increased owing to the numerous efforts in this field. A question about which type of silicon solar cell is the most suitable subcell in tandem devices emerges. Herein, three attractive silicon solar cells are summarized, including passivated-emitter rear-cell (PERC), tunnel oxide passivated contact (TOPCon), and heterojunction (HJT) cells. Their structures and features are elucidated for a clear understanding of the mechanism and potential of optimum performance. Moreover, the characteristics and performance of perovskite/silicon tandem cells with PERC, TOPCon, and HJT subcells are contrasted and discussed. The significant contribution of the passivation layer and structure design on both sides to photovoltaic properties of tandem devices is emphasized. Especially, the recombination layer between two subcells is analyzed in depth in terms of material chemistry, light absorption, and charge transport with a review on preparing the optimized structure.

Ionic Charge Imbalance in Perovskite Solar Cells

“…For an ion density of 5 × 10 17 cm −3 and interface recombination velocity, S v = 10 2 cm/s, case (i) provides T PCE of −0.15 rel %/°C, whereas that of case (ii) is −0.14 rel %/°C and −0.099 rel %/°C for case (iii). (Typical values of T PCE ranges from −0.17 rel %/°C to −0.08 rel %/°C in the literature; 57,59,60 however, T PCE values depend on the interface recombination 36 ). These results indicate that ionic imbalance could have a positive, even if small, influence on the temperature coefficients of perovskite solar cells.…”

Perovskite/Silicon Tandem Solar Cells: Insights and Outlooks

“…In PSTSCs, the PSCs with the wide bandgap will absorb the higher energy photons (wavelengths less than 800 nm) as the top cell (Figure 1b). 18 The Si cell with the narrow bandgap will absorb the lower energy photons (wavelengths less than 1100 nm) as the bottom cell, 18 realizing a segmented utilization of the solar spectrum (Figure 1c). 79 This avoids the thermalization losses of high-energy photons in single-junction devices (Figure 1d) 11 and increases the cell's solar energy utilization and PCE.…”

Challenges in the design and synthesis of self-assembling molecules as selective contacts in perovskite solar cells

“…In addition, their high performance in low light conditions and compatibility with other renewable energy sources have pushed the further industrialization of PSCs. 3–7…”

“…In addition, their high performance in low light conditions and compatibility with other renewable energy sources have pushed the further industrialization of PSCs. [3][4][5][6][7] Such as other photovoltaic devices, PSCs are made of a multilayer device structure in which the active and lightabsorbing layer (perovskite layer) is sandwiched between two charge transporting layers (CTLs), i.e., hole transporting layer (HTL) and electron transporting layer (ETL). [8][9][10] According to the direction of the current ow, perovskite devices can be divided into two well-known architectures: regular (n-i-p) and inverted (p-i-n) congurations (Fig.…”