Efficient and stable inverted perovskite solar cells with very high fill factors via incorporation of star-shaped polymer

Abstract

Stabilizing high-efficiency perovskite solar cells (PSCs) at operating conditions remains an unresolved issue hampering its large-scale commercial deployment. Here, we report a star-shaped polymer to improve charge transport and inhibit ion migration at the perovskite interface. The incorporation of multiple chemical anchor sites in the star-shaped polymer branches strongly controls the crystallization of perovskite film with lower trap density and higher carrier mobility and thus inhibits the nonradiative recombination and reduces the charge-transport loss. Consequently, the modified inverted PSCs show an optimal power conversion efficiency of 22.1% and a very high fill factor (FF) of 0.862, corresponding to 95.4% of the Shockley-Queisser limited FF (0.904) of PSCs with a 1.59-eV bandgap. The modified devices exhibit excellent long-term operational and thermal stability at the maximum power point for 1000 hours at 45°C under continuous one-sun illumination without any significant loss of efficiency.

A dopant-free hole transport material boosting the performance of inverted methylamine-free perovskite solar cells

“…S16,† which is defined as the trap filling limit voltage, V TFL ), at which the traps are completely filled. 45 The V TFL based on PTAA and PFDTS is determined to be 0.55 V and 0.43 V, which corresponds to a trap density of 3.63 × 10 16 cm −3 and 2.84 × 10 16 cm −3 , respectively. Therefore, the PFDTS based device has a lower trap density than the PTAA based one.…”

“…37 The enhancement of the FF is mainly attributed to the compact perovskite film formed on PFDTS, which has a lower trap density and lower charge recombination. 45 The enhanced hole extraction and retarded charge recombination are responsible for the improved J SC from PTAA to PFDTS. Moreover, there is a negligible hysteresis for the two devices, and the detailed photovoltaic parameter values are summarized in Table 1.…”

Critical Role of Removing Impurities in Nickel Oxide on High‐Efficiency and Long‐Term Stability of Inverted Perovskite Solar Cells

“…By comparison, several inorganic HTMs such as CuSCN, [7, 8] NiO x , [9–12] CuI, [13, 14] VO x and WO 3 have been used as substitutes for organic HTMs [15–17] . Among those, NiO x has attracted extensive attention because of its high optical transmittance, appropriate work function and inherent stability [18–22] . Currently, NiO x HTL can be produced by sputtering, electrodeposition, or pulsed laser deposition technologies [23–28] .…”

Designing Efficient MoS2/g‐C3N4 Hybrid Photocatalysts by Regulating the Interlayer Spacing of MoS2

“…Hydrogen energy is one of the most promising candidate for replacing traditional fossil fuels. [1][2][3][4][5][6][7][8][9][10][11] It is an effective method to produce hydrogen from water by photocatalytic technology and many efforts have been made to explore various kinds of potential semiconductors. Recently, g-C 3 N 4 as an appealing photocatalyst has received much attention due to its abundance, nontoxicity, and unique photoelectric properties.…”