Ameliorating Defects in Wide Bandgap Tin Perovskite Solar Cells Using Fluorinated Solvent and Hydrazide.

Surface passivation with multifunctional molecules is an effective strategy to mitigate the defect and improve the performance and stability of perovskite solar cells (PSCs). Here, the fabrication of a wide bandgap-PSC is reported with tin perovskite (WB-Sn-HP; bandgap: 1.68 eV), followed by molecular surface passivation using 4-Fluoro-benzohydrazide (F-BHZ).

Defect passivation in methylammonium/bromine free inverted perovskite solar cells using charge-modulated molecular bonding.

Molecular passivation is a prominent approach for improving the performance and operation stability of halide perovskite solar cells (HPSCs). Herein, we reveal discernible effects of diammonium molecules with either an aryl or alkyl core onto Methylammonium-free perovskites. Piperazine dihydriodide (PZDI), characterized by an alkyl core-electron cloud-rich-NH terminal, proves effective in mitigating surface and bulk defects and modifying surface chemistry or interfacial energy band, ultimately leading to improved carrier extraction.

Photoinduced ion-redistribution in CHNHPbI perovskite solar cells.

We use photoinduced absorption spectroscopy (PAS) to study the ionic motion in CHNHPbI perovskite solar cells, consisting of indium tin oxide (ITO)/NiOx/perovskite/phenyl-C-butyric-acid-methyl ester (PCBM)/aluminum-doped zinc oxide (AZO)/ITO. We observed a slow (∼50 mHz) spectral blue shift (∼10 eV) under modulated 520 nm illumination, which we interpreted in terms of the modulation in the bulk ion density. Numerical simulation shows that the mobile ion moves in and out from the double layers at the perovskite/charge transport layer interfaces in order to recover the bulk charge neutrality tipped off-balance by the photocarriers.

Unraveling the Impacts Induced by Organic and Inorganic Hole Transport Layers in Inverted Halide Perovskite Solar Cells.

The carrier transport layers (CTLs) have exhibited the influence on performance and stability of halide perovskite solar cells (HaPSCs). The exploration of characteristic impacts on HaPSCs induced by the CTL unveils the key factors underlying the device physics. In this work, we investigate the impacts of the organic or inorganic hole transport layer (HTL) in HaPSCs by analyzing the elemental distribution, the current-voltage characteristics, and the capacitance spectroscopy.

Tailoring the Open-Circuit Voltage Deficit of Wide-Band-Gap Perovskite Solar Cells Using Alkyl Chain-Substituted Fullerene Derivatives.

Wide-band-gap (WB) perovskite devices are promising as the top cell of silicon-perovskite tandem devices to boost the efficiency beyond the Shockley-Queisser limit. Here, we tailor the performance parameters of WB mixed-halide perovskite solar cell with long alkyl chain-substituted fullerene derivatives as an electron transport layer (ETL). The device with C-fused N-methylpyrrolidine- meta-dodecyl phenyl (CMC) demonstrates an enhanced power conversion efficiency of 16.