Publications by authors named "I Kosta"

Reducing the interfacial recombination and improving the charge transfer capability of charge transport layers are effective strategies to enhance the efficiency and stability of perovskite solar cells (PSCs). This study evaluates, for the first time, the effects of selenophene substitution in the chemical structure of phenyl-butyric acid methyl ester (PCBM) on the performance and stability of inverted PSCs. Selenophene substitution was compared to thiophene and furan substitutions, and the reference PCBM without chalcogenophene moiety.

View Article and Find Full Text PDF

Despite the high efficiencies currently achieved with perovskite solar cells (PSCs), the need to develop stable devices, particularly in humid conditions, still remains. This study presents the synthesis of a novel photo-cross-linkable fullerene-based hole transport material named FT. For the first time, the photo-cross-linking process is applied to PSCs, resulting in the preparation of photo-cross-linked FT (PCL FT).

View Article and Find Full Text PDF

The incorporation of p-type functionalized carbon nanohorns (CNHs) in perovskite solar cells (PSCs) and their comparison with p-type functionalized single- and double-walled carbon nanotubes (SWCNTs and DWCNTs) are reported in this study for the first time. These p-type functionalized carbon nanomaterial (CNM) derivatives were successfully synthesized by [2 + 1] cycloaddition reaction with nitrenes formed from triphenylamine (TPA) and 9-phenyl carbazole (Cz)-based azides, yielding CNHs-TPA, CNHs-Cz, SWCNTs-Cz, SWCNTs-TPA, DWCNTs-TPA, and DWCNTs-Cz. These six novel CNMs were incorporated into the spiro-OMeTAD-based hole transport layer (HTL) to evaluate their impact on regular mesoporous PSCs.

View Article and Find Full Text PDF

The role of graphitic and amorphous nitrogen-doped carbon dots (N-CDs) as additives for perovskite solar cells (PSCs) is investigated. A detailed study of N-CDs: perovskite (PVSK) blends through X-ray diffraction, nuclear magnetic resonance, field emission scanning electron microscopy, UV-vis, and photoluminescence spectroscopy reveals the existence of interactions between N-CDs and PVSK. The amorphous or graphitic nature of these carbon nanoforms, as well as the interactions between CDs and PVSK, clearly determines the photovoltaic outcome of the PSCs.

View Article and Find Full Text PDF

A variety of novel chemically modified fullerenes, showing different electron-accepting capabilities, has been synthesized and used to prepare electron transport layer (ETL)-free solar cells based on perovskite/fullerene blends. In particular, isoxazolino[60] fullerenes are proven to be a good candidate for processing blend films with CH NH PbI and obtaining enhanced power conversion efficiency (PCE) ETL-free perovskite solar cells (PSCs), improving the state-of-the-art PCE (i.e.

View Article and Find Full Text PDF