Enhancing Planar Inverted Perovskite Solar Cells with Innovative Dumbbell‐Shaped HTMs: A Study of Hexabenzocoronene and Pyrene‐BODIPY‐Triarylamine Derivatives

Abstract

Dumbbell‐shaped systems based on PAHs‐BODIPY‐triarylamine hybrids TM‐(01‐04) are designed as novel and highly efficient hole‐transporting materials for usage in planar inverted perovskite solar cells. BODIPY is employed as a bridge between the PAH units, and the effects of the conjugated π‐system's covalent attachment and size are investigated. Fluorescence quenching, 3D fluorescence heat maps, and theoretical studies support energy transfer within the moieties. The systems are extremely resistant to UVC 254 nm germicidal light sources and present remarkable thermal stability at degradation temperatures exceeding 350 °C. Integrating these systems into perovskite solar cells results in outstanding power conversion efficiency (PCE), with TM‐02‐based devices exhibiting a PCE of 20.26%. The devices base on TM‐01, TM‐03, and TM‐04 achieve PCE values of 16.98%, 17.58%, and 18.80%, respectively. The long‐term stability of these devices is measured for 600 h, with initial efficiency retention between 94% and 86%. The TM‐04‐based device presents noticeable stability of 94%, better than the reference polymer PTAA with 91%. These findings highlight the exciting potential of dumbbell‐shaped systems based on PAHs‐BODIPY‐triarylamine derivatives for next‐generation photovoltaics.

Unveiling the Role of BODIPY Dyes as Small‐Molecule Hole Transport Material in Inverted Planar Perovskite Solar Cells

“…This observation suggests the presence of an energy transfer mechanism from the donor units to the BODIPY core, impacting the fluorescence decay characteristics. [27,45] The electrochemical properties of the BODIPY derivatives were investigated using cyclic (CV) and square wave (SW) voltammetry, performed in anhydrous THF solutions with a three-electrode system, Fc/Fc þ serving as the internal reference. The findings, including the estimated HOMO and LUMO energy levels, are detailed in Table 2.…”

“…Such a density functional has proved to be reliable in the description of energy and electronic structure of similar systems. [27,53] As shown in Table 3 and Figure S13, Supporting Information, the absorption wavelengths of PyBDP-1 have been estimated in THF and toluene as implicit solvents in the framework of time-dependent DFT approximation. The highest wavelength calculated in each solvent (695 and 694 nm, respectively) exhibit no notorious deviations one to each other, but the intensities (oscillator strength values of 1.23 and 1.28, respectively).…”

“…[21][22][23][24] Additionally, the integration of arylamines into BODIPY derivatives not only amplifies these intrinsic properties but also exploits the strong electron-donating capacity of arylamines, thereby improving the charge transport properties essential for efficient HTMs. Although the BODIPY core has been employed in the design of small moleculebased HTMs, dopant-free polymeric HTMs, and tailor-made interlayers, resulting in high power conversion efficiency (PCEs), [25][26][27][28][29] research on BODIPY-based HTMs remains limited, with just a few studies documenting their use. [25][26][27] This study introduces five novel small molecule BODIPY dyes (PyBDP 1-5) with extended conjugation at the α-positions, by integrating arylamine donors such as triphenylamine, carbazole, and phenothiazine, designed to enhance the optoelectronic properties and stability required for effective HTMs.…”

“…Although the BODIPY core has been employed in the design of small moleculebased HTMs, dopant-free polymeric HTMs, and tailor-made interlayers, resulting in high power conversion efficiency (PCEs), [25][26][27][28][29] research on BODIPY-based HTMs remains limited, with just a few studies documenting their use. [25][26][27] This study introduces five novel small molecule BODIPY dyes (PyBDP 1-5) with extended conjugation at the α-positions, by integrating arylamine donors such as triphenylamine, carbazole, and phenothiazine, designed to enhance the optoelectronic properties and stability required for effective HTMs. It was conducted photophysical, electrochemical and thermal studies to explore their optoelectronic properties.…”