Ti3C2Tx-Modified PEDOT:PSS Hole-Transport Layer for Inverted Perovskite Solar Cells

Abstract

PEDOT:PSS is a commonly used hole-transport layer (HTL) in inverted perovskite solar cells (PSCs) due to its compatibility with low-temperature solution processing. However, it possesses lower conductivity than other conductive polymers and metal oxides, along with surface defects, limiting its photovoltaic performance. In this study, we introduced two-dimensional Ti3C2Tx (MXene) as an additive in the PEDOT:PSS HTL with varying doping concentrations (i.e., 0, 0.03, 0.05, and 0.1 wt.%) to tune the electrical conductivity of PEDOT:PSS and to modify the properties of the perovskite film atop it. We noted that the grain size of the CH3NH3PbI3 (MAPI3) perovskite layer grown over an optimal concentration of MXene (0.03 wt.%)-doped PEDOT:PSS increased from 250 nm to 400 nm, reducing charge recombination due to fewer grain boundaries. Ultraviolet photoelectron spectroscopy (UPS) revealed increased work function (WF) from 4.43 eV to 4.99 eV with 0.03 wt.% MXene doping, making the extraction of holes easier due to a more favorable energy level alignment with the perovskite. Quantum chemical investigations based on density functional theory (DFT) were conducted at the ωB97XD/6-311++G(d,p) level of theory to provide more insight into the stability, bonding nature, and optoelectronic properties of the PEDOT:PSS–MXene system. The theoretical investigations revealed that the doping of PEDOT:PSS with Ti3C2Tx could cause a significant effect on the electronic properties of the HTL, as experimentally demonstrated by an increase in the electrical conductivity. Finally, the inverted PSCs employing 0.03 wt.% MXene-doped PEDOT:PSS showed an average power conversion efficiency (PCE) of 15.1%, up from 12.5% for a reference PSC employing a pristine PEDOT:PSS HTL. The champion device with a 0.03 wt.% MXene–PEDOT:PSS HTL achieved 15.5% PCE.

Single-atoms (N, P, S) encapsulation of Ni-doped graphene/PEDOT hybrid materials as sensors for H2S gas applications: intuition from computational study

“…The N_Ni@GP_PEDOT@H2S is also less compactible (with an energy of 0.8618 and an adsorption wavelength of 1438.65 nm) even though it is slightly compactible compared P_Ni@GP_PEDOT@H2S. This analysis concludes that the compatibility and adsorption potential of the studied systems are in the decreasing order of Ni@GP_PEDOT@H 2 S > S_Ni@GP_PEDOT@H 2 S > N_Ni@GP_PEDOT@H 2 S > P_Ni@GP_PEDOT@H 2 S. Compared to previous studies, the simulated interaction outshines several previous studies including Agwamba et al, 73 , Ali et al 74 , etc. that reported first excitation energy higher than 2 eV and wavelength less than 600 nm.…”

Impact of Polythiophene ((C4H4S)n; n = 3, 5, 7, 9) Units on the Adsorption, Reactivity, and Photodegradation Mechanism of Tetracycline by Ti-Doped Graphene/Boron Nitride (Ti@GP_BN) Nanocomposite Materials: Insights from Computational Study

“…The electron is delocalized when the ELF value is less than 0.5. 132 In this study, only all of the ELF values were lower than 0.5, suggesting a delocalization of electrons of the compounds.…”

“…When the ELF value is between 0.5 and 1, it indicates that there are bonding and nonbonding localized electrons in the area. The electron is delocalized when the ELF value is less than 0.5 . In this study, only all of the ELF values were lower than 0.5, suggesting a delocalization of electrons of the compounds.…”

Facile Synthesis of Novel Ti2C Nano Bipyramids for Photothermal and Photodynamic Therapy of Breast Cancer

“…Results Figure 7(a, b The as-synthesized Ti 2 C NBPs have shown absorption in UV and visible light regions as compared with previously reported Ti 3 C 2 and Ti 2 C MXene nanosheets, demonstrating that by changing the shape, the photocatalytic activity of Ti 2 C NBPs was increased. [31,20] It has been noted that the photocatalytic activity is sensitive to the size and shape of the particles, the relationship between the particle structure and the photocatalytic activity has not yet been proven. But in different particles such as Au, and TiO 2 the complicated shapes with horns and edges including nano bipyramids gives higher photocatalytic activity.…”