Fluorinated copper phthalocyanine as an electron transport material in perovskite solar cell

Abstract

Summary The state‐of‐art charge transport materials, TiO2 and Spiro‐OMeTAD suffer from various drawbacks such as instability, lengthy fabrication procedure and low charge mobilities. In this paper, we have studied copper phthalocyanine (CuPc) and halogen‐substituted copper phthalocyanine (X16CuPc; X = F, Cl, Br, I) through density functional theory (DFT) and determined their ground state properties, excited state properties and solubility in DMSO (widely used solvent in the fabrication of perovskite solar cell [PSC]). We have shown that fluorinated copper phthalocyanine(F16CuPc) acts as an electron transport layer (ETL) and CuPc acts as a hole transport layer (HTL) in MAPbI3‐based PSC. The moisture stability of CuPc and F16CuPc has been established and it has been shown that CuPc and F16CuPc will protect the perovskite layer from degradation due to the presence of moisture in the surroundings. Using the properties obtained via DFT, PSC has been simulated using SCAPS, and it is established that CuPc as hole transport material and F16CuPc as electron transport material gives better efficiency compared with the state of art charge transport materials (TiO2 and Spiro‐OMeTAD). The device has been optimized with respect to (w.r.t.) thickness, doping concentration, defect density and interface defect density. We have studied the effect of series resistance, shunt resistance and temperature on the performance of PSC and this configuration has shown good thermal stability. Carbon has been proposed as an alternative to gold as the back contact thereby making our device more economical. The optimized device showed quantum efficiency of (81.59% to 98.69%) in the visible region. A fill factor of 79.01%, power conversion efficiency of 22.30% has been obtained.

Phthalocyanine in perovskite solar cells: a review

“…In a recent study, CuPc and F 16 CuPc were studied as hole and electron transport layers in an MAPI 3 -based PSC device, respectively, through DFT calculations and compared to the state-of-art charge transport materials TiO 2 and spiro-OMeTAD, suggesting that better efficiency can be achieved for the Pc-based device. 149 The device simulation study showed that an FF of 79.01% and PCE of 22.30% can be expected for this PSC device. In 2022, iron(II)-2,9,16,23-tetraamino-phthalocyanine (FeTAP) (73) was used as an additive inside a mixed-halide perovskite layer to passivate the defects at the surface and grain boundaries through the formation of strong bonds between the unsaturated Pb 2+ ions and N-H moieties.…”

P3CPenT as an organic hole transport layer for perovskite solar cells

“…The charge carrier hopping is facilitated by lower values of reorganization energies, as proposed by the Marcus theory [41] that is, lower the values of reorganization energies, better is the carrier hoping and easier the charge transport. An efficient HTL should have a low value of hole reorganization energy ( λ hole ) to aid the flow of holes and at the same time have a high value of electron reorganization energy ( λ ele ) to hinder the flow of electrons [10]. Likewise, an efficient ETL should have a low value of electron reorganization energy ( λ ele ) to aid the flow of electrons and at the same time have a high value of hole reorganization energy ( λ hole ) to hinder the flow of holes [10].…”

“…An efficient HTL should have a low value of hole reorganization energy ( λ hole ) to aid the flow of holes and at the same time have a high value of electron reorganization energy ( λ ele ) to hinder the flow of electrons [10]. Likewise, an efficient ETL should have a low value of electron reorganization energy ( λ ele ) to aid the flow of electrons and at the same time have a high value of hole reorganization energy ( λ hole ) to hinder the flow of holes [10]. It is observed from Table 2 that the λ hole of P3CPenT is low and the λ ele is higher indicating that P3CPenT aids the hole transport and suppress the electron transport.…”

“…As discussed in the introduction section, the perovskite absorber layer MAPbI 3 decomposes to MAI and PbI 2 on interaction with moisture, which leads to the degradation of PSC in the ambient air. This can be avoided if the absorber is sandwiched between the CTLs, which are hydrophobic in nature, which will prevent the contact of moisture with the absorber [10]. In order to examine whether the P3CPenT oligomer is hydrophobic or not, we optimize the P3CPenT oligomer structure with water molecules at different locations.…”

“…The quality of atomization energies obtained from CAMB3LYP and B3LYP are similar but, charge transfer excitations are performed better in CAMB3LYP and underestimated in B3LYP [20]. The optical bandgap which is the excitation energy of the lowest excited state ( E EX ) [22] and the exciton binding energy ( E B ) which is the difference between the electronic and optical bandgap [10] is calculated. The solubility of P3CPenT in dimethyl sulfoxide (DMSO) solvent is calculated by utilizing a conductor‐like polarizable continuum model (CPCM) [23].…”