Hole Transport Layer Research Articles

Bright and Efficient CsSnBr3 Light-Emitting Diodes Enabled by Interfacial Reaction-Assisted Crystallization.

Tin-based perovskites are more environmentally friendly than their lead-based alternatives. Perovskite light-emitting diodes (PeLEDs) using iodide-based tin perovskites have achieved considerable advancements in efficiency. However, PeLEDs using bromide-based tin perovskites have not progressed as rapidly, primarily due to challenges in controlling their crystallization processes. Here, an interfacial reaction-assisted crystallization method is introduced to achieve bright and efficient CsSnBr3 PeLEDs. It is started by forming an intermediate phase through the coordination of SnBr2 with ethylenediamine derivatives. Subsequently, a protonation reaction is designed between the intermediate phase and the acidic polyethylenedioxythiophene: poly(styrene sulfonate) hole-transport layer to generate high-quality CsSnBr3 films. Additionally, the use of potassium thiocyanate additives effectively enhances the photoluminescence efficiency of the CsSnBr3 films. These efforts result in CsSnBr3-based PeLEDs achieving a maximum luminance of 787cdm-2 and a peak external quantum efficiency of 0.91%, demonstrating the most efficient and brightest CsSnBr3-based PeLEDs to date. This work opens an avenue to better control the crystallization of tin-based perovskite.

Hole-Transport-Layer-Free Organic Solar Cells with Enhanced Efficiency Upon Halogenated Solvent Treatment.

Typical PEDOT:PSS hole-transporting layers frequently present some issues, including mismatched energy levels, high acidity, severe hygroscopicity, etc., all of which significantly weaken device performance. Herein, an approach of halogenated solvent treatment to modulate the physical properties of indium tin oxide (ITO) substrates is employed. Four halogenated-ITO anodes (named ITO-F, ITO-Cl, ITO-Br and ITO-I) are achieved by ITO substrates immersed in hydrogen peroxide co-solvents mixed with 1,2-difluorobenzene, 1,2-dichlorobenzene, 1,2-dibromobenzene and 1,2-diiodobenzene, respectively, and upon UV illumination. The work functions of the ITO-F/Cl/Br/I anodes increase from 4.63eV for ITO to 5.30, 5.32, 5.24, and 5.28eV, respectively, which are close to 5.22eV for ITO/PEDOT:PSS. Additionally, the investigated PM6:L8-BO:BTP-eC9 devices based on various anodes showed power conversion efficiencies (PCEs) of 17.81% for ITO-F, 19.48% for ITO-Cl, 17.05% for ITO-Br, 17.34% for ITO-I and 18.70% for ITO/PEDOT:PSS, respectively. In particular, a comprehensive experimental analysis is conducted to establish connections between theoretical calculations, blend morphology and physical dynamics, and further elucidate the factors that cause differences in device efficiencies. This work manifests the advantages of the proposed halogenated ITO for realizing highly efficient organic photovoltaics.

Regulation of Interface Schottky Barrier and Photoelectric Properties in Carbon-Based HTL-Free Perovskite Solar Cells.

Carbon-based hole transport layer (HTL)-free perovskite solar cells (C-PSCs) receive a lot of attention because of their simplified preparation technology, low price, and good hydrophobicity. However, the Schottky junction formed at the interface between perovskite and carbon poles affects the photogenerated carrier extraction and conversion efficiency. In this paper, 4-trifluoromethyl-2-pyridinecarboxylic acid (TPCA) is used to modify the perovskite films. The introduction of TPCA can reduce the p-type Schottky barrier height (p-SBH) and thin the Schottky barrier width W, which greatly improves the hole transport ability and tunneling probability. Meanwhile, the n-type Schottky barrier height (n-SBH) shows a rising trend, which prevents the reverse electron transport to carbon, suppresses unnecessary carrier complexes, and greatly improves the device's optoelectronic performance. Besides, the pyridine nitrogen and C=O in TPCA interact with Pb2+ to raise the crystal quality of perovskite films while inhibiting nonradiative recombination. The results show that compared with the pristine device's 11.45% photoelectric conversion efficiency （PCE), the TPCA-modified device achieves 13.64% PCE. The device's long-term stability significantly improved post-TPCA modification. After 720h of storage at room temperature and 40-60% relative humidity in the air, the unencapsulated device retained 77% of its initial efficiency.

Charge-storage behaviors in quantum-dot light-emitting diodes

Understanding the charge dynamics in the quantum-dot light-emitting diodes (QLEDs) is essential to further improve their performance. Here we demonstrate that the holes can be stored for over 30 ms in QLEDs based Cd-based quantum dot (QD) emission layer. This ultralong-term hole storage is examined by inserting an electron-capturing unit (ECU) in the hole-transport layer. Through superimposing a negative offset voltage during transient electroluminescence measurements, the electrons captured by the ECU were transported back to the QDs, where holes are stored during the typical operation for the QLED. Then, excitons are formed and electroluminescence signal is detected. We found that the electroluminescence signal can be detected until 30 ms after turning off the driving voltage for the QLED. Given the limited electron capturing time in the ECU, this should be the lower limit for hole storage time. It is abnormal and unanticipated for the QLEDs based on the ZnO electron-transport layer, for which electrons are widely considered as the majority charge carriers. We believe our results can offer significant insights into the working mechanism and degradation of the QLEDs.

A Numerical Simulation Study of the Impact of Kesterites Hole Transport Materials in Quantum Dot-Sensitized Solar Cells Using SCAPS-1D.

Energy generation and storage are critical challenges for developing economies due to rising populations and limited access to clean energy resources. Fossil fuels, commonly used for energy production, are costly and contribute to environmental pollution through greenhouse gas emissions. Quantum dot-sensitized solar cells (QDSSCs) offer a promising alternative due to their stability, low cost, and high-power conversion efficiency (PCE) compared to other third-generation solar cells. Kesterite materials, known for their excellent optoelectronic properties and chemical stability, have gained attention for their potential as hole transport layer (HTL) materials in solar cells. In this study, the SCAPS-1D numerical simulator was used to analyze a solar cell with the configuration FTO/TiO2/MoS2/HTL/Ag. The electron transport layer (ETL) used was titanium dioxide (TiO2), while Cu2FeSnS4 (CFTS), Cu2ZnSnS4 (CZTSe), Cu2NiSnS4 (CNTS), and Cu2ZnSnSe4 (CZTSSe) kesterite materials were evaluated as HTLs. MoS2 quantum dot served as the absorber, with FTO as the anode and silver as the back metal contact. The CFTS material outperformed the others, yielding a PCE of 25.86%, a fill factor (FF) of 38.79%, a short-circuit current density (JSC) of 34.52 mA cm-2, and an open-circuit voltage (VOC) of 1.93 V. This study contributes to the advancement of high-performance QDSSCs.

MXenes in Perovskite Solar Cells: Emerging Applications and Performance Enhancements

Perovskite solar cells (PSCs) have emerged as promising candidates for next-generation photovoltaic technology due to their remarkable power-conversion efficiencies (PCEs). Since their introduction, the PCE of PSCs has advanced from 3.8% to over 26%. Nonetheless, challenges pertaining to stability and reliability continue to impede their commercial viability. Recent progress in interface engineering and materials science has underscored the potential of two-dimensional (2D) materials, particularly MXenes, in mitigating these challenges. MXenes represent a class of two-dimensional materials with significant potential for application in PSCs, attributed to their exceptional electrical conductivity, high carrier mobility, remarkable optical transparency, chemical stability, and tunable surface chemical properties. When employed as electron transport layers, MXenes enhance charge transfer and extraction efficiency, leading to substantial improvements in PCEs. Furthermore, their integration into hole transport layers and use as interfacial modifiers contribute to the mitigation of degradation pathways, thereby enhancing device longevity. The unique structural and electronic characteristics of MXenes facilitate their application as transparent electrodes, presenting opportunities for cost reduction and improved optical properties. This review provides a comprehensive overview of the current advancements in MXene-based PSCs, emphasizing significant accomplishments and exploring future research directions aimed at enhancing the efficiency and stability of these devices.

Organic Solvent-Based PEDOT:PSS Solution for Air-Processed Organic Photovoltaics.

PSS is one of the best hole transport materials in organic photovoltaics (OPV). However, due to poor wettability, the aqueous PEDOT:PSS (a-PEDOT) is not applicable for inverted structured OPV as a hole transport layer (HTL) on top of the active layer. In this work, organic solvent-based PEDOT:PSS (o-PEDOT) with improved wettability was prepared by the solvent-replacement method through centrifugal ultrafiltration, dialysis membrane, and thermal evaporation. Adopting o-PEDOT as the HTL on the top surface of the active layer, the inverted OPVs were successfully prepared through a solution process. Importantly, due to good conductivity and suitable work function, the o-PEDOT can also act as the interconnection layer (ICL) in air-processed tandem OPV devices. The tandem device achieved a champion PCE of 15%, among the best reports of solution-processed homotandem OPV under open-air conditions. The flexible tandem OPV using o-PEDOT as an ICL was also demonstrated, with an efficiency of over 14%.

Synergistic Passivation of Pyridinium Tetrafluoroborate (PyBF4) in Inverted (CsPbI3)0.05((FAPbI3)1−x(MAPbBr3)x)0.95 Solar Cells with Atomic Layer Deposited NiO Layers

Nickel oxide (NiO) is a promising hole transport layer (HTL) that can be used to fabricate efficient, large‐scale inverted‐type perovskite solar cells (PSCs). However, depositing a high‐quality perovskite layer on NiO substrates comparable to those realized in the normal structure still presents a challenge. Herein, a pyridinium tetrafluoroborate (PyBF4) additive is introduced to passivate the intrinsic defects in the bulk perovskite films. The nitrogen Lewis base in the PyBF4 molecule interacts well with uncoordinated Pb2+ cations, leading to high‐quality perovskite films with minimized defects. Meanwhile, the pseudohalide BF4− can fill halogen vacancies in the perovskite films to enable defect passivation. As a result, the perovskite precursor solution with PyBF4 shows better reproducibility for high‐efficiency devices. The optimal PSC based on PyBF4 modification yields a champion power conversion efficiency of 22.7% with atomic layer deposited NiO as the HTL.

Boosting Efficiency in Carbon Nanotube-Integrated Perovskite Photovoltaics.

Carbon nanomaterials (graphene, carbon nanotubes, and graphene oxide) have potential applications for optoelectronics, thanks to their superior electronic and optical characteristics. The remarkable stability of carbon-based perovskite solar cells (PSCs) has attracted significant attention. Herein, a fluorine-doped carbon nanotube (F-CNT) is incorporated into the PSCs as a hole-transporting layer (HTL) in between methylammonium lead iodide (MAPbI3) and the rear electrode to develop an effective MAPbI3/HTL interface. The F-CNT bridges both the MAPbI3 film and the Au electrode and promotes photocarrier extraction and transportation between the two layers. The article presents a simulation-driven optimization approach for the development of efficient CNT-based PSCs. Many factors, such as the total defect density of the perovskite, the shallow acceptor density of the F-CNTs film thickness, the perovskite thickness, parasitic resistances, and temperature, have been studied using SCAPS-1D simulations. Utilizing the photovoltaic software SCAPS-1D, we simulated defect states and interfaces to approximate a realistic perovskite device in our analyses. The CNT-based PSC with an architecture of FTO/TiO2/MAPbI3/F-CNTs/Au achieved an outstanding power conversion efficiency (PCE) of 26.91%, with a fill factor (FF) of 84.23%.

Performance of Cu-doped V2O5 thin film as a hole transport layer in perovskite-based solar cells

Abstract Herein, the performance of Cu-doped V2O5 thin film as a hole transport layer (HTL) in inverted planar (p-i-n) perovskite solar cells was reported. The structural, optical, morphological, and electrical properties of Cu-doped V2O5 thin films, with varying Cu concentrations, were analyzed using x-ray photoelectron spectroscopy, UV-Vis spectrophotometry, atomic force microscopy, Kelvin probe force microscopy, and a four-point probe system. The sheet resistance of the V2O5 HTLs decreased significantly with Cu doping, leading to an increase in the devices’ short-circuit current, which depended on the Cu concentration in the V2O5 thin films. It was demonstrated that V2O5 thin films produced using a low-temperature process can serve as a HTL in p-i-n perovskite solar cells. Furthermore, Cu doping in V2O5 thin films was shown to enhance the power conversion efficiency of the devices.

Non-toxic Cu3BiS3 thin film solar cells with Al doped TiO2 as electron-transport layers

Abstract Cu3BiS3 has been considered as an attractive photovoltaic material due to its suitable bandgap, excellent photoelectric properties, abundant component elements and low toxicity. However, most of the reported Cu3BiS3 solar cells contain toxic components in other functioning layers such as CdS in electron-transport layers (ETLs). In this study, the Cu3BiS3 thin films were prepared by spin-coating method. We find that the CuCl concentration in precursor solutions has influences on both the optical bandgap and grain size of the Cu3BiS3 thin films, thus affecting the performance of solar cells. The optimal CuCl concentration is 0.91 M. Besides, Al doped TiO2 (ATO) and MoOx films are employed as ETLs and hole-transport layers (HTLs) respectively, constructing a totally non-toxic thin film solar cell. Moreover, it is demonstrated that the ratio (R Al:Ti) of Al source (Aluminum nitrate nonahydrate) to Ti source [Titanium diisopropoxide bis(acetylacetonate)] in the precursor solution of ATO and the thickness of MoOx have significant influences on solar cells. Moderate Al doping in ATO, e.g. R Al:Ti=1:50, can produce oxygen vacancies and accelerate the interfacial charge transfer, thus resulting in the increased short-circuit current density and fill factor. With the optimized Cu3BiS3 absorber, ETL and HTL, improved cell performances are observed comparted to the spin-coated Cu3BiS3 counterparts with CdS as ETLs in literature.

Low temperature processing of hole transport layer-free CsPbI2Br solar cells assisted by SAM co-deposition

The development of inverted all-inorganic perovskite solar cells (PSCs) is limited by the high processing temperature and poor film coverage of self-assembled molecule (SAM) hole transport layer (HTL). In this work, the hot-air-assisted annealing method was utilized to prepare CsPbI2Br films at low temperature in an ambient environment. The SAM called 2–(3,6-dimethoxycarbazol-9-yl) ethyl phosphonic acid (MeO-2PACz) is added into the CsPbI2Br precursor to spontaneously form MeO-2PACz dipole layer and perovskite light absorber. The MeO-2PACz with abundant phosphate groups modulated the uncoordinated lead at the perovskite's grain boundaries via forming –P–O–Pb and –P=O–Pb bonds, which improves the crystallinity and reduces trap density of perovskite film. Furthermore, the spontaneously formed MeO-2PACz dipole layer on the ITO substrate during the perovskite film processing enhanced hole transport efficiency and reduced non-radiative recombination loss at the ITO/CsPbI2Br interface. As a result, the p-i-n HTL-free inorganic CsPbI2Br PSCs with MeO-2PACz additive achieved a power conversion efficiency of 12.92%, which is significantly higher than the reference PSCs (6.55%). This work provides an easy and efficient way to prepare efficient HTL-free all-inorganic PSCs at low temperature in an ambient environment with MeO-2PACz SAM additive.

Methylthio Substituent in SAM Constructing Regulatory Bridge with Photovoltaic Perovskites.

Inverted (p-i-n) perovskite solar cells (PSCs) have experienced remarkable advancements in recent years, which is largely attributed to the development of novel hole-transport layer (HTL) self-assembled monolayer (SAM) materials. Methoxy (MeO-) groups are typically introduced into SAM materials to enhance their wettability and effectively passivate the perovskite buried interface. However, MeO-based SAM materials exhibit a mismatch in highest occupied molecular orbital (HOMO) levels with perovskite layer due to the strong electron-donating capability of methoxy group. In this work, we introduced a methylthio (MeS-) substituent that is superior to methoxy as a highly versatile self-assembled molecular design strategy. As a soft base, sulfur atom forms a stronger Pb-S bond than oxygen. Additionally, within the CbzPh series of SAM materials, MeS-CbzPh demonstrates a more optimal HOMO level and enhanced hole transport properties. Consequently, the MeS-CbzPh HTL based device achieved an impressive power conversion efficiency (PCE) of 26.01 % and demonstrated high stability, retaining 93.3 % efficiency after 1000 hours of maximum power point tracking (MPPT). Moreover, in comparison with the commonly used 4PACz-based SAM molecular series, MeS-4PACz also exhibited the best performance among its peers. Our work provides valuable insights for the molecular design of SAM materials, offering a highly versatile functional substituent group.

Methylthio Substituent in SAM Constructing Regulatory Bridge with Photovoltaic Perovskites

AbstractInverted (p‐i‐n) perovskite solar cells (PSCs) have experienced remarkable advancements in recent years, which is largely attributed to the development of novel hole‐transport layer (HTL) self‐assembled monolayer (SAM) materials. Methoxy (MeO−) groups are typically introduced into SAM materials to enhance their wettability and effectively passivate the perovskite buried interface. However, MeO‐based SAM materials exhibit a mismatch in highest occupied molecular orbital (HOMO) levels with perovskite layer due to the strong electron‐donating capability of methoxy group. In this work, we introduced a methylthio (MeS−) substituent that is superior to methoxy as a highly versatile self‐assembled molecular design strategy. As a soft base, sulfur atom forms a stronger Pb−S bond than oxygen. Additionally, within the CbzPh series of SAM materials, MeS−CbzPh demonstrates a more optimal HOMO level and enhanced hole transport properties. Consequently, the MeS−CbzPh HTL based device achieved an impressive power conversion efficiency (PCE) of 26.01 % and demonstrated high stability, retaining 93.3 % efficiency after 1000 hours of maximum power point tracking (MPPT). Moreover, in comparison with the commonly used 4PACz‐based SAM molecular series, MeS‐4PACz also exhibited the best performance among its peers. Our work provides valuable insights for the molecular design of SAM materials, offering a highly versatile functional substituent group.

Electron-Beam-Evaporated Nickel Oxide Thin Films for Application as a Hole Transport Layer in Photovoltaics

We present the growth of nickel oxide (NiO) thin films as a hole transport material in photovoltaic devices using the e-beam evaporation technique. The metal oxide layers were reactively deposited at a substrate temperature of 200 °C using an electron beam evaporator under an oxygen atmosphere. The oxide films reactively grown through electron-beam evaporation were optimized for carrier transport layers. Optical and structural characterizations were performed using ultraviolet–visible (UV–Vis) spectrometry, X-ray diffraction, contact angle measurements, scanning electron microscopy, and Hall effect measurements. The study of these films confirmed that the NiO layer is a suitable candidate for use as a hole transport layer based on Hall effect measurements. A morphological study using field-emission scanning electron microscopy confirmed the growth of compact, uniform, and defect-free metal oxide layers. Contact angle measurements revealed that the films possessed semi-hydrophilic properties, contributing to improved stability by repelling water from their surfaces. The stoichiometry of the films was influenced by the oxygen pressure during deposition, which affected both their morphological and optical features. The NiO films exhibited a transmittance exceeding 80% in the visible spectrum. These findings highlight the potential applications of such nickel oxide films as hole transport material layers.

Numerical optimization of all-inorganic CsSnBr3 perovskite solar cells: the observation of 27% power conversion efficiency

Abstract In this research, we employed SCAPS-1D simulation software to numerically optimize the performance of four CsSnBr3-based perovskite solar cell structures. Specifically, we analyzed the FTO/ZnO/CsSnBr3/rGO/Se, FTO/AlZnO/CsSnBr3/rGO/Se, FTO/LiTiO2/CsSnBr3/rGO/Se, and FTO/WS2/CsSnBr3/rGO/Se configurations. The optimization process focused on adjusting the thicknesses of the electron transport layer, hole transport layer, and perovskite layer, while also evaluating the effects of temperature, series resistance, and shunt resistance on the Jsc, Voc, FF, and PCE. As a result, we achieved PCE of 26.92%, 26.89%, 26.89%, and 26.91% for the FTO/AlZnO, FTO/ZnO, FTO/LiTiO2, and FTO/WS2-based structures, respectively. Furthermore, the PCE obtained for all CsSnBr3-based perovskite solar cell structures outperformed the recently reported ITO/WS2/CsSnBr3/Cu2O/Au perovskite solar cell, which exhibited the highest PCE in the literature, by nearly 5%.

Optimizing electrical properties and efficiency of copper-doped CdS and CdTe solar cells through advanced ETL and HTL integration: a comprehensive experimental and numerical study

Abstract Copper is a commonly preferred dopant for cadmium telluride based solar cells. Even though it is widely used as it enhances the electrical properties, it has the tendency to diffuse into the CdTe layer as well as the CdS/CdTe junction interface which adversely affects the performance of CdTe solar cells. In this experimental study copper doping of buffer cadmium sulfide layer has been performed to analyse its effect on structural, electrical, and optical properties of CdS and CdTe layers. While from the X-ray diffraction analysis it was observed that there was reduction in peak intensities and crystallite sizes of both the CdS and CdTe layers with the increase in amount of copper dopant, from the electrical properties it was found that there were improvements in carrier concentration, mobility, and conductivity of both the layers. To mitigate the losses due to Cu doping, enhance the efficiency and stability of CdTe solar cells an extensive numerical modelling approach was undertaken to employ electron transport layers (ETL) and hole transport layers (HTL) to the copper-doped CdS/CdTe solar cells. We obtained optimum results with titanium dioxide and copper barium thiostannate as ETL and HTL respectively. Finally, CdTe-based solar cells were modelled integrating copper-doped CdS as the buffer layers, TiO2 as ETL and CBTS as HTL respectively. The obtained experimental values of Cu-doped CdS and CdTe layers were implemented into this model. This superstrate configuration yielded impressive output parameters: open circuit voltage of 1.07 V, short-circuit current density of 29.32 mA cm−2, fill factor of 85.08 %, and efficiency of 26.67 %.

High Efficiency (>10%) AgBiS2 Colloidal Nanocrystal Solar Cells with Diketopyrrolopyrrole-Based Polymer Hole Transport Layer.

Silver bismuth disulfide (AgBiS2) colloidal nanocrystals (CNCs) have emerged as ecofriendly photoactive materials with excellent photoconductivity and high absorption coefficients, in compliance with the restriction of hazardous substances (RoHS) guidelines. To maximize the theoretical potential of AgBiS2 CNC solar cells, a new diketopyrrolopyrrole (DPP)-based polymer, BD2FCT, optimized as a hole transport layer (HTL), is developed. This asymmetric thiophene-rich polymer HTL effectively complements the optical absorption spectrum of CNCs and forms a homogeneous layer atop the CNCs, facilitating favorable vertical charge transfer through intrinsic molecular packing. Furthermore, the BD2FCT HTL aligns energetically with AgBiS2, significantly reducing charge recombination at the CNC/HTL interfaces and enhancing charge extraction and photocurrent generation across the entire optical absorption spectrum. These characteristics are further optimized through precise molecular engineering. Additionally, a low-bandgap acceptor, IEICO-4F, is structurally incorporated with the BD2FCT polymer to further improve charge funneling and complementary absorption. Transient absorption spectroscopy reveals enhanced hole transfer from CNC to BD2FCT-29DPP:IEICO-4F, resulting in reduced charge recombination and efficient charge extraction. Consequently, a BD2FCT-based AgBiS2 CNC solar cell achieves a power conversion efficiency (PCE) of 10.1%, demonstrating significant improvements in short-circuit current density (JSC) and fill factor (FF).

Effects of Alkyl Spacer Length in Carbazole-Based Self-Assembled Monolayer Materials on Molecular Conformation and Organic Solar Cell Performance.

Carbazole-based self-assembled monolayer (SAM) materials as hole transport layers (HTL) have led organic solar cells (OSCs) to state-of-the-art photovoltaic performance. Nonetheless, the impact of the alkyl spacer length of SAMs remains inadequately understood. To improve the knowledge, four dichloride-substituted carbazole-based SAMs (from 2Cl-2PACz to 2Cl-5PACz) with spacer lengths of 2-5 carbon atoms is developed. Single crystal analyses reveal that SAMs with shorter spacers exhibit stronger intermolecular interactions and denser packing. The molecular conformation of SAMs significantly impacts their molecular footprint and coverage on ITO. These factors result in the highest coverage of 2Cl-2PACz and the lowest coverage for 2Cl-3PACz on ITO. OSCs based on PM6:L8-BO with 2Cl-2PACz as HTL achieved high efficiencies of 18.95% and 18.62% with and without methanol rinsing of the ITO/SAMs anodes, corresponding to monolayer and multilayer structures, respectively. In contrast, OSCs utilizing the other SAMs showed decreased efficiencies as spacer length increased. The superior performance of 2Cl-2PACz can be attributed to its shorter spacer, which reduces series resistance, hole tunneling distance, and barrier. This work provides valuable insights into the design of SAMs for high-performance OSCs.

Strategic design of carrier transport layer-free homojunction perovskite photodetector

Abstract Perovskite photodetectors (PPDs) have attracted extensive attention due to their unique material properties. However, the use of electron and hole transport layers ( ETLs and HTLs) significantly increases the complexity of design and processing and reduces the reliability of the devices. To address these issues effectively, a simple strategy of eliminating the ETLs and HTLs by employing a perovskite homojunction is proposed. In this study, we examine a numerical design of p-n homojunction-based PPD without the use of carrier transport layers (CTLs), using the Silvaco TCAD simulator. To unlock the potential of the proposed design, the effects of doping concentration, mobility, thickness, and bandgap of p-perovskite and n-perovskite on the PPD photoelectric characteristics are investigated and optimized. The simulation results illustrate that a high-performance CTL-free PPD can be achieved by forming a p-n homojunction using a thin (<200 nm) highly-doped (5 × 1017 cm−3) p-perovskite layer and a thick (>600 nm) lowly-doped (5 × 1014 cm−3) n-perovskite layer with suitable mobility (1 ∼ 10 cm2 V−1 s−1). Under optimized conditions, our findings reveal an optimum detectivity of 7.4 × 1013 Jones at 750 nm, the optimum responsivity is found to be 0.42 A W−1 at 675 nm and the optimum EQE is 84% at 475 nm. These results highlight the promising potential of the p-n homojunction design as a device configuration for producing high-performance and reliable commercial PPDs without any CTL.