Hole Accumulation Research Articles

An Efficient Solution‐Processed Interconnecting Layer for Large‐Area Tandem Organic Solar Cells

Interconnecting layer (ICL) is a key part of the tandem organic solar cells (OSCs) to achieve high efficiency. The ICLs of efficient inverted nonfullerene OSCs are complicated that comprise vacuum‐deposited MoO3, solution‐processed ZnO, and an additional thin silver (or PEDOT:PSS) film in between. Herein, an efficient fully solution‐processed ICL is first reported that comprises a PEDOT:F layer and a ZnO layer. The PEDOT:F is short for poly(3,4‐ethylenedioxythiophene):perfluorinated sulfonic acid ionomer that is alcohol dispersed and has a work function of 5.6 eV for hole collection. The ZnO is used for electron collection. The PEDOT:F/ZnO has a conductivity of 2.28 × 10−3 S cm−1 which can play a recombination zone. The solution‐processed ICL of PEDOT:F/ZnO has been validated in both two‐junction and triple‐junction solar cells. The tandem cells show high fill factor (FF) of 76–80% and high open‐circuit voltage (VOC) which is nearly the sum of the single‐junction OSCs. The PEDOT:F/ZnO ICL has also been used to fabricate large‐area tandem organic module (15.48 cm2) that shows a VOC of 10.25 V, FF of 75.1%, and a power conversion efficiency of 13.24%. The PEDOT:F/ZnO is a promising ICL for high‐performance tandem OSCs.

Archetype-Cation-Based Room-Temperature Ionic Liquid: Aliphatic Primary Ammonium Bis(trifluoromethylsulfonyl)imide as a Highly Functional Additive for a Hole Transport Material in Perovskite Solar Cells.

Room-temperature ionic liquids (RTILs) have attracted significant attention owing to their unique nature and a variety of potential applications. The archetypal RTIL comprising an aliphatic primary ammonium was discovered over a century ago, but this cation is seldom used in modern RTILs because other bulky cations (e.g., quaternary ammonium-, pyridine-, and imidazole-based cations) are prominent in current major applications, such as electrolytes and solvents, which require low and/or reversible reactivities. However, although the design of materials should change according to the intended application, RTIL designs remain conventional even when applied in unexplored fields, limiting their functions. Herein, RTIL consisting of an archetypal aliphatic primary ammonium (i.e., n-octylammonium: OA) cation and a modern bis(trifluoromethylsulfonyl)imide (TFSI) anion is proposed and demonstrated as a highly functional additive for a 2,2',7,7'-tetrakis(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD), which is the most common hole transport material (HTM), in perovskite solar cells (PSCs). The OA-TFSI additive exhibits prominent functions via permanent reactions of the component ions with the PSC components, thus providing several advantages. The OA cations spontaneously and densely passivate the perovskite layer during the HTM deposition process, leading to both suppression of carrier recombination at the HTM/perovskite interface and hydrophobic perovskite surfaces. Meanwhile, the TFSI anions effectively improve the HTM function most likely via efficient stabilization of the Spiro-OMeTAD radical, enhancing hole collection properties in the PSCs. Consequently, PSC performances involving long-term stability were significantly improved using the OA-TFSI additive. Based on the present results, this study advocates that reconsidering the RTIL design, even when it differs from the current major designs yet is suitable for a target application, can provide functions superior to conventional ones. The insights obtained in this work will spur further study of RTIL designs and aid the development of the broad materials science field including PSCs.

Interface Interaction Enhanced Piezo‐Catalytic Hydrogen Peroxide Generation via One‐Electron Water Oxidation

AbstractPiezo‐catalysis, which is possible to utilize natural mechanical energy, is an ideal technology for synthesizing hydrogen peroxide (H2O2) but is still challenging. Herein, C‐layer coated ZnO (C‐ZnO) with modulated electronic structure is constructed for piezo‐catalytic H2O2 generation. The C‐layer not only provides more active sites but also induces higher piezo‐response to mechanical stimuli. As a result, the optimized C‐ZnO exhibits ultrahigh piezocatalytic activity for H2O2 yield with a rate of 294 µM h−1 in pure water. Theoretical calculation demonstrates that the interaction at the interface induces charge redistribution, leading to the hole accumulation on the surface, thus promoting one‐electron water oxidation. In addition, the C‐ZnO exhibits excellent piezo‐catalytic performance for the degradation of different pollutants. This study not only provides a promising way (utilization of mechanical energy) for efficient H2O2 production in pure water but also opens a new avenue for designing highly active piezo‐catalytic systems for pollutants degradation.

Observation of Support-Dependent Water Oxidation Kinetics on Molecularly-Derived Heterogeneous Ir-Oxide Catalysts

Heterogeneous water oxidation catalysis is central to the development of renewable energy technologies. Understanding the material properties that determine water oxidation activity is critically important for the design of efficient and durable water oxidation catalysts. The electronic structure and surface chemistry of the catalyst influence the accumulation of oxidative charge (holes) on catalytically active sites. Hole distribution dynamics and molecular structure of the active sites are generally accepted to jointly determine activity. However, these properties are typically inherent to materials; it has been difficult to independently tune them on most heterogeneous catalysts, hindering the development of an understanding of their relative influence. Herein, heterogenized dinuclear Ir catalysts (Ir-DHC) supported on different oxides were employed to overcome this challenge. It was found that at low temperatures (288-298 K), the photocatalytic activities of Ir-DHC on indium tin oxide (ITO) and CeO2 supports are comparable within the studied range of fluences (62-151 mW/cm2). By contrast, at higher temperatures (310-323 K), Ir-DHC on ITO exhibits a ∼100% higher water oxidation activity than on CeO2. The divergent activities under these conditions were attributed to the distinct abilities of the supporting substrates to redistribute surface holes. Specifically, ITO is relatively efficient in distributing photogenerated holes between Ir-DHC active sites, whereas CeO2 exhibits sluggish hole redistribution because of its reducibility, thereby limiting hole accumulation at Ir-DHC active sites. The temperature dependence was explained by a temperature induced switch in the rate-determining step of the reaction. These findings highlight the critical role of the supporting substrate in determining the turnover at active sites of heterogeneous catalysts.

Efficiency Enhancement of Wide Bandgap Lead Perovskite Solar Cells with PTAA Surface-Passivated with Monomolecular Layer from the Viewpoint of PTAA Band Bending.

This report is on the efficiency enhancement of wide bandgap lead halide perovskite solar cells (WBG Pb-PVK PSCs) consisting of FA0.8Cs0.2PbI1.8Br1.2 as the light-harvesting layer. WGB Pb-PVK PSCs have attracted attention as the top layer of all perovskite-tandem solar cells. Poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), a conductive polymer, is always used as the hole transporting layer (HTL) for Pb-PVK PSCs. Nevertheless, the hydrophobic surface of the PTAA sometimes destroys the growth of the FA0.8Cs0.2PbI1.8Br1.2 film. On the other hand, the Fermi level of PTAA is not well matched with that of perovskite film. Thus, the PCE of the WBG Pb-based PSCs with PTAA as the HTL was not very high. In this report, the efficiency of the FA0.8Cs0.2PbI1.8Br1.2 is improved by passivating the surface of the PTAA with a monomolecular layer, where the surface becomes hydrophilic, and the band bending of the PTAA layer is improved to cause swift hole collection. Finally, WBG Pb-PVK PSCs (1.77 eV) with 16.52% efficiency are reported.

Ionizing Radiation Effects on Hole Collection Backside-Illuminated p-Type Deep-Trench-Pinned Photo-MOS Pixels Under Image Acquisition

Dark current degradation, origins, and annealing behavior after x-ray irradiation are studied in a P-type, hole collecting, backside-illuminated image sensor currently being developed at STMicroelectronics and based on deep-trenched photo-MOS pixels. Different biasing conditions during irradiation, i.e. grounded or biased and sequenced, are compared. The dark current increase with total ionizing dose (TID) and the dark current annealing behavior seem to be driven by the backside interface between the P-epitaxy of the pixels and the ONO stack. Despite still being under development, this pixel architecture already exhibits both very good electro-optical performance and a better radiation hardness than pinned photodiode-based CMOS Image sensors that benefit from the same advanced CIS processing technologies. At high total dose range, the photogate challenges custom Radiation-Hardened-by-Design photodiodes by exhibiting a comparable radiation tolerance while bringing new features such as high-resolution or Correlated Double Sampling.

Self‐Powered Perovskite Photodetector Arrays with Asymmetric Contacts for Imaging Applications

AbstractDesigning photodetectors (PDs) with fast response and low power consumption is important for the realization of photoelectric conversion in photoelectric integrated systems. The emerging metal halide perovskite is proven to be a promising material for PD array devices due to its excellent photoelectric performance and large‐area production. However, the array integration of self‐powered perovskite PDs still faces challenges due to the incompatibility between perovskite and micro‐nano processing, hindering practical applications. Here, a perovskite‐compatible device fabrication process is reported for the construction of a perovskite PD array (10 × 10 pixels) with asymmetric contacts, enabling self‐powered photodetection and high‐performance imaging applications. Au and ITO/ZnO electrodes are deposited on the substrate in sequence as the asymmetric contacts. Patterned CH3NH3PbI3 films with uniform and pinhole‐free morphology are then synthesized by a photolithography‐assisted vapor–solution fabrication method as the photosensitive material. The introduction of asymmetric electrodes enables the easy collection of holes at the Au electrode side and electrons at the ITO/ZnO electrode side with light irradiation, resulting in self‐powered photodetection performance. Moreover, the PD array exhibits a uniform distribution of light response and is successfully demonstrated for light imaging. This work opens up a new avenue to develop large‐scale high‐performance perovskite optoelectronic devices with low power consumption.

Development of high-performance organic photodetectors by understanding origin of dark current density with synthesis of photoconductive polymers

Photoconductive polymers (PCPs) are key materials that determine the static and dynamic performance of p-n bulk heterojunction organic photodetectors (OPDs). Herein, we developed benzo[1,2-d:4,5-d']bis(oxazole)-based novel PCPs with π-spacer molecular engineering to promote charge-transport while maintaining low dark-current densities (Jd) in OPDs. The origin of Jd was elucidated by measuring hole charge-transfer (CT) state energy. We found that the degree of hole accumulation at the CT state rather than the CT state energy was crucial to maintaining a low Jd and promoting a fast signal response in the devices. The optimized OPDs showed highly promising responsivity (R) of 0.43 A/W and specific detectivity (D*) of 6.85 × 1012 Jones at −1 V under 532 nm LED (5.0 mW cm−2) illumination, which are superior to those of the control device (R = 0.29 A/W and D* = 5.46 × 1011 Jones). In addition, the dynamic properties were significantly improved by the introduction of π-spacers on the PCPs. −3 dB cut-off frequency was 200.4 kHz, and the rising and falling response times was ultrafast as 2.3 and 2.8 μs, respectively. Understanding the origin of Jd through the molecular engineering of PCPs is expected to contribute greatly toward expanding the knowledge required to develop high-performance OPDs.

Organic Solvent Dispersible MXene Integrated Colloidal Quantum Dot Photovoltaics

AbstractDespite recent advances in colloidal quantum dot (CQD) photovoltaics, several challenges persist and hinder further improvements. In particular, the Fermi level mismatch between the iodide‐treated photoactive and thiol‐treated hole‐transporting CQD layers creates an unfavorable energy band for hole collection. Furthermore, the numerous surface cracks in the thiol‐treated CQD layer facilitate direct contact between the photoactive CQD layer and the metal electrode, consequently leading to reduced device performance. To address these issues, a polycatechol functionalized MXene (PCA‐MXene) that can serve both as a dopant and an interlayer for CQD photovoltaics is developed. By achieving a uniformly dispersed mixture in a butylamine solvent, PCA‐MXene enables the effective combination of MXene and CQDs. This results in the modification of the work function of CQDs and the modulation of the energy band alignment, ultimately promoting enhanced hole extraction. Moreover, the PCA‐MXene employed as an interlayer effectively covers the surface cracks present in the thiol‐treated CQD layer. This coverage inhibits both metal electrode penetration and moisture intrusion into the device. Owing to these advantages, the CQD photovoltaics incorporating PCA‐MXene achieve a power conversion efficiency (PCE) of 13.6%, accompanied by enhanced thermal stability, in comparison to the reference device with a PCE of 12.8%.

Enhanced Charge Balance for Efficient Electroluminescence from Cesium Copper Halides.

Cesium copper halides have the advantages of high photoluminescence quantum efficiency and good stability, making them attractive for replacing toxic lead halides in the field of perovskite light-emitting diodes (LEDs). However, due to their shallow conduction band and the lack of electron transport layers compatible with it, it remains a great challenge to achieve charge balance in LED devices. This drawback manifests as the accumulation of holes at the interface between the emitting layer and electron transport layer, resulting in nonradiative recombination. Here, we demonstrate an effective approach to address this issue by suppressing hole injection, which is realized through modification of the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) layer with polyethylenimine. This leads to cesium-copper-halide LEDs with a high external quantum efficiency of 5.6%, representing an advance in device architecture for efficient electroluminescence from cesium copper halides.

P-type trench gate based drain-extended N-type MOS design for high unclamped inductive switching reliability

The drain-extended NMOS (DeNMOS) is a low-voltage power MOSFET. It comprises intrinsic parasitic BJT (P-BJT), which can trigger under the influence of lattice heating or avalanche-generated holes. The parasitic bipolar current and self-heating effect (SHE) facilitates the second breakdown phenomena near the drain. Hence, we proposed DeNMOS with a P-type trench gate (PTG) placed between the body and source contact to optimize the P-BJT and SHE at high current conditions using the Sentaurus TCAD simulator tool. The PTG increases hole accumulation within the P-body region to optimize the bipolar effect. Furthermore, the proposed DeNMOS (PTG_DeNMOS) structure incorporates an additional heat dissipation path, improving the thermal stability of the device. It is shown that mitigating the P-BJT enhances the device avalanche ruggedness and unclamped inductive switching (UIS) reliability at high current conditions. The analyzed results show that the proposed PTG_DeNMOS ensures UIS reliability at a peak current density 35% higher than the conventional DeNMOS (C_DeNMOS) without compromising mixed signal performance.

Fast solvent evaporation of phase pure CuBi2O4 photocathodes for photoelectrocatalytic water splitting

P-type metal oxide semiconductor CuBi2O4 exhibits excellent energy band structures and photoelectric response characteristics, which are critical for photoelectrocatalytic water splitting. However, the photocurrent densities are still well below the theoretical limit due to poor charge carrier separation and transport properties. In this work, we report a synthetic method for the preparation of phase-pure CuBi2O4 photocathode films via spray pyrolysis by adjusting the evaporation rate of the atomized droplets. An increase in the evaporation rate of the solvent may fix the structure of the deposited film faster and decrease the time available for the establishment of the segregation gradient, thus producing phase-pure semiconductor films. This method reduces process complexity and cost, and the applicability of spray pyrolysis for the preparation of phase-pure CuBi2O4 films is also confirmed. In addition, the photoelectrochemical evaluation of the samples prepared under different treatment conditions reveals that hole transport critically affects the photoelectrocatalytic performance of CuBi2O4 photocathodes. CuO can be used as a hole transport layer to promote the collection and transfer of holes and reduce the recombination of photogenerated carriers.

Minority carrier diffusion length in interface-confined PbS colloidal quantum dot (CQD): Effect of CQD surface modification on diffusion length in ultrathin PbS CQD films

Photocurrent microscopy (PCM) is a versatile tool for probing charge carrier transport associated with energy band bending at an interface. For the first time, we report the ligand-dependent electronic properties of interface-confined colloidal quantum dots (CQDs) near a metal electrode and gate dielectric layers using ultrathin lead sulfide (PbS) CQD films embedded in field effect transistors (FETs). We have compared the minority carrier (electron) diffusion length (MCDL) of ultrathin PbS CQD films treated with 1,2-ethanedithiol (EDT) and ammonium sulfide ((NH4)2S) using a bottom-contact FET structure in combination with PCM. We found that the MCDL was greater in the EDT-treated PbS CQDs than in the (NH4)2S-treated PbS CQDs. The MCDL at the 2D carrier accumulation layer was observed to depend on the concentration of the majority carrier (hole). During effective electrical channel formation by electrical gating, the MCDL decreased with hole accumulation (decreasing gate voltage) in the p-channel (NH4)2S-treated PbS CQD FET, whereas it remained similar in the EDT-treated PbS CQD FET. The effect of the majority carrier concentration on the MCDL was more pronounced in the (NH4)2S-treated sample than in the EDT-treated sample. The difference in the MCDL is attributed to a difference in the surface trap density caused by different ligand treatments.

Drift diffusion modelling of cell parameters effect on the performance of perovskite solar cells with MXene as additives

Perovskite Solar Cells (PSCs) are one of the most promising photovoltaic technologies, with rapid efficiency improvement in a short time. In recent years PSCs attained a maximum efficiency of nearly 30 %. The ability to fine-tune the performance of the perovskite layer through additives and surface modifications has been a significant factor in its recent development. A few key parameters influence the efficiency of PSCs and one such crucial parameter is the surface recombination, which needs to be minimized to improve the efficiency. This work has demonstrated that the surface recombination can be minimized by adding Ti3C2 MXene in the MAPbI3 layer of the PSCs. The addition of MXene helps increase the collection of holes from HTL, thereby reducing the recombination rate and improving cell efficiency. The substitution of MXene into the layers was simulated using SCAPS-1D software, and the results were calculated. Various potential ETL, Active layer material combinations and counter electrodes were incorporated into the simulation and the results were compared. This work can provide valuable insight into selecting suitable materials for practical research on PSCs.

Popcorn-like ZnCdS-based nanospheres with hierarchical tandem heterojunctions synergy for efficient photocatalytic performance

Heterojunction engineering is widely recognized as one of the most effective strategies for enhancing photocatalytic performance and suppressing photocorrosion by promoting efficient carrier separation and transfer. In this work, popcorn-like ZnCdS-MoS2@Co3O4 nanospheres with large specific surface areas and hierarchical tandem heterojunctions were synthesized via one-pot in-situ self-assembly combined with hole-driven photodeposition. Based on the highly uniform dispersion of MoS2 as an electron collector in the system and precise deposition of Co3O4 as a photogenerated hole collector driven by photogenerated carriers at the hole enrichment position, it can efficiently catalyze the photocatalytic hydrogen evolution in water. Compared to ZnCdS, the optimized ZCS-M@0.5C exhibits a 50-fold increase in visible-light-driven hydrogen evolution efficiency, achieving 18.73 mmol·h−1·g−1 and maintaining stability after a 20-hour cycle test. Additionally, the apparent quantum yield reaches a remarkable 10.11% at 420 nm. Experimental characterization tests and differential charge density analysis have confirmed the efficient ability of Pt-like MoS2 to induce electron separation and transportation, while p-type semiconductor Co3O4 accumulates holes through the p-n junction. Both theoretical and experimental evidence show that the incorporation of dual-internal electric fields facilitates bi-directional charge separation and rapid transfer. The photocatalytic performance is improved through a synergistic effect involving hierarchical tandem heterojunctions. This work presents a novel approach to fabricating highly efficient photocatalysts with multi-heterojunctions through synergistic effects.

Oxide Electric Field-Induced Degradation of SiC MOSFET for Heavy-Ion Irradiation

This work presents an experimental study of heavy-ion irradiation with different particle linear energy transfer (LET), gate biases, and drain biases. The results reveal that when the irradiation biases are low, the SiC MOSFET does not experience single event effect (SEE) and the electrical properties remain unchanged (the devices are in the safe operating area (SOA)). However, the oxide breakdown voltage of the device is significantly decreased due to the latent damage generated by the irradiation. The experimental results, along with TCAD simulations, suggest that the latent damage induced by the irradiation in the gate oxide is closely related to the peak electric field in the gate oxide at the time of particle incidence. This peak electric field is determined by the potential difference between the two sides of the gate oxide, which is affected by the particle LET, gate biases, and drain biases together. The high potential is determined by the combined effect of the LET and the drain-source voltage. The impact ionization of the particle by the applied electric field causes the accumulation of holes in the JFET oxide, which leads to a decrease in the doping of the N− epitaxial layer and eventually causes a rise in the high potential near the JFET oxide. The low potential is determined by the gate bias, and the negative bias applied to the gate can further increase the potential difference between the two sides of the oxide, causing an increase in the peak electric field in the gate oxide and aggravating the gate oxide damage.

Direct Z-scheme high-entropy metal phosphides/ZnIn2S4 heterojunction for efficient photocatalytic hydrogen evolution

Photocatalytic hydrogen evolution is a reliable way to mitigate the energy crisis. In this work, ZnIn2S4, which has great development prospects, is selected as the photocatalyst for photocatalytic hydrogen evolution. At the same time, in order to improve the photocatalytic hydrogen evolution performance of ZnIn2S4, a novel high-entropy metal phosphide (HEMP) catalyst with abundant active sites was compounded with ZnIn2S4. The designed direct Z-scheme HEMP/ZnIn2S4, heterojunction demonstrated outstanding photocatalytic activity and superior stability for photocatalytic hydrogen evolution. The 10% HEMP-0/ZnIn2S4 sample exhibited the best photocatalytic performance with a hydrogen evolution rate of 4630.21 μmol h−1 g−1, which is 3.29 times higher than that of pure ZnIn2S4. The excellent photocatalytic activity could be attributed to the accelerated reaction kinetics, the accumulation of electrons and holes with strong reduction and oxidation abilities and the inhibition of photogenerated electron-hole pairs of the Z-scheme heterojunction. This work achieved the first application of high-entropy metal phosphides in the field of photocatalysis, not only offering a new strategy to optimize the photocatalytic hydrogen evolution performance of ZnIn2S4 but also paving the way for the application of high-entropy materials in photocatalysis.

Revealing the Importance of Hole Transfer: Boosting Photocatalytic Hydrogen Evolution by Delicate Modulation of Photogenerated Holes

Photocatalytic hydrogen evolution (PHE) has gained massive attention for the development of renewable resources. Currently, prominent and stable PHE is still restricted by the limited utilization of photocatalytic charge carriers, especially holes, of which the transfer rate is approximately two to three orders of magnitude slower than that of electrons. Although it is widely accepted that surface holes can be consumed by electron donors, the rational design of photocatalysts to speed up hole transfer and understand the ultrafast photodynamics as well as the exploration of the effect of oxidation products is still highly urgent. Herein, cadmium sulfide (CdS), as the model photocatalyst, is investigated for prominent PHE based on hole modulation strategies. To accelerate the surface reaction, H2S-saturated Na2S&Na2SO3 solution, which outperforms traditional hole scavengers, is selected to remove the holes accumulating on the photocatalyst surface, while the oxidative cocatalyst palladium sulfide (PdS) is simultaneously impregnated on CdS to optimize the hole transfer process. Evidenced by femtosecond transient absorption spectroscopy (TAS) and band structure analysis, the ultrafast process (1–5 ps) highly related with hole transfer from CdS to PdS is proved in the CdS/PdS composite. More importantly, density functional theory (DFT) calculation suggests that the hole accumulation site (PdS) is also the oxidation active site where the active species (HS*) adsorbs on. Finally, the oxidation product composition is analyzed through Fourier transform infrared (FTIR) spectroscopy, which indicates that the colorless and value-added product S2O32– protects the photocatalyst from the light shielding effect. Contributed by factors mentioned above, improved PHE efficiency (∼145.9 mmol·g–1·h–1) is achieved on the CdS/PdS composite.

Characterization of diamond radiation detector with B-doped/undoped stacked structure

In this study, a radiation detector made of polycrystalline diamond was characterized by neutron and alpha particle. The detector consisted of a boron (B)-doped/undoped stacked structure, where the alpha particles were irradiated from the B-doped layer side. Radiation signals obtained by the multichannel analyzer were compared, and bias dependence was investigated. Results indicate that the formation of the B-doped layer modifies band structure at B-doped/undoped interface, which improving signal hole collection.

Effects of metal bis(trifluoromethanesulfonyl)imides as dopants of a hole-transporting tercarbazole compound on the photovoltaic performance of solid-state dye-sensitized solar cells

A mixture of 3,3′′,6,6′′-tetrakis(1,1-dimethylethyl)-9′-ethyl-9,3′:6′,9′′-ter-9H-carbazole (TerCz) and 1-methyl-3-propylimidazolium iodine (MPII) was utilized as a hole transporter for solid-state dye-sensitized solar cells (DSSCs). The power conversion efficiency of a solid-state DSSC with magnesium(II) bis(trifluoromethanesulfonyl)imide (MgTFSI2)-doped TerCz/MPII layer was over 70% higher than that of a reference cell with LiTFSI dopant. Superior hole collection and electron injection efficiencies were achieved in the DSSC with the MgTFSI2 dopant, resulting in a much higher short-circuit current than that of the reference device. By doping MgTFSI2, a higher fill factor was also recorded due to a lower series resistance than that of the reference cell.