Efficient Charge Injection Research Articles

Polarization-mediated electronic characteristics in Sc2CO2-based 2D metal-ferroelectric heterostructures.

The preparation of two-dimensional (2D) monolayer Sc2CO2 ferroelectric semiconductor materials provides a promising material candidate for the development of high-performance electronic devices. However, the Schottky barrier present at the electrode/Sc2CO2 interface significantly hinders the efficiency of charge injection. In this work, we propose the utilization of 2D metallic materials as electrodes to form van der Waals (vdW) contacts with ferroelectric Sc2CO2 monolayers, aiming to achieve reduced Fermi-level pinning (FLP) at the interface. By leveraging the ferroelectric polarization reversal in Sc2CO2, we demonstrate a controllable transition from Schottky to Ohmic contact, which is critical for optimizing charge injection efficiency. Additionally, we systematically investigate the polarization-mediated electronic properties of 2D metal/Sc2CO2 interfaces through first-principles calculations.The findings indicate that a transition from Schottky to Ohmic contact can be induced within these heterostructures by manipulating the polarization reversal of Sc2CO2 ferroelectric layers. Notably, the NbS2/Sc2CO2 heterojunction, particularly in the upward polarization state, exhibits the highest carrier tunneling probability among the investigated heterojunctions, making it an optimal electrode for Sc2CO2. These findings are essential for regulating Schottky barriers in 2D metal/ferroelectric semiconductor heterostructures and provide theoretical guidance for designing high-performance field-effect transistors based on 2D metal/Sc2CO2 van der Waals heterostructures.

Effective Factors for Optimizing Metallophthalocyanine-Based Optoelectronic Devices: Surface—Molecule Interactions

As a promising structure for fabricating inorganic—organic-based optoelectronic devices, metal—metallophthalocyanine (MPc) hybrid layers are highly important to be considered. The efficient charge injection and transport across the metal/MPc interface are strictly dependent on the precise molecular orientation of the MPcs. Therefore, the efficiency of MPc-based optoelectronic devices strictly depends on the adsorption and orientation of the organic MPc on the inorganic metal substrate. The current review aims to explore the effect of the terminated atoms or surface atoms as an internal stimulus on molecular adsorption and orientation. Here, we investigate the adsorption of five different phthalocyanine molecules—free-based phthalocyanine (H2Pc), copper phthalocyanine (CuPc), iron phthalocyanine (FePc), cobalt phthalocyanine (CoPc), vanadyl phthalocyanine (VOPc)—on three metallic substrates: gold (Au), silver (Ag), and copper (Cu). This topic can guide new researchers to find out how molecular adsorbance and orientation determine the electronic structure by considering the surface–molecule interactions.

Tuning surface hydrophilicity of a BiVO4 photoanode through interface engineering for efficient PEC water splitting.

This study presents a novel approach to enhance photoelectrochemical (PEC) water oxidation by integrating cobalt phthalocyanine (CoPc) with bismuth vanadate (BVO) via a direct solvothermal method. The as-prepared BVO@CoPc photoanode demonstrated a photocurrent density of 4.0 mA cm-2 at 1.23 V vs. RHE, which is approximately 3.1 times greater than that of the unmodified BVO, and has superior stability. The incident photon-to-current conversion efficiency (IPCE) of the BVO@CoPc photoanode reaches an impressive value of 81%, accompanied by significant enhancements in charge injection efficiency. This excellent performance can be ascribed to the enhanced hydrophilicity with the BVO/CoPc interface engineering, which facilitates interfacial interaction between the electrode and electrolyte, accelerates photogenerated charge carrier transfer and separation. Furthermore, compared to the immersion and drop-casting methods, the BVO@CoPc-S composite photoanode prepared via the solvothermal method exhibits a significant improvement in interfacial contact and surface hydrophilicity. These findings highlight the potential of the strategy based on interfacial hydrophilicity modification to overcome key limitations in PEC water splitting, providing a pathway to more efficient and durable photoanode design.

Dual (oxy)hydroxide Cocatalyst Synergistically Boosts Solar Water Splitting of BiVO4 Photoanode.

Bismuth oxide (BiVO4) is considered one of the most promising semiconductors for photoelectrochemical (PEC) water splitting due to its highly theoretical photocurrent of 7.5 mA cm-2. However, its sluggish kinetics and severe photocorrosion still hinder the real application of a large-area BiVO4 photoanode. Herein, a room-temperature immersion method has been used to fabricate a dual cocatalyst-coated BiVO4 film, namely the BiVO4/FeOOH/Co(OH)2 photoanode. This composite photoanode delivers a photocurrent density of 2.56 mA cm-2, which is 2.7 times that of pure BiVO4. After a long-term testing of 10 h, its retention rate of photocurrent reaches 71.63 %, which is 4.6 times that of BiVO4. The kinetic studies illustrate that dual cocatalyst can significantly lower the charge transfer resistance, improve the charge injection efficiency, and reduce the Tafel slope. Specifically, FeOOH plays a role in transporting photogenerated holes, while Co(OH)2 facilitates water oxidation reactions. In addition, the dual cocatalyst coating can slow down vanadium ion dissolution and improve PEC stability. This immersion method can easily be applied to large-area photoelectrodes.

Tailoring the Interfacial Composition of Heterostructure InP Quantum Dots for Efficient Electroluminescent Devices.

The formation of core-shell quantum dots (QDs) with type-I band alignment results in surface passivation, ensuring the efficient confinement of excitons for light-emitting applications. In such cases, the atomic composition at the core-shell heterojunction significantly affects the optical, and electrical properties of the QDs. However, for InP cores, shell materials are limited to compositions consisting of II-VI group elements. The restricted selection of shell materials leads to an interfacial misfit, resulting in a charge imbalance at the core-shell heterojunction. In this study, the effect of interfacial stoichiometry is investigated on the optical, and electrical properties of InP core-shell QDs. Direct Se injection strategy is employed during the synthesis of the InP core to regulate the interfacial chemical composition, resulting in the formation of an InZnSe alloy on the core surface. This InZnSe layer reduces the misfit between the InP core, and ZnSe shell, leading to a remarkable photoluminescence quantum yield of 95% with a narrow emission bandwidth of 34nm. The InZnSe interlayer significantly influences the electroluminescence (EL) processes, increasing the charge injection efficiency, and mitigating charge imbalance. A green-emitting EL device is demonstrated with a maximum luminance of 26370cd m-2, and a peak current efficiency of 31.5cd A-1.

SnS2 QDs@MXene Ohmic Junction-Based Surface Plasmon Coupling ECL Sensor to Detect Saliva Exosome for the Diagnosis of Childhood Asthma.

This study represents a novel surface plasmon coupling electrochemiluminescence (SPC-ECL) method for detecting salivary exosomes and the diagnosis of childhood asthma. First, SnS2 QDs@MXene Ohmic junctions was developed as efficient ECL emitters. The Ohmic junction provided a low resistance to reduce the contact resistance and improve charge injection efficiency, which enhanced the ECL signal by 2.76 times. Furthermore, the self-assembled surface plasmonic Bi@SiO2 array was prepared. When the ECL of SnS2 QDs@MXene resonated with the electronic oscillations in the Bi@SiO2 NPs array, the luminescence intensity was enhanced and regulated into the directionally polarized signal by the SPC-ECL effect. Remarkably, the detection of CD9-exosomes in saliva was achieved successfully based on the above sensing system, which can be used to analysis the acute exacerbation and chronic persistence of childhood asthma.

A ternary-structured NiCo-LDH/Ni/BiVO4 photoanode with enhanced charge dynamics for photoelectrochemical water splitting

Solar-driven photoelectrochemical (PEC) water splitting is one of the promising technologies to produce green hydrogen as the carbon-free energy carrier. However, the ideal photoanode material BiVO4 still suffers from sluggish carrier dynamic problem. Here, NiCo-LDH/Ni/BiVO4 (NC/N/BVO) composite photoanode with a three-layer structure was successfully fabricated by introducing Ni layer followed by NiCo-LDH on BiVO4 by magnetron sputtering and electrochemical deposition, respectively. The optimized structure of NC/N/BVO exhibited a photocurrent of 4.15 mA cm−2 (1.23 VREH) in neutral solution, which was 2.8 times of pristine BiVO4. Besides, the photocurrent can be well maintained at 98 % for NC/N/BVO in 1h reaction, which dramatically decreases to 60 % for BiVO4. In this composite photoanode, NiCo-LDH as excellent water oxidation catalyst can effectively enhance the kinetic process of water oxidation on the surface, while the introduction of Ni layer can not only promote the following deposition of NiCo-LDH being a finer nanostructure with high surface area, but also increase the charge conduction efficiency and promote the charge transfer process between NiCo-LDH and BiVO4 substrate. The appropriate deposition sequence of Ni and NiCo-LDH layers ultimately highly improved the charge injection efficiency of NC/N/BVO resulting in a high performance of PEC water splitting.

Giant Charge Separation-Driving Force Together with Ultrafluent Charge Transfer in TiO2/ZnFe-LDH Photoelectrode via Ferroelectric Interface Engineering.

Hydrogen fuel production using photoelectrochemical (PEC) water-splitting technology is incredibly noteworthy as it provides a sustainable and clean method to alleviate the energy environmental crisis. A highly rapid electron shuttle at the semiconductor/WOC (water oxidation cocatalyst) interface is vital to improve the bulk charge transfer and surface reaction kinetics of the photoelectrode in the PEC water-splitting system. Yet, the inevitably inferior interface transition tends to plague the performance enhancement on account of the collision of hole-electron transport across the semi/cat interface. Herein, we address these critical challenges via inserting ferroelectric layer BTO (BaTiO3) into the semi/cat interface. The embedded polarization electric field induced by ferroelectric BTO remarkably pumped hole transfer at the semiconductor/WOC (TiO2/ZnFe-LDH) interface and selectively tailored the electronic structure of LDH surface-active sites, leading to overwhelmingly improved surface hole transfer kinetics at LDH/electrolyte interface, which minish the electron-hole recombination in bulk and on the surface of TiO2. The TiO2 nanorods encapsulated by ferroelectric-assisted ZnFe-LDH achieve 105% charge separation efficiency improvement and 53.8% charge injection efficiency enhancement compared with pure TiO2. This finding offers a strategic design for electrocatalytic-assisted photoelectrode systems by ferroelectric-pumped charge extraction and transfer at the semiconductor/WOC interface.

Tailoring the Tunneling‐Effect‐Boosted Interfacial Charge Trapping via Effective Conjugation Length

AbstractHighly efficient charge injection and charge trapping stability of the tunneling layer are of desirable and practical importance to transistor memory applications. However, both of which can be contradictory to the nature properties of its material. It is herein demonstrated that lowering the energy mismatch of the tunneling layer by employing a longer conjugation length of the polymer can improve the charge injection efficiency, albeit the trapped charges will be easily diminished and finally losing its memory characteristics, and vice versa. To further elaborate and verify this concept, both materials are blended with distinct nature of properties as the tunneling layer in pentacene‐based transistor devices. As the results, the device using 300 nm SiO2 with optimum blending ratio displays a broad memory window of ≈77.6 V which is superior to the non‐blended tunneling layer carrying appropriate energy levels and band gap energy, not to mention, revealing fast operation time (≈1 s), low driving voltage (≈20 V), long retention (>104 s), and high switching stability over 50 cycles with on–off ratio of >104. Most importantly, this finding shed insight into the design of tunneling materials for advancing organic transistor memory technologies based on tunneling‐effect‐boosted interfacial charge trapping.

Boosting Photoelectrochemical Water Oxidation Performance of Ti–Fe2O3 Photoanode via NH2–MIL–53(FeCo) as a Cocatalyst

α–Fe2O3 is a promising photoanode that can be used for solar‐driven photoelectrochemical (PEC) water splitting. However, due to low carrier separation efficiency and slow water oxidation kinetics, the PEC performance of Ti–Fe2O3 is still severely hindered. Here, a novel inorganic–organic hybrid composite photoanode is prepared by depositing NH2–materials of institute Lavoisier (MIL)–53(FeCo) cocatalyst on the surface of Ti–Fe2O3 using solvothermal method. In the results, it is shown that the Ti–Fe2O3/NH2–MIL–53(FeCo) photoanode has a high photocurrent density (3.0 mA cm−2 at 1.23 V vs reversible hydrogen electrode (RHE), which is 5.1 times that of bare Ti–Fe2O3, and the initial potential of water oxidation also undergoes a negative change of about 100 mV. The separation efficiency of Ti–Fe2O3/NH2–MIL–53(FeCo) is significantly enhanced, and the charge injection efficiency increases from 17.6% to 68% at 1.23 V versus RHE. In the further research, it is suggested that the excellent PEC performance of Ti–Fe2O3/NH2–MIL–53(FeCo) may be attributed to an increase in carrier density, prolonged carrier recombination time, and an increase in exposed reactive sites. In this study, a new understanding for the design of Ti–Fe2O3 photoanodes with superior PEC performance based on metal organic framework modification is provided.

Based on thiophene-containing Zn(II) and Co(II) complexes: Synthesis, characterization, and application to dye-sensitized solar cells

Dye-sensitized solar Cells have attracted great attention recently due to their excellent advantages. This study introduces the cobalt and zinc metal complexes as a new class of sensitizers for evaluation. We report the synthesis and characterization of zinc and cobalt complexes of organic dyes and applications of Dye-Sensitive TiO2 Solar Cells. In this study, the reason we prefer cobalt and zinc complexes is that they provide a wide absorption spectrum and high molar absorption. The fact that these complexes have good energy level adaptations helps in efficient electron transfer. In the designed complexes, 4,5-diazafluoren metal complexes bonded with thiophene and carbonyl as electron donors and as electron-with drawing groups were synthesized. Structural characterization was achieved with FTIR, UV-Vis, and Maldi-MS. The metal complex binder dye has demonstrated promising DSSC properties such as short-circuit current, open-circuit voltage, and fill factor, indicating efficient charge generation and injection. The bathochromic shift seen in the UV-Vis spectra of the dyes was promising for good efficiency. Notably, the highest efficiency was obtained from ZnS2 with 0.61%, while the lowest was from CoS1 with 0.17%. The power conversion efficiencies (η) produced by CoS1, CoS2, ZnS1, and ZnS2 dyes exhibit device performance ZnS2 > ZnS1 > CoS2 > CoS1 respectively. With these results, the development of DSSCs is promising.

Molecular Probing Coupled with Density Functional Theory Calculation to Reveal the Influence of Fe Doping on Fe-NiOOH Electrode for High Current Density of Water Splitting.

Fe-doped NiOOH electrocatalysts have attracted wide interest for the exceptional oxygen evolution reaction (OER) performance, but the precise role of Fe doping on the improved intrinsic activity remains unclear. Herein, the molecular probe technique combined with density functional theory calculation is used to reveal the influence of the Fe atom on the rate-determining step of the OER reaction, where the pre-catalyst of hierarchical self-supporting NiFe layered double hydroxide [LDH] nanosheets equipped on nickel foam (NiFe LDH/NF) is generated via a facile and industrially well-matched one-pot corrosion method. The physical characterization results reveal the reconstruction of NiFe LDH into Fe-doped NiOOH for promoted OER, which has a lower OH* adsorption energy with fast subsequent steps that help in obtaining an improved charge injection efficiency compared to NiOOH. In addition, more exposed electroactive species and facile delivery of mass/electron inside the catalytic procedure actually have a high-quality contribution to the outstanding catalytic activity. Therefore, the NiFe LDH36/NF electrocatalyst provides high catalytic activities of 241 and 320mV at 10mA cm-2 toward the OER and overall water-splitting in 1m KOH. This work provides a promising avenue for the rational design of durable self-supporting electrodes toward large-scale water splitting.

Suppressed Thermal Quenching via Tetrafluoroborate-Induced Surface Reconstruction of CsPbBr3 Nanocrystals for Efficient Perovskite Light-Emitting Diodes.

Although metal-halide perovskite nanocrystals (NCs) have garnered significant attention for optoelectronic applications, the presence of electrically insulating organic ligands in CsPbBr3 NCs hinders efficient charge injection and transportation in light-emitting diodes (LEDs). A common approach to address this issue involves ligand exchange with shorter ligands and precise control of the surface ligand density through additional purification steps. Nevertheless, the practical application of these methods has been hindered by their poor structural integrity and high surface-defect density, which remain a challenge. Our investigation reveals that NOBF4 treatment effectively replaces native ligands with BF4- anions, in which BF4- anions are readily coordinated with the positively charged CsPbBr3 surface metal centers, thereby improving the photoluminescence quantum yield (PLQY) and thermal stability. In particular, the presence of BF4- anions coordinated at CsPbBr3 surfaces efficiently suppresses the pathway of excitons toward thermally activated nonradiative recombination, leading to minimal thermal quenching and superior device performance in green-emitting PeLEDs. Notably, PeLEDs based on CsPbBr3 NCs with the reconstructed surface via NOBF4 treatment exhibit an improved current efficiency of 31.12 cd/A and an external quantum efficiency of 11.24%, increased by 2.8 times compared to that of the pristine sample, indicating the enhanced hole-electron injection and transport into the CsPbBr3 NCs. Therefore, our results highlight the potential of NOBF4 as a versatile reagent for the ligand exchange and surface passivation of CsPbBr3 NCs, thereby offering promising prospects for the development of stable, high-performance PeLEDs.

In-situ construction of novel Sb2(S,Se)3/CdSe S-scheme heterojunction with enhanced photoelectrochemical performance

Abstract Antimony selenosulfide (Sb2(S,Se)3) was considered to have great potential for photoelectrochemical (PEC) water splitting applications due to its excellent chemical stability, good light absorption, abundant reserves and non-toxicity. However, Sb2(S,Se)3 faces some limitations in the field of PEC, such as the serious recombination problem of photogenerated carriers. Therefore effectively restraining its deep-level defects is the crucial for enhancing its photoelectrochemical properties. In this paper, We successfully fabricated Sb2(S,Se)3/CdSe S-scheme heterojunction via one-step hydrothermal method, which improves its solar absorption capacity, facilitates efficient carrier separation. And, Sb2(S,Se)3/CdSe S-scheme heterojunction can suppress the adverse effects of deep-level defects on the PEC performance of Sb2(S,Se)3. Under simulated solar irradiation, the light current density can reach 4.02 mA cm2 (33.5 times that of monomeric Sb2(S,Se)3) at 1.23 VRHE, accompanied by low initial voltage and extremely high surface charge injection efficiency. This study is of great significance for the application of Sb2(S,Se)3 in the PEC field.

Water-Based Recycling Process of FTO/SnO2 Substrate for Sustainable Perovskite Solar Cell Technology.

Fluorine-doped tin oxide (FTO) substrate is an important and expensive component in perovskite solar cells (PSCs), which accounts for up to 40% of a typical PSC raw material cost. In this study, we investigated the recyclability of SnO2/FTO in PSCs by washing the spent PSCs using different solvent such as dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetone, water, and acetone/water mixture. Characterisation of properties of the SnO2/FTO substrates recovered from the PSCshow the surface wettability of SnO2/FTO is largely unchanged with water washing while a higher hydrophobicity is obtained with organic solvent washing. Comparison of electronic properties of the SnO2/FTO substrate shows a downward shift of the conduction band by 180 meV with water washing, creating favourable energy alignment with adjacent perovskite for efficient interfacial charge injection. Consequently, PSCs using the water-based recycled SnO2/FTO substrates produced a high power conversion efficiency (PCE) of 19.33% which is comparable to the device using fresh SnO2/FTO substrate (PCE = 19.85%). Furthermore, we demonstrated that the water washing process could retain property of SnO2/FTO substrate for decent PSC performance up to four recycling cycles. This study opens new avenues towards recycling of valuable FTO substrates in PSCs for increased sustainability and cost-effectiveness.

Study on the interface electronic structure, strain modulation and transport properties of composite heterojunction of 2D semimetal TiS2 and MX2 (M=Mo, W, Cr, Zr, Hf; X=S, Se, Te) semiconductor

Ohmic contacts play a crucial role in realizing high-performance electronic devices based on two-dimensional materials. The contact between semimetals and semiconductors can mitigate the formation of metal-induced gap states (MIGS), thereby reducing the SBH, enhancing the efficiency of high charge injection, and facilitating the establishment of ohmic contacts. This study involves a systematic exploration of the contact characteristics between the two-dimensional semimetal TiS2 and semiconductor MX2 (M = Mo, W, Cr, Zr, Hf; X = S, Se, Te) through first-principles calculations. It is found that the TiS2/MoSe2 and TiS2/WSe2 heterojunction achieve ohmic contact. Investigations into their transport properties reveal that significant currents can be observed at relatively low voltages, indicating excellent transport performance of these heterojunctions. The TiS2/CrSe2 and TiS2/HfSe2 contact heterojunctions also show low Schottky barrier height (SBH), with the barrier height being adjustable under strain. The SBH of TiS2/CrSe2 and TiS2/HfSe2 heterojunctions are very close to zero under stresses of 4 % and −4%, respectively. This also implies that our research can offer valuable guidance for the development of adjustable Schottky nano-devices and high-performance optoelectronic devices.

Revisiting Sub-Band Gap Emission Mechanism in 2D Halide Perovskites: The Role of Defect States.

Understanding the sub-band gap luminescence in Ruddlesden-Popper 2D metal halide hybrid perovskites (2D HaPs) is essential for efficient charge injection and collection in optoelectronic devices. Still, its origins are still under debate with respect to the role of self-trapped excitons or radiative recombination via defect states. In this study, we characterized charge separation, recombination, and transport in single crystals, exfoliated layers, and polycrystalline thin films of butylammonium lead iodide (BA2PbI4), one of the most prominent 2D HaPs. We combined complementary defect- and exciton-sensitive methods such as photoluminescence (PL) spectroscopy, modulated and time-resolved surface photovoltage (SPV) spectroscopy, constant final state photoelectron yield spectroscopy (CFSYS), and constant light-induced magneto transport (CLIMAT), to demonstrate striking differences between charge separation induced by dissociation of excitons and by excitation of mobile charge carriers from defect states. Our results suggest that the broad sub-band gap emission in BA2PbI4 and other 2D HaPs is caused by radiative recombination via defect states (shallow as well as midgap states) rather than self-trapped excitons. Density functional theory (DFT) results show that common defects can readily occur and produce an energetic profile that agrees well with the experimental results. The DFT results suggest that the formation of iodine interstitials is the initial process leading to degradation, responsible for the emergence of midgap states, and that defect engineering will play a key role in enhancing the optoelectronic properties of 2D HaPs in the future.

Regulating coordinatively unsaturated Co active sites in TA@ZIF-L(Co) via tannic acid for efficient photoelectrochemical water oxidation

Metal-organic frameworks (MOFs) as a cocatalyst can enhance the photoelectrochemical (PEC) water oxidation performance to a certain extent, but still suffer from deficient exposure of active sites and low electron mobility. In this work, 2D Leaf-like zeolitic imidazolate frameworks (ZIF-L) were selected as a precursor for the generation of defective structures by tannic acid (TA) functionalization-assisted etching, and then coupling it with BiVO4 to prepare a novel and highly efficient TA@ZIF-L(Co)/BiVO4 photoanode by a simple impregnation method. The photocurrent density of TA@ZIF-L(Co)/BiVO4 composite photoanode achieves 4.21 mA cm−2 at 1.23 VRHE under AM 1.5 G illumination, which is superior to that of ZIF-L(Co)/BiVO4, and three times that of the bare BiVO4, with a charge injection efficiency of up to 80 %, and its stability is also remarkably improved. Experimental results and DFT calculations showed that the introduction of TA not only improved the light absorption efficiency, but also exposed more active sites, increased the electron density of the coordinatively unsaturated Co active sites, and enhanced the polarized electric field on the surface, thus accelerating electron mobility. This work demonstrates that TA as a surface modifier has great potential to activate metal sites and change the electronic environment of MOFs for BiVO4-based photoanode in PEC water oxidation, providing valuable insights into the rational design of photoanodes.

Cyanoacetamide co-sensitizers DY-1 and DY-2: Unveiling a promising path to highly efficient photovoltaic devices

This paper presents a novel approach for enhancing the efficiency of dye-sensitized solar cells (DSSCs) through the co-sensitization of cyanoacetamide-based dyes DY-1 and DY-2 with N3 dye. The synthesis and characterization of DY-1 and DY-2 co-sensitizers are described and their potential applications in photovoltaic devices are investigated. The absorption properties of DY-1 and DY-2 were analyzed, revealing their efficient light absorption in the visible range. The co-sensitization of DY-1-2 with N3 dye demonstrated a significant enhancement in photovoltaic efficiency, ranging from 7.40 % to 7.92 %. The reasons for this efficiency enhancement were thoroughly analyzed and attributed to several factors. First, the combination of DY-1-2 with the N3 dye led to a broader light absorption spectrum, enabling more efficient utilization of incident photons. Additionally, co-sensitization facilitates efficient charge separation and injection processes, contributing to improved photocurrent. The acid-base co-sensitization approach further enhances the overall efficiency by maximizing the charge transfer and coverage on the semiconductor surface. This study sheds light on the development of novel sensitizers to enhance the performance of DSSCs, and the findings contribute to the advancement of photovoltaic devices.

Janus MoSH/WSi2N4 van der Waals Heterostructure: Two-Dimensional Metal/Semiconductor Contact.

Constructing heterostructures from already synthesized two-dimensional materials is of significant importance. We performed a first-principles study to investigate the electronic properties and interfacial characteristics of Janus MoSH/WSi2N4 van der Waals heterostructure (vdWH) contacts. We demonstrate that the p-type Schottky formed by MoSH/WSi2N4 and MoHS/WSi2N4 has extremely low Schottky barrier heights (SBHs). Due to its excellent charge injection efficiency, Janus MoSH may be regarded as an effective metal contact for WSi2N4 semiconductors. Furthermore, the interfacial characteristics and electronic structure of Janus MoSH/WSi2N4 vdWHs can not only reduce/eliminate SBH, but also forms the transition from p-ShC to n-ShC type and from Schottky contact (ShC) to Ohmic contact (OhC) through the layer spacing and electric field. Our results can offer a fresh method for optoelectronic applications based on metal/semiconductor Janus MoSH/WSi2N4 vdW heterostructures, which have strong potential in optoelectronic applications.