Improved Charge Transfer Research Articles

Structural Decoration of Porphyrin/Phthalocyanine Photovoltaic Materials.

Porphyrin/phthalocyanine compounds with fascinating molecular structures have attracted widespread attention in the field of solar cells in recent years. In this review, we focus on the pivotal role of porphyrin and phthalocyanine compounds in enhancing the efficiency of solar cells. The review seamlessly integrates the intricate molecular structures of porphyrins and phthalocyanines with their proficiency in absorbing visible light and facilitating electron transfer, key processes in converting sunlight into electricity. By delving into the nuances of intramolecular regulation, aggregated states, and surface/interface structure manipulation, it elucidates how various levels of molecular modifications enhance solar cell efficiency through improved charge transfer, stability, and overall performance. This comprehensive exploration provides a detailed understanding of the complex relationship between molecular design and solar cell performance, discussing current advancements and potential future applications of these molecules in solar energy technology.

Improvement of SnFe2O4 OER electrochemical property by Sm doping for water splitting

Electrocatalysts are crucial for achieving highly efficient renewable energy conversion and storage applications. Nevertheless, doping proves to be a successful approach in creating affordable spinel oxides that exhibit exceptional electrochemical capabilities. Our study focuses on the preparation of a samarium (Sm)-doped SnFe2O4 catalyst to expand the activity and stability of the oxygen evolution reaction (OER). However, the Sm-doped SnFe2O4 catalyst shows a highly encouraging overpotential of 179 mV at a current density of 10 mA cm−2 and a reduced Tafel slope of 32 mA dec−1. It maintains its durability for a duration of 40 h and even after undergoing 5000th cycles. The Sm-doped SnFe2O4 catalyst exhibits several positive effects, including reduced overpotential, higher catalytic current density, improved charge transfer kinetics (Rct = 0.29 Ω), and increased ECSA (111.62 cm2) value. These improved superior activity of Sm-doped SnFe2O4 catalyst can be attributed to factors such as its unique interconnected structures morphology, strong synergistic effects of Sm with Sn and Fe and the robust OH− adsorption, which are more pronounced compared to the un-doped SnFe2O4, which greatly enhanced their performance in OER activity. These findings indicate that by incorporating rare earth (Sm) dopant with a high valence state, spinel oxide can be fine-tuned to potentially enhance OER optimization for energy-producing applications.

Exfoliation of Metal-Organic Frameworks to Give 2D MOF Nanosheets for the Electrocatalytic Oxygen Evolution Reaction.

The structure and properties of materials are determined by a diverse range of chemical bond formation and breaking mechanisms, which greatly motivates the development of selectively controlling the chemical bonds in order to achieve materials with specific characteristics. Here, an orientational intervening bond-breaking strategy is demonstrated for synthesizing ultrathin metal-organic framework (MOF) nanosheets through balancing the process of thermal decomposition and liquid nitrogen exfoliation. In such approach, proper thermal treatment can weaken the interlayer bond while maintaining the stability of the intralayer bond in the layered MOFs. And the following liquid nitrogen treatment results in significant deformation and stress in the layered MOFs' structure due to the instant temperature drop and drastic expansion of liquid N2, leading to the curling, detachment, and separation of the MOF layers. The produced MOF nanosheets with five cycles of treatment are primarily composed of nanosheets that are less than 10 nm in thickness. The MOF nanosheets exhibit enhanced catalytic performance in oxygen evolution reactions owing to the ultrathin thickness without capping agents which provide improved charge transfer efficiency and dense exposed active sites. This strategy underscores the significance of orientational intervention in chemical bonds to engineer innovative materials.

NH4Cl-assisted synthesis of TaON nanoparticle applied to photocatalytic hydrogen and oxygen evolution from water

Oxynitride semiconductors are promising photocatalyst materials for visible light-driven water splitting, while the synthesis of well crystalized oxynitride still remains challenge. In present work, narrow-bandgap TaON nanoparticles are synthesized via heating a vacuum-sealed mixture of KTaO3, Ta and NH4Cl. This method possesses multiple advantages in terms of lower calcination parameter, higher N conversion efficiency and superior photocatalytic activity in comparison with the traditional thermal ammonolysis using NH3 gas as a nitrogen source. Through the analysis of intermediates produced upon the elevation of heating temperature, a gas–solid-phase reaction between TaCl5 and Ta2O5 is demonstrated as the final step, which is conducive to decreasing thermal energy barrier and accelerating nitridation process. Precise control of preparation conditions, including calcination temperature and duration, allows for the regulation of surface O/N ratio of TaON particles to unity, resulting in optimized photocatalytic activity. Photoelectrochemical assessment and intensity modulated photocurrent spectroscopy provide convincing evidence for improved charge transfer efficiency of photoexcited holes at TaON surface. A Z-scheme overall water splitting is accomplished by employing the TaON as an effective oxygen evolution photocatalyst, SrTiO3:Rh as a hydrogen evolution photocatalyst, and reduced graphene oxide (rGO) as a solid-state electron mediator. This work presents a promising strategy for the synthesis of high-quality oxynitride materials in application to photocatalytic water splitting.

Exfoliation of Metal–Organic Frameworks to Give 2D MOF Nanosheets for the Electrocatalytic Oxygen Evolution Reaction

AbstractThe structure and properties of materials are determined by a diverse range of chemical bond formation and breaking mechanisms, which greatly motivates the development of selectively controlling the chemical bonds in order to achieve materials with specific characteristics. Here, an orientational intervening bond‐breaking strategy is demonstrated for synthesizing ultrathin metal–organic framework (MOF) nanosheets through balancing the process of thermal decomposition and liquid nitrogen exfoliation. In such approach, proper thermal treatment can weaken the interlayer bond while maintaining the stability of the intralayer bond in the layered MOFs. And the following liquid nitrogen treatment results in significant deformation and stress in the layered MOFs’ structure due to the instant temperature drop and drastic expansion of liquid N2, leading to the curling, detachment, and separation of the MOF layers. The produced MOF nanosheets with five cycles of treatment are primarily composed of nanosheets that are less than 10 nm in thickness. The MOF nanosheets exhibit enhanced catalytic performance in oxygen evolution reactions owing to the ultrathin thickness without capping agents which provide improved charge transfer efficiency and dense exposed active sites. This strategy underscores the significance of orientational intervention in chemical bonds to engineer innovative materials.

Solar-enhanced photodegradation of dye and drug mixture and evaluation of phytotoxicity on seed germination and growth by an eggshell HAp/Nb2O5 heterostructure

In this work, heterostructures of hydroxyapatite (HAp) and Nb2O5 (NO) were obtained to study their photocatalytic activity under sunlight. The samples were synthesized by the microwave-assisted hydrothermal method, and the calcium precursor used to obtain HAp was obtained from an eggshell. The influence of adding NO at 10, 30 and 50% by mass on the heterostructures was evaluated. The XRD results and the functional groups present in the FTIR spectrum confirmed the presence of the two phases in the heterostructures. UV–vis spectroscopy revealed that activation was promoted by sunlight, while PL and electrochemical analyses indicated minimized recombination of the electron/hole pairs of heterostructures due to improved charge transfer. The TEM micrographs indicated interfacial contact between the two materials. The photocatalytic efficiency of the materials was studied for the degradation of methylene blue (MB), crystal violet (CV) and tetracycline (TC) under sunlight irradiation. The heterostructure with 50% NO showed better efficiency than the other combinations and was also tested for degrading the mixture (MIX) of MB, CV and TC, for which the efficiencies were 100, 98.66 and 67.33%, respectively. Furthermore, the effects of the photocalytic dosage, concentration and pH of the solution were investigated through the MIX degradation efficiency. It was possible to propose the mechanism for the photocatalytic activity of the HAp/NO heterostructure as a direct Z-schema. The reusability of the photocatalyst and the germination tests with treated water indicated that the HAp/NO heterostructure has potential application as an efficient and nontoxic alternative for the degradation of contaminants.

Unveiling Electric Field Induced Ultrafast Charge Transfer Dynamics and Photoresponse Enhancement in Gold‐Interlayered Bi2Se3

AbstractIn the realm of optoelectronic applications, the incorporation of a metal interlayer between layers of a topological material holds significant potential. The interlayer introduces benefits such as improved charge transfer efficiency, tunable band alignment, plasmonics effect, and enhanced light‐matter interactions, paving the way for more efficient and versatile optoelectronic devices. This work explores the incorporation of gold between Bi2Se3, resulting in an enhancement in the response time of photoresponse of interlayered systems (Bi2Se3‐Au‐Bi2Se3). The introduction of a gold interlayer between Bi2Se3 significantly influences the overlayer structure, crystallinity, crystallite size, and even phonon behavior. Moreover, the responsivity of the interlayered device at a bias (2 V) is found to have high responsivity with fast response and decay time (τr = 0.1 ms, and τd = 24 ms of interlayered systems) as compared to intrinsic Bi2Se3(τr = 0.6 ms, and τd = 28 ms). This change is attributed to the bandgap alteration of the Bi2Se3/Au interface, which is monitored through transient spectroscopy performed at different electric biases. This study suggests that incorporating a gold interlayer holds potential benefits for various optoelectronic applications.

Investigating the impact of end-capped acceptor alterations to dimethyl fluorene-based hole transporting material for perovskite solar cells

Hole-transporting materials (HTMs) could boost the proficiency of third generation-perovskite solar cells since they have ultrafast charge mobility that improves optoelectronic and photovoltaic attributes. Five new H-shaped molecules were sketched using thiophene bridged, end-capped acceptor alteration on a dimethyl fluorene core-based molecule. Planarity measurements, absorption spectra, frontier molecular orbitals (FMOs), excitation energy (Ex), density of states (DOS), molecular electrostatic potentials (MEPs), transition density matrix (TDM), exciton binding energy, interaction coefficient, hole-electron overlap, open circuit voltage, fill factor, and power conversion efficiency were analyzed via DFT/MPW1P9W1/6-31G (d,p) for evaluating performance of perovskite solar cells. All newly sketched molecules with an A-π-D-π-A skeleton exhibited outstanding optoelectronic properties, including broader absorbance (563–740 nm) in chlorobenzene, indicating better solution processing. Lower band gaps (2.08–2.72 eV) than reference (3.78 eV) indicated efficient electron density transfer. Increased open-circuit voltage (1.55–2.02 eV) along with lower reorganization energies of the electron (0.043249–0.122527 eV) and hole (0.108105–0.148322 eV) lead to effective charge transport capabilities. Higher dipole moments indicated suitable film fabrication. A higher fill factor (0.9166–0.9325) and power conversion efficiency (34.31–45.49 %) led to an improved performance. Concisely, all the newly sketched molecules showed redshifted absorbance, narrower band gaps, deeper HOMO energies, improved charge transfer, higher softness, and smaller hardness values when compared to ZR, which confirms their superiority as future dopant-free HTM for PSCs.

CoS2/Ni3S4 − N − C heterostructured electrode materials derived from Prussian-blue analogs for supercapacitors

Prussian blue analogues (PBAs) have the advantages of dependable electrochemical performance and long service life when used as energy storage materials because of their face-centered cubic structure. In this case, the appropriate metal sulfide derivatives were created using NiCo prussian blue analogue nano units as a precursor, which took on the precursor's structural traits. More reaction sites are exposed by this distinctive structural design, and a little quantity of nitrogen-doped carbon is produced, which improves charge transfer. The box-like structure has a buffer effect on the stress of the active material during charging and discharging, and the heterostructure of mixed metal sulfides and nitrogen-doped carbon composite cubic can both significantly increase the electrode's electrochemical capacitance and cycling stability. The CoS2/Ni3S4–N–C offers a capacitance of 817C g−1 at 3 A g−1 and 556C g−1 at 20 A g−1. The CoS2/Ni3S4–N–C electrode also has outstanding cycle stability (98.2 % capacitance retention after 10,000 cycles). An asymmetric supercapacitor (ASC) device made of CoS2/Ni3S4–N–C with activated carbon electrodes exhibits exceptional cycle stability. With a retention rate of 103.7 % after 10,000 cycles at 10 A g−1 and an energy density of 40 Wh kg−1. Using density functional theory (DFT), the electron characteristics of Co2NiO4 and CoS2/Ni3S4–N–C are compared. CoS2/Ni3S4–N–C detected more state densities at the Fermi level, which causes more charge to accumulate. This shows that the heterojunction's electron conductivity is significantly greater than the oxide's, and ultimately leads to quicker reaction kinetics.

Enhanced Charge Transfer Process and Photocatalytic Activity over a Phosphonate-based MOF via Amorphization Strategy.

Recently, amorphous materials have gained great attention as an emerging kind of functional material, and their characteristics such as isotropy, absence of grain boundaries, and abundant defects are very likely to outrun the disadvantages of crystalline counterparts, such as low conductivity, and ultimately lead to improved charge transfer efficiency. Herein, we investigated the effect of amorphization on the charge transfer process and photocatalytic performance with a phosphonate-based metal-organic framework (FePPA) as the research object. Comprehensive experimental results suggest that compared to crystalline FePPA, amorphous FePPA has more distorted metal nodes, which affects the electron distribution and consequently improves the photogenerated charge separation efficiency. Meanwhile, the distorted metal nodes in amorphous FePPA also greatly promote the adsorption and activation of O2. Hence, amorphous FePPA exhibits a better performance of photocatalytic C(sp3)-H bond activation for selective oxidation of toluene to benzaldehyde. This work illustrates the advantages of amorphous MOFs in the charge transfer process, which is conducive to the further development of high performance MOFs-based photocatalysts.

Enhanced Charge Transfer Process and Photocatalytic Activity over a Phosphonate‐based MOF via Amorphization Strategy

AbstractRecently, amorphous materials have gained great attention as an emerging kind of functional material, and their characteristics such as isotropy, absence of grain boundaries, and abundant defects are very likely to outrun the disadvantages of crystalline counterparts, such as low conductivity, and ultimately lead to improved charge transfer efficiency. Herein, we investigated the effect of amorphization on the charge transfer process and photocatalytic performance with a phosphonate‐based metal–organic framework (FePPA) as the research object. Comprehensive experimental results suggest that compared to crystalline FePPA, amorphous FePPA has more distorted metal nodes, which affects the electron distribution and consequently improves the photogenerated charge separation efficiency. Meanwhile, the distorted metal nodes in amorphous FePPA also greatly promote the adsorption and activation of O2. Hence, amorphous FePPA exhibits a better performance of photocatalytic C(sp3)−H bond activation for selective oxidation of toluene to benzaldehyde. This work illustrates the advantages of amorphous MOFs in the charge transfer process, which is conducive to the further development of high performance MOFs‐based photocatalysts.

Ligand Mediated Assembly of CdS Colloids in 3D Porous Metal–Organic Framework Derived Scaffold with Multi‐Sites Heterojunctions for Efficient CO2 Photoreduction

AbstractThe inclusion of colloidal particles into 3D porous constructs to realize heterostructure ensembles enhances surface interactions and energy transfer that can transform the catalytic properties of conventional catalysts. However, assembling hydrophobic colloidal nanoparticles within hydrophilic 3D porous matrices to create tailored heterostructures and catalytic properties is particularly challenging. Here, a modified ligand grafting method is presented to spontaneously assemble CdS inorganic colloidal quantum dots within a metal‐organic framework (MOF) derived porous framework for efficient photocatalytic CO2 reduction. The grafted long chain molecular ligands effectively suppress phase separation and endow a molecular‐recognition effect to form ordered assembly microstructures. The proof‐of‐concept assembly of CdS and Prussian blue analogues (PBA) derived Co3O4 facilitates a high density of heterojunctions formation, improving charge transfer and extended lifetimes of photo‐induced electrons. Consequently, CdS/Co3O4 assembly exhibits exceptionally active and stable photocatalytic CO2 reduction activity, with a CO production rate of 73.9 µmol g−1 h−1 and CO selectivity of 98.9%. Importantly, the ligand grafting method can be generalized to achieve spontaneous assembly of quantum dots within various metal organic framework derived porous scaffolds. This work provides a rational strategy for precise self‐assembly of colloidal nanoparticles within porous microstructures, allowing tailored heterointerfaces for functional materials and applications.

Organic sandwich-structured carbon fiber/SiO2/PES electrochemical membrane with significantly improved charge transfer efficiency and water permeability

Electrochemical membrane separation has the potential for good degradation efficiency and mitigates membrane fouling. However, it is still a real challenge to further build stable organic substrate and improve its charge efficiency. In this study, an electric conductive and sandwich-structured carbon fiber/SiO2/polyether sulfone (CF/SiO2/PES) membrane showing good tetracycline (TC) removal at both acidic (pH = 3) and alkaline (pH = 9) conditions was fabricated by a facile phase conversion method. The CF/SiO2/PES membrane exhibited notably improved water permeability, augmented by 42 % higher with external voltage than that of the membrane without voltage assistance. Furthermore, the CF/SiO2/PES membrane performance in TC removal was systematically assessed under diverse conditions, encompassing TC concentration, pH values, and applied voltage. The membrane displayed a good removal efficiency of 93.6 % and 91.8 % for TC at acidic and alkaline conditions, respectively. Additionally, the degradation pathway of TC was proposed. Crucially, the CF/SiO2/PES membrane exhibited exceptional reusability and stability over eight consecutive runs. Mechanism study proved that the reactive species play a key role in the TC degradation during electro-filtration. The exceptional permeability, removal efficiency, and recyclability position the CF/SiO2/PES membrane as a promising solution for antibiotic wastewater treatment.

Regulating the Quantum Dots Integration to Improve the Performance of Tin–Lead Perovskite Solar Cells

AbstractDespite their advantageous attributes, such as a narrow bandgap and reduced toxicity, tin–lead halide perovskites (TLHPs) have received limited attention due to their lower power conversion efficiency (PCE) relative to lead‐only variants. In this study, a transformative approach is introduced that leverages perovskite quantum dots (PQDs) to optimize TLHP solar cells. While conventional oleyl‐capped PQDs enhance the open circuit voltage (VOC), the long‐chain ligands hinder charge transport. To overcome this limitation, a post‐treatment with isopropyl alcohol effectively dissociates these ligands and PQD crystals, resulting in reduced defect density, improved charge transfer, and elevated quasi‐Fermi level splitting in the TLHP device. Consequently, the PCE of the device is notably increased from 19.0% to 23.74% and elevated the VOC from 0.78 to 0.87 V, without compromising the photocurrent or fill factor. The findings highlight PQD modification as a compelling avenue for TLHP solar cell enhancement, particularly in boosting VOC.

Improved charge transfer on heterophase colloidal TiO2 with interaction between inserted atom and peroxysulfate for refractive antibiotics removal under visible light

Photocatalysis is a sustainable technique having unparalleled advantages in wastewater treatment. Its catalytic efficiency can be greatly enhanced by combining with Fenton-like reactions, e.g., persulfate activation-based oxidation. However, the performance of this coupled technique is mainly limited by the development of catalysts that connect two catalytic reaction systems. Herein, heterophase colloidal TiO2 with insertion of heteroatoms C and N was synthesized as a physicochemical stable visible light responsive photocatalyst enabling persulfate activation to selectively generate strong radicals of •OH and SO4•− for removal of refractory pollutants (i.e., florfenicol) via an enhanced electron-transfer route. The optoelectronic characterizations and DFT calculation reveal the changes of band structure, charge transfer and migration pathway after C, N elements inserted into heterophase crystal lattice. The N site favors both separation of photogenerated charge carriers and activation of persulfate, and the coupling mechanism is disclosed in detail. Meanwhile, the participation of the strong radicals in the florfenicol decomposition and the toxicity of intermediates are discussed. This work highlights the importance of non-transition metal oxide-based catalysts for synergistic photocatalysis and persulfate activation and provides a deep insight into the synergistic mechanisms in generating strong radicals at the molecular level.

Hyperbranched polyimide with triazole core structure for nonvolatile resistive switching memory

AbstractHyperbranched polyimides (HBPIs) possess a unique branched structure, which can make the lowest unoccupied molecular orbitals (LUMOs) degenerate and reduce the bandgap between the highest occupied molecular orbital (HOMO) and LUMO energy levels. The triazole group can facilitate the charge transfer process. Thus, a novel hyperbranched polyimide (HBPI‐TZA‐6FDA) has been prepared from new triazole derivative triamine monomer (TZA) and 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) for memory device. The memory device with the structure ITO/HBPI‐TZA‐6FDA/Al exhibits a low‐threshold voltage of −2.2 V and a high ON/OFF current ratio of about 105. Meanwhile, the memory device shows nonvolatile write once read many times (WORM) type memory behavior and excellent stability with an operation time of 104 at a continuous applied voltage of −1 V. Optical, electrochemical experiments, and molecular simulation have been carried out to illustrate the memory performance. The memory performance is governed by the charge transfer between TZA and 6FDA units. The branched structure and triazole unit can reduce the band gap between HOMO and LUMO energy levels effectively, which is favorable for improving charge transfer and reducing threshold voltage. The HBPI‐TZA‐6FDA‐based memory device is favorable for memory device applications due to its relatively low‐power consumption and high‐operation stability.

Self‐Floating Photocatalytic System for Highly Efficient Hydrogen Peroxide Production and Organic Synthesis on Carbon Dots Decorated Conjugated Microporous Polymer

AbstractPhotocatalytic oxygen (O2) reduction to hydrogen peroxide (H2O2) is considered to be a promising method for energy storage. However, it suffers from the rapid recombination of carriers, the limited solubility and slow diffusion of O2, and the self‐decomposition of H2O2 in traditional diphase systems. Here, a self‐floating carbon dots/conjugated microporous polymer (CDs/CMP) photocatalytic system is established for H2O2 production and organic synthesis. Due to the D–π–A structure, porous structure, and hydrophobicity, CMP induced the intramolecular charge transfer, exposed abundant reaction sites, and enhanced O2 adsorption. CDs act as “bridges” for electron transmission and regulate the surface hydrophobicity of CMP, further improving charge transfer and optimizing the reaction interface. CDs/CMP system exhibits a high H2O2 production of 8542.6 µmol g−1 h−1 and concurrent furoic acid production at 2.22 mm h−1. This H2O2 production rate is ≈90% higher than that in the diphase system, exceeding all previously reported photocatalysts in triphase systems. Notably, the CDs/CMP system achieves the relative separation of the photocatalysts and H2O2, suppressing the generated H2O2 self‐decomposition. Theoretical calculations and in situ characterizations reveal the mechanism of H2O2 and furoic acid evolution. This self‐floating system provides insights into exploring the application of metal‐free photocatalysts in heterogeneous reactions.

Highly Selective Tandem Photoelectrochemical C-H Activation via Bromine Evolution Reaction in Two-Phase Electrolyte.

The development of environmentally friendly and safe chemical processes using renewable energy sources is important. In this study, a photoelectrochemical (PEC) cell was used for the tandem bromination of sp3 carbon within a unique two-phase electrolyte system. By incorporation of a RuOx cocatalyst, the Ta3N5 photoelectrode demonstrated a remarkable selectivity for Br2 close to 100%. The kinetic study for charge carriers of photoelectrodes reveals that the improved charge transfer at Ta3N5/RuOx interfaces contributed to excellent photoelectrochemical Br2 evolution activity. The photoelectrochemically produced Br2 was utilized for bromination of α-sp3 carbon in toluene, 1-methylnaphthalene, ethylbenzene, or cyclohexane by the Ta3N5/RuOx photoanode with 100% regioselectivity. The coupling of the Ta3N5 photoanode and InP photocathode generated H2 and Br2 under light illumination without external bias. This study provides systematic insights into the design of photoelectrodes for solar-driven tandem bromination systems within the unique environment of a two-phase electrolyte system.

Construction of Nickel Molybdenum Sulfide/Black Phosphorous 3D Hierarchical Structure Toward High Performance Supercapacitor Electrodes.

Supercapacitors (SCs) with outstanding versatility have a lot of potential applications in next-generation electronics. However, their practical uses are limited by their short working potential window and ultralow-specific capacity. Herein, the facile one-step in-situ hydrothermal synthesis is employed for the construction of a NiMo3S4/BP (black phosphorous) hybrid with a 3D hierarchical structure. After optimization, the NiMo3S4/BP hybrid displays a high specific capacitance of 830 F/g at 1 A/g compared to the pristine NiMo3S4 electrode. The fabricated NiMo3S4/BP//NiCo2S4/Ti3C2Tx asymmetric supercapacitor exhibits a better specific capacitance of 120 F/g at 0.5 A/g, which also demonstrates a high energy density of 54 Wh/kg at 1148.53 W/kg and good cycle stability with capacity retention of 86% and 97% of Coulombic efficiency after 6000 cycles. Further from the DFT simulations, the hybrid NiMo3S4/BP structure shows higher conductivity and quantum capacitance, which demonstrate greater charge storage capability, due to enhanced electronic states near the Fermi level. The lower diffusion energy barrier for the electrolyte K+ ions in the hybrid structure is facilitated by improved charge transfer performance for the hybrid NiMo3S4/BP. This work highlights the potential significance of hybrid nanoarchitectonics and compositional tunability as an emerging method for improving the charge storage capabilities of active electrodes.

Improving charge transfer properties and solar cell performance by In-doped TiO2 as an efficient photoanode for dye-sensitized solar cells (DSSCs)

Dye-sensitized-solar cells (DSSCs) are of great interest as cost-effective and green energy producers. The vastly explored photoanodes are one of the most significant parts of DSSC and still play a crucial role. We employed the fast and facile sol-gel technique to synthesize and dope TiO2 mesoporous structure with indium atoms. Although In doping in the TiO2 structure has been used previously, there have been few research on its application as photoanode in DSSCs. We investigated TiO2:In as an appropriate candidate for photoanode in DSSC and evaluated its charge transfer and optical, structural, and electrochemical properties. Mott-Schottky results show that indium doping can increase the carrier concentration up to 1.1 × 1017 cm−3 and elevate the conductivity as well as charge transfer properties. The optical and structural properties were investigated by PL, Raman, and UV–visible methods, and the results showed that TiO2:In has suppressed recombination in its structure. Also, In-doping improves the electrochemical properties of the photoanodes. The EIS results establish that In corporation can reduce the charge transfer resistance to 33 Ω cm2. The champion TiO2:In-based DSSC shows an 8.62 % efficiency, which indicates a 55 % improvement compared to the non-doped TiO2.