Search Results (480)

Two-dimensional (2D) organic−inorganic hybrid perovskites (OIHPs) have emerged as promising candidates for next-generation optoelectronic applications. While vertical heterostructures of 2D OIHPs have been explored through mechanical stacking, the controlled fabrication of lateral heterostructures remains a significant challenge. Here, we present a lithography-free, van der Waals mask-assisted strategy for the deterministic fabrication of 2D OIHP lateral heterostructures. Mechanically exfoliated 2D materials such as graphene serve as removable masks that enable selective conversion of unmasked perovskite regions via ion exchange reaction. This technique enables the fabrication of various lateral heterostructures, such as BA₂MA₂Pb₃I₁₀/MAPbI₃, PEAPbI₄/MAPbI₃, as well as BA₂MAPb₂I₇/MAPbBr₃. Furthermore, complex multiheterostructures and superlattices can be constructed through sequential masking and conversion processes. Moreover, to investigate the electronic properties and demonstrate potential device applications of the lateral heterostructures, we have fabricated an electrical diode based on a BA₂MA₂Pb₃I₁₀/MAPbI₃ lateral heterostructure. Stable electrical rectifying behavior with a rectification ratio of around 10 was observed. This general and flexible approach provides a robust platform for constructing 2D OIHPs lateral heterostructures and opens new pathways for their integration into high-performance optoelectronic devices. Full article

The toxicity of lead in conventional perovskites and their inherent chemical instability impede the commercialization of perovskite-based optoelectronics. Therefore, it is vital to develop chemically stable and environmentally friendly Pb-free alternatives. Recently, zero-dimensional (0D) all-inorganic Cs₂ZnCl₄ doped with Sn(II) has emerged as a promising candidate, exhibiting superior chemical robustness, minimal biotoxicity, and exceptional optoelectronic properties. In this work, pressure effects on structure and optical properties in Sn(II)-doped all-inorganic zero-dimensional halide perovskite are investigated both experimentally and theoretically. The structure–property relationship of Sn(II)-doped Cs₂ZnCl₄ is studied using high-pressure techniques. Piezochromism, accompanied by a remarkable change in emission color from orange/red and green to orange/yellow, was obtained from 1 atm to 22.5 GPa. Angle dispersive synchrotron X-ray diffraction (ADXRD) patterns and Raman spectra manifest that the material underwent an isostructural phase transition followed by amorphization with increasing pressure. The piezochromism and band gap engineering originate from the pressure-induced lattice compression and isostructural phase transition. This work advances STE emission studies and provides a robust strategy to boost emission efficiency and to construct multifunctional materials with piezochromism in environmentally friendly perovskites, thus facilitating diverse future applications. Full article

Inorganic halide perovskites have garnered significant attention as promising candidates for photovoltaic and optoelectronic applications, owing to their enhanced thermal and chemical stability relative to hybrid perovskite materials. This review synthesizes recent progress in vapor-phase deposition methodologies, such as co-evaporation, close space sublimation (CSS), continuous flash sublimation (CFS), and chemical vapor deposition (CVD), which enable the precise modulation of film composition and morphology. Advances in material systems, including the stabilization of CsPbI₂Br, the introduction of tin-doped phases, and the investigation of lead-free double perovskites like Cs₂AgSbI₆ and Cs₂AgBiCl₆, are critically evaluated with respect to their impact on device performance. The incorporation of these materials into photovoltaic devices and tandem configurations is explored, with particular emphasis on improvements in power conversion efficiency and operational durability. Furthermore, interface engineering approaches tailored to vacuum-deposited films—such as defect passivation and energy-level alignment—are examined in detail. The potential for scalable manufacturing is assessed through simulation analyses, throughput modeling, and pilot-scale demonstrations, underscoring the feasibility of industrial-scale production. By offering a comprehensive overview of these advancements, this review provides valuable perspectives on the current landscape and prospective trajectories of vapor-deposited inorganic perovskite technologies. Full article

The one-dimensional (1D) Sb(III)-based organic–inorganic hybrid perovskite (AImd)₂¹_∞[SbI₅] (AImd = 1-allylimidazolium) crystallizes in the orthorhombic, centrosymmetric space group Pnma. The structure consists of corner-sharing [SbI₆] octahedra forming 1D chains separated by allylimidazolium cations. Void analysis through Mercury CSD software confirmed a densely packed lattice with a calculated void volume of 1.1%. Integrated quantum theory of atoms in molecules (QTAIM) and non-covalent interactions index (NCI) analyses showed that C–H···I interactions between the cations and the ¹_∞[SbI₅]²⁻ network predominantly stabilize the supramolecular assembly followed by N–H···I hydrogen bonds. The calculated growth morphology (GM) model fits very well to the experimental morphology. UV–Vis diffuse reflectance spectroscopy allowed us to determine the optical band gap to 3.15 eV. Density functional theory (DFT) calculations employing the B3LYP, CAM-B3LYP, and PBE0 functionals were benchmarked against experimental data. CAM-B3LYP best reproduced Sb–I bond lengths, while PBE0 more accurately captured the HOMO–LUMO gap and the associated electronic descriptors. These results support the assignment of an inorganic-to-organic [Sb–I] → π* charge-transfer excitation, and clarify how structural dimensionality and cation identity shape the material’s optoelectronic properties. Full article

Two-dimensional (2D) hybrid organic–inorganic perovskites (HOIPs) have attracted considerable attention in optoelectronic applications, owing to their remarkable characteristics. Nevertheless, the application of 2D HOIPs encounters inherent challenges due to the presence of insulating organic spacers, which create barriers for efficient interlayer charge transport (CT). To tackle this issue, we propose a BA₂MAPb₂I₇/PEA₂MA₂Pb₃I₁₀ bilayer heterostructure, where efficient interlayer energy transfer (ET) facilitates compensation for the restricted charge transport across the organic spacer. Our findings reveal that under 532 nm light illumination, the BA₂MAPb₂I₇/PEA₂MA₂Pb₃I₁₀ heterostructure photodetector exhibits a significant photocurrent enhancement compared with that of the pure PEA₂MA₂Pb₃I₁₀ device, mainly due to the contribution of the ET process. In contrast, under 600 nm light illumination, where ET is absent, the enhancement is rather limited, emphasizing the critical role of ET in boosting device performance. The overlap of the PL emission peak of BA₂MAPb₂I₇ with the absorption spectra of PEA₂MA₂Pb₃I₁₀, alongside the PL quenching of BA₂MAPb₂I₇ and the enhanced emission of PEA₂MA₂Pb₃I₁₀ provide confirmation of the existence of ET in the BA₂MAPb₂I₇/PEA₂MA₂Pb₃I₁₀ heterostructure. Furthermore, the PL enhancement factor followed a 1/d² relationship with the thickness of the hBN layer, indicating that ET originates from 2D-to-2D dipole–dipole coupling. This study not only highlights the potential of leveraging ET mechanisms to overcome the limitations of interlayer CT, but also contributes to the fundamental understanding required for engineering advanced 2D HOIP optoelectronic systems. Full article

Gel-polymer electrolytes offer a promising route toward safer and more stable sodium-ion batteries, but conventional polymer systems often suffer from low ionic conductivity and limited voltage stability. In this study, we developed composite GPEs by embedding methylammonium lead chloride (CH₃NH₃PbCl₃, MPCl) into a UV-crosslinked ethoxylated trimethylolpropane triacrylate (ETPTA) matrix, with sodium alginate (SA) as an ionic conduction enhancer. Three types of membranes—GPE-P, GPE-El, and GPE-Eh—were synthesized and systematically compared. Among them, the high-MPCl formulation (GPE-Eh) exhibited the best performance, achieving a high ionic conductivity of 2.14 × 10⁻³ S·cm⁻¹, a sodium-ion transference number of 0.66, and a wide electrochemical window of approximately 4.9 V vs. Na⁺/Na. In symmetric Na|GPE|Na cells, GPE-Eh enabled stable sodium plating/stripping for over 600 h with low polarization. In Na|GPE|NVP cells, it delivered a high capacity retention of ~79% after 500 cycles and recovered ~89% of its initial capacity after high-rate cycling. These findings demonstrate that the perovskite–polymer composite structure significantly improves ion transport, interfacial stability, and electrochemical durability, offering a viable path for the development of next-generation quasi-solid-state sodium-ion batteries. Full article

In this study, we investigate the influence of the halogen elements bromine (Br) and chlorine (Cl) on iodine defect properties primarily in FAPbI₃ through first-principles calculations, aiming to understand the effect of high defect densities on the efficiency of organic–inorganic hybrid perovskite cells. The results indicate that Br and Cl interstitials minimally alter the overall band structure of FAPbI₃ but significantly modify the defect energy levels. Br and Cl interstitials, with defect states closer to the valence band and lower formation energies, effectively convert deep-level traps induced by iodine interstitials (I_i) into shallow-level traps. This conversion enhances carrier transport by reducing non-radiative recombination while preserving light absorption efficiency. Excess Br/Cl co-doping in FAPbI₃ synthesis thereby suppresses non-radiative recombination and mitigates the detrimental effects of iodide-related defects. Full article

Barium stannate (BaSnO₃) has emerged as a promising alternative electron transport material owing to its superior electron mobility, resistance to UV degradation, and energy bandgap tunability, yet BaSnO₃-based perovskite solar cells have not reached the efficiency levels of TiO₂-based designs. This theoretical study presents a design-driven evaluation of BaSnO₃-based perovskite solar cell architectures, incorporating MAPbI₃ or FAMAPbI₃ perovskite materials, Spiro-OMeTAD, or Cu₂O hole transport materials as well as hole-free configurations, under varying light intensity. Using a systematic device modelling approach, we explore the influence of key design variables—such as layer thickness, donor density, and interface defect concentration—of BaSnO₃ and operating temperature on the power conversion efficiency (PCE). Among the proposed designs, the FTO/BaSnO₃/FAMAPbI₃/Cu₂O/Au heterostructure exhibits an exceptionally effective arrangement with PCE of 38.2% under concentrated light (10,000 W/m², or 10 Sun). The structure also demonstrates strong thermal robustness up to 400 K, with a low temperature coefficient of −0.078% K⁻¹. These results underscore the importance of material and structural optimisation in PSC design and highlight the role of high-mobility, thermally stable inorganic transport layers—BaSnO₃ as the electron transport material (ETM) and Cu₂O as the hole transport material (HTM)—in enabling efficient and stable photovoltaic performance under high irradiance. The study contributes valuable insights into the rational design of high-performance PSCs for emerging solar technologies. Full article

Artificial photoelectric synapses exhibit great potential for overcoming the Von Neumann bottleneck in computational systems. All-inorganic halide perovskites hold considerable promise in photoelectric synapses due to their superior photon-harvesting efficiency. In this study, a novel wavy-structured CsPbBr₃/ZnO hybrid film was realized by depositing zinc oxide (ZnO) onto island-like CsPbBr₃ film via atomic layer deposition (ALD) at 70 °C. Due to the capability of ALD to grow high-quality films over small surface areas, dense and thin ZnO film filled the gaps between the island-shaped CsPbBr₃ grains, thereby enabling reduced light-absorption losses and efficient charge transport between the CsPbBr₃ light absorber and the ZnO electron-transport layer. This ZnO/island-like CsPbBr₃ hybrid synaptic transistor could operate at a drain-source voltage of 1.0 V and a gate-source voltage of 0 V triggered by green light (500 nm) pulses with low light intensities of 0.035 mW/cm². The device exhibited a quiescent current of ~0.5 nA. Notably, after patterning, it achieved a significantly reduced off-state current of 10⁻¹¹ A and decreased the quiescent current to 0.02 nA. In addition, this transistor was able to mimic fundamental synaptic behaviors, including excitatory postsynaptic currents (EPSCs), paired-pulse facilitation (PPF), short-term to long-term plasticity (STP to LTP) transitions, and learning-experience behaviors. This straightforward strategy demonstrates the possibility of utilizing neuromorphic synaptic device applications under low voltage and weak light conditions. Full article

Perovskite quantum dots (PVK QDs) are gaining significant attention as potential materials for next-generation memory devices leveraged by their ion dynamics, quantum confinement, optoelectronic synergy, bandgap tunability, and solution-processable fabrication. In this review paper, we explore the fundamental characteristics of organic/inorganic halide PVK QDs and their role in resistive switching memory architectures. We provide an overview of halide PVK QDs synthesis techniques, switching mechanisms, and recent advancements in memristive applications. Special emphasis is placed on the ionic migration and charge trapping phenomena governing resistive switching, along with the prospects of photonic memory devices that leverage the intrinsic photosensitivity of PVK QDs. Despite their advantages, challenges such as stability, scalability, and environmental concerns remain critical hurdles. We conclude this review with insights into potential strategies for enhancing the reliability and commercial viability of PVK QD-based memory technologies. Full article

Organic–inorganic hybrid halide perovskites have emerged as promising optoelectronic materials owing to their exceptional optoelectronic properties and versatile crystal structures. The introduction of chiral organic ligands into perovskite frameworks, breaking the inversion symmetry of the structure, has attracted significant attention toward chiral perovskites. Herein, the recent advances in various synthesis strategies for chiral perovskite single crystals (SCs) are systematically demonstrated. Then, we elucidate an in-depth understanding of the chirality transfer mechanisms from chiral organic ligands to perovskite inorganic frameworks. Furthermore, representative examples of chiral perovskite SC-based applications are comprehensively discussed, including circularly polarized light (CPL) photodetection, nonlinear optical (NLO) responses, and other emerging chirality-dependent applications. In the end, an outlook for future challenges and research opportunities is provided, highlighting the transformative potential of chiral perovskites in next-generation optoelectronic devices. Full article

Organic–inorganic hybrid flexible perovskite solar cells (F-PSCs) have garnered considerable interest owing to their exceptional power conversion efficiency (PCE) and stable operational characteristics. However, F-PSCs continue to exhibit significantly lower PCE than their rigid counterparts. Herein, we employed 3-chloro-4-methoxybenzylamine hydrochloride (CMBACl) treatment to grow in situ two-dimensional (2D) perovskite layers on three-dimensional (3D) perovskite films. Through comprehensive physicochemical characterization, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) mapping, we demonstrated that CMBACl treatment enabled the in situ growth of two-dimensional (2D) perovskite layers on three-dimensional (3D) perovskite films via chemical interactions between CMBA⁺ cations and undercoordinated Pb²⁺ sites. The organic cation (CMBA⁺) bound to uncoordinated Pb²⁺ ions and residual PbI₂, while the chlorine anion (Cl⁻) filled iodine vacancies in the perovskite lattice, thereby forming a high-quality 2D/3D heterojunction structure. The CMBACl treatment effectively passivated surface defects in the perovskite films, prolonged charge carrier lifetimes, and enhanced the operational stability of the photovoltaic devices. Additionally, the hybrid 2D/3D architecture also improved energy band matching, thereby boosting charge transfer performance. The optimized flexible devices demonstrated a PCE of 23.15%, while retaining over 82% of their initial efficiency after enduring 5000 bending cycles under a 5 mm curvature radius (R = 5 mm). The unpackaged devices retained 94% of their initial efficiency after 1000 h under ambient conditions with a relative humidity (RH) of 45 ± 5%. This strategy offers practical guidelines for selecting interface passivation materials to enhance the efficiency and stability of F-PSCs. Full article

Single-phase white-light-emitting materials, particularly 2D hybrid organic–inorganic halide perovskites, have garnered significant attention due to their strong electron–phonon interactions, which lead to broad luminescence and a notable Stokes shift resulting from self-trapped exciton recombination. However, 2D lead iodide perovskites typically display these characteristics poorly, restricting their efficiency as white-light emitters. This study presents a 2D lead iodide perovskite that incorporates a fluorinated π-conjugated aggregation-induced enhanced emission luminophore, FPCSA, as a bulky organic cation to create a quasi-2D perovskite. The FPCSA cation establishes a Type II energy level alignment with the lead iodide layer in the 2D perovskite, and a significant energy offset effectively suppresses charge transfer, enabling independent emission from both the organic and inorganic layers while facilitating self-trapped exciton formation. Under 315 nm UV excitation, this material demonstrates warm white-light emission with RGB triple-band photoluminescence stemming from the electronically decoupled FPCSA and perovskite layers. These findings provide a promising new method for designing efficient single-phase white-light-emitting materials for optoelectronic applications. Full article

This study aims to enhance optoelectronic properties of all-inorganic perovskite photodetectors (PDs) by incorporating a bilayer electron transport layer (ETL). The bilayer ETL composed of SnO₂ and ZnO effectively optimizes energy level alignment at the interface, facilitating efficient electron extraction from the CsPbI₂Br perovskite layer while suppressing shunt pathways. Additionally, it enhances interfacial properties by mitigating defects and minimizing dark current leakage, thereby improving overall device performance. As a result, the bilayer ETL-based PDs exhibit broadband photoresponsivity in 300 to 700 nm with a responsivity of 0.45 A W⁻¹ and a specific detectivity of 9 × 10¹³ Jones, outperforming the single-ETL devices. Additionally, they demonstrate stable cyclic photoresponsivity with fast response times (14 μs for turn-on and 32 μs for turn-off). The bilayer ETL also improves long-term reliability and thermal stability, highlighting its potential for high performance, reliability, and practical applications of all-inorganic perovskite PDs. Full article

The increasing spread of infectious diseases caused by pathogenic microorganisms underscores the urgent need for highly sensitive, portable, and rapid nucleic acid detection technologies to facilitate early diagnosis and effective prevention. In this study, we developed a fluorescence-based nucleic acid detection platform that integrates a microfluidic chip with an all-inorganic perovskite photodetector. The system enables integrated operation of nucleic acid extraction, purification, and amplification on a microfluidic chip, combined with real-time electrical signal readout via a CsPbBr₃ perovskite photodetector. Experimental results indicate that the photodetector exhibits high responsivity at 530 nm, aligning well with the primary emission peak of FAM. The system demonstrates a strong linear correlation between photocurrent and FAM concentration over the range of 0.01–0.4 μM (R² = 0.928), with a low detection limit of 0.01 μM and excellent reproducibility across multiple measurements. Validation using FAM standard solutions and Escherichia coli samples confirmed the system’s reliable linearity and signal stability. This platform demonstrates strong potential for rapid pathogen screening and point-of-care diagnostic applications. Full article