New Advanced Hybrid Organic–Inorganic Complex

Semiconductors - New hybrid organic–inorganic complexes of perylene with nanodiamonds were developed and fabricated. The fact of complex formation was confirmed by the analysis of the...     

Spontaneous Hybrid Nano-Domain Behavior of the Organic–Inorganic Hybrid Perovskites

In hybrid perovskites, the organic molecules and inorganic frameworks exhibit distinct static and dynamic characteristics. Their coupling will lead to fascinating phenomena, such as large polarons, dynamic Rashba–Dresselhaus effects, etc. In this paper, deep potential molecular dynamics (DPMD) is employed, a large-scale MD simulation scheme with DFT accuracy, to study hybrid perovskites formamidinium lead iodide (FAPbI₃) and methylamonium lead iodide (MAPbI₃). A spontaneous hybrid nano-domain behavior, namely multiple molecular rotation nano-domains embedded into a single [PbI₆]⁴⁻ octahedra rotation domain, is first discovered at low temperatures. The behavior originates from the interplay between the long range order of molecular rotation and local lattice deformation, and clarifies the puzzling structural features of FAPbI₃ at low temperatures. The work provides new insights into the structural characteristics and stability of hybrid perovskite, as well as new ideas for the structural characterization of organic–inorganic coupled systems.     

Transparent and Reusable Nanostencil Lithography for Organic–Inorganic Hybrid Perovskite Nanodevices

Organic—inorganic hybrid perovskites have attracted considerable attention for developing novel optoelectronic devices owing to their excellent photoresponses. However, conventional nanolithography of hybrid perovskites remains a challenge because they undergo severe damage in standard lithographic solvents, which prohibits device miniaturization and integration. In this study, a novel transparent stencil nanolithography (t-SL) technique is developed based on focused ion beam (FIB)-assisted polyethylene terephthalate (PET) direct patterning. The proposed t-SL enables ultrahigh lithography resolution down to 100 nm and accurate stencil mask alignment. Moreover, the stencil mask can be reused more than ten times, which is cost-effective for device fabrication. By applying this lithographic technique to hybrid perovskites, a high-performance 2D hybrid perovskite heterostructure photodetector is fabricated. The responsivity and detectivity of the proposed heterostructure photodetector can reach up to 28.3 A W⁻¹ and 1.5 × 10¹³ Jones, respectively. This t-SL nanolithography technique based on FIB-assisted PET direct patterning can effectively support the miniaturization and integration of hybrid-perovskite-based electronic devices.     

Hybrid Organic–Inorganic Halide Post-Perovskite 3-Cyanopyridinium Lead Tribromide for Optoelectronic Applications

2D halide perovskite-like semiconductors are attractive materials for various optoelectronic applications, from photovoltaics to lasing. To date, the most studied families of such low-dimensional halide perovskite-like compounds are Ruddlesden–Popper, Dion–Jacobson, and other phases that can be derived from 3D halide perovskites by slicing along different crystallographic directions, which leads to the spatially isotropic corner-sharing connectivity type of metal-halide octahedra in the 2D layer plane. In this work, a new family of hybrid organic–inorganic 2D lead halides is introduced, by reporting the first example of the hybrid organic–inorganic post-perovskite 3-cyanopyridinium lead tribromide (3cp)PbBr₃. The post-perovskite structure has unique octahedra connectivity type in the layer plane: a typical “perovskite-like” corner-sharing connectivity pattern in one direction, and the rare edge-sharing connectivity pattern in the other. Such connectivity leads to significant anisotropy in the material properties within the inorganic layer plane. Moreover, the dense organic cation packing results in the formation of 1D fully organic bands in the electronic structure, offering the prospects of the involvement of the organic subsystem into material's optoelectronic properties. The (3cp)PbBr₃ clearly shows the 2D quantum size effect with a bandgap around 3.2 eV and typical broadband self-trapped excitonic photoluminescence at temperatures below 200 K.     

Crystallization of 2D Hybrid Organic–Inorganic Perovskites Templated by Conductive Substrates

2D hybrid organic–inorganic perovskites are valued in optoelectronic applications for their tunable bandgap and excellent moisture and irradiation stability. These properties stem from both the chemical composition and crystallinity of the layer formed. Defects in the lattice, impurities, and crystal grain boundaries generally introduce trap states and surface energy pinning, limiting the ultimate performance of the perovskite; hence, an in-depth understanding of the crystallization process is indispensable. Here, a kinetic and thermodynamic study of 2D perovskite layer crystallization on transparent conductive substrates are provided—fluorine-doped tin oxide and graphene. Due to markedly different surface structure and chemistry, the two substrates interact differently with the perovskite layer. A time-resolved grazing-incidence wide-angle X-ray scattering (GIWAXS) is used to monitor the crystallization on the two substrates. Molecular dynamics simulations are employed to explain the experimental data and to rationalize the perovskite layer formation. The findings assist substrate selection based on the required film morphology, revealing the structural dynamics during the crystallization process, thus helping to tackle the technological challenges of structure formation of 2D perovskites for optoelectronic devices.     

Flexible and Air-Stable Near-Infrared Sensors Based on Solution-Processed Inorganic–Organic Hybrid Phototransistors

Flexible and air-stable phototransistors are highly demanded for wearable near-infrared (NIR) image sensors. However, advanced NIR sensors via low-cost, solution-based processes remained a challenge. Herein, high-performance inorganic–organic hybrid phototransistors are achieved based on solution processed n-type metal oxide/polymer semiconductor heterostructures of In₂O₃/poly{5,5′-bis[3,5-bis(thienyl)phenyl]-2,2′-bithiophene-3-ethylesterthiophene]} (PTPBT-ET). The In₂O₃/PTPBT-ET hybrid phototransistor combines the advantages of both fast electron transport in In₂O₃ and high photoresponse in PTPBT-ET, showing high saturation mobility of 7.1 cm² V⁻¹ s⁻¹ and large current on/off ratio of >10⁷. As a result, the phototransistor exhibits high performance towards NIR light sensing with a responsivity of 200 A W⁻¹, a specific detectivity of 1.2 × 10¹³ Jones, and fast photoresponse with rise/fall time of 5/120 ms. Remarkably, the hybrid phototransistor, without any passivation, demonstrates excellent electrical stability without performance degradation even after 160 days in air. A 10 × 10 phototransistor array is also enabled by virtue of the high device uniformity. Lastly, flexible In₂O₃/PTPBT-ET phototransistor on polyimide substrate is attained, exhibiting outstanding mechanical flexibility up to 1000 bending/releasing cycles at a bending radius of 5 mm. These achievements pave the way for constructing air-stable hybrid phototransistors for flexible NIR image sensor applications.     

Self-Polarized Organic–Inorganic Hybrid Ferroelectric Cathode Coatings Assisted High Performance All-Solid-State Lithium Battery

Ferroelectrics can significantly boost electrochemical performances of all-solid-state batteries by constructing built-in electric field to reduce the space charge layer at cathode/solid-state electrolyte interface. However, the construction mechanism of ferroelectric built-in electric field is poorly understood. Herein, the guanidinium perchlorate (GClO₄) ferroelectrics as the cathode coatings in the LiCoO₂-based all-solid-state lithium battery are reported, which has state-of-the-art specific capacity of 210.6 mAh g⁻¹ (91.6% of the liquid battery). Systematic studies reveal that the flexoelectric effect originating from the lattice mismatch between GClO₄ and LiCoO₂ gives GClO₄ coatings the single-domain state and upward self-polarization. Consequently, a vertically downward built-in electric field is generated relative to the cathode, which transports the lithium ions inside the electrolyte to the three-phase interface to alleviate the space charge layer. These findings highlight that the microstructural characteristics of ferroelectric and electrode materials are the primary concern for building an effective built-in electric field.     

Versatile Solution-Processed Organic–Inorganic Hybrid Superlattices for Ultraflexible and Transparent High-Performance Optoelectronic Devices

Crystalline or amorphous metal oxides are widely used in various optoelectronic devices as key components, such as transparent conductive electrodes, dielectrics or semiconducting active layers for thin-film transistor (TFT) backplanes in large-area displays, photovoltaics, and light-emitting diodes. Although crystalline inorganic materials demonstrate outstanding optoelectronic performance, owing to their wide bandgaps, large conductivities, and high carrier mobilities, their inherent brittleness makes them vulnerable to mechanical stress, thereby limiting the use of metal-oxide films in emerging flexible electronic applications. In this study, stress-diffusive organic–inorganic hybrid superlattice nanostructures are developed to overcome the mechanical limitation of crystalline oxides and to provide high mechanical stability to metal-oxide semiconductors. In particular, hybrid transparent superlattice electrodes based on crystalline indium–tin oxide exhibit high electrical conductivities of up to 555 S cm^–1 (resistance variation < 3%) and effectively reduce the mechanical stress on the inorganic layer (up to 10 000 bending cycles with a radius of 1 mm). Furthermore, to ensure the viability of the hybrid superlattice flexible electronics, all solution-processed superlattice crystalline indium–gallium-oxide TFTs are implemented on a thin (≈5 µm) polyimide substrate, providing highly robust and excellent electrical performance (average mobility of 7.6 cm² V^–1 s^–1).     

Inorganic–Organic Hybrid Dielectrics for Energy Conversion: Mechanism,Strategy, and Applications

Dielectric materials with higher energy storage and electromagnetic (EM) energy conversion are in high demand to advance electronic devices, military stealth, and mitigate EM wave pollution. Existing dielectric materials for high-energy-storage electronics and dielectric loss electromagnetic wave absorbers are studied toward realizing these goals, each aligned with the current global grand challenges. Libraries of dielectric materials with desirable permittivity, dielectric loss, and/or dielectric breakdown strength potentially meeting the device requirements are reviewed here. Regardless, aimed at translating these into energy storage devices, the oft-encountered shortcomings can be caused by either of two confluences: a) low permittivity, high dielectric loss, and low breakdown strength; b) low permittivity, low dielectric loss, and process complexity. Contextualizing these aspects and the overarching objectives of enabling high-efficiency energy storage and EM energy conversion, recent advances in by-design inorganic–organic hybrid materials are reviewed here, with a focus on design approaches, preparation methods, and characterization techniques. In light of their strengths and weaknesses, potential strategies to foster their commercial adoption are critically interrogated.     

Inorganic–Organic Nanocomposites Based on Aggregation-Induced Emission Luminogens

The emergence of aggregation-induced emission (AIE) has significantly facilitated the development of various fields including chemical sensing, bioimaging, theranostics, and photoelectric devices. Aiming to constructing high-performance versatile materials, integrating AIE luminogens with functionalized supporting agents is an intriguing strategy. Inorganic nanomaterials have attracted significant scientific interest in functionalizing AIE luminogens via combining the advantages of them both. In addition to these intrinsic features of specific inorganic materials, including high stability, superior biocompatibility, and facile modification, the stubborn spatial confinement effect of inorganic structure provides AIE moieties with favorable aggregated conditions. Representative work and some very first attempts of constructing AIE luminogens-based inorganic–organic nanocomposites are presented in this review. The sections are organized according to the dimension of inorganic nanomaterials and focused on their construction, mechanism, and application.     

Synthesis of 0D Manganese-Based Organic–Inorganic Hybrid Perovskite and Its Application in Lead-Free Red Light-Emitting Diode

Lead-based perovskite light-emitting diodes (PeLEDs) have exhibited excellent purity, high efficiency, and good brightness. In order to develop nontoxic, highly luminescent metal halide perovskite materials, tin, copper, germanium, zinc, bismuth, and other lead-free perovskites have been developed. Here, a novel 0D manganese-based (Mn-based) organic–inorganic hybrid perovskite with the red emission located at 629 nm, high photoluminescence quantum yield of 80%, and millisecond level triplet lifetime is reported. When applied as the emissive layer in the PeLEDs, the maximum recording brightness of devices after optimization is 4700 cd m⁻², and the peak external quantum efficiency is 9.8%. The half-life of the device reaches 5.5 h at 5 V. The performance and stability of Mn-based PeLEDs are one order of magnitude higher than those of other lead-free PeLEDs. This work clearly shows that the Mn-based perovskite will provide another route to fabricate stable and high-performance lead-free PeLEDs.     

Electrical Properties of Organic–Inorganic Semiconductor Device Based on Rhodamine-101

Rhodamine-101 (Rh101) thin films on n-type Si substrates have been formed by means of evaporation, thus Sn/Rh101/n-Si heterojunctions have been fabricated. The Sn/Rh101/n-Si devices are rectifying. The optical energy gaps have been determined from the absorption spectra in the wavelength range of 400 nm to 700 nm. Rh101 has been characterized by direct optical absorption with an optical edge at 2.05 ± 0.05 eV and by indirect optical absorption with␣an optical edge at 1.80 ± 0.05 eV. It was demonstrated that trap-charge-limited current is the dominant transport mechanism at large forward bias. A␣mobility value of μ = 7.31 × 10⁻⁶ cm² V⁻¹ s⁻¹ for Rh101 has been obtained from the forward-bias current–voltage characteristics.     

Printable Ultra-Flexible Fluorinated Organic–Inorganic Nanohybrid Sol–Gel Derived Gate Dielectrics for Highly Stable Organic Thin-Film Transistors and Other Practical Applications

A novel fluorinated organic–inorganic (O–I) hybrid sol—gel based material, named FAGPTi, is successfully synthesized and applied as a gate dielectric in flexible organic thin-film transistors (OTFTs). The previously reported three-arm-shaped alkoxysilane-functionalized amphiphilic polymer yields a stable O–I hybrid material consisting of uniformly dispersed nanoparticles in the sol-state. Here, a fluorinated precursor is introduced into the system, making it possible to realize more stable spherical composites. This results in long-term colloidal stability (≈1.5 years) because composite growth is strongly inhibited by the presence of fluorine groups with intrinsically strong repulsive forces. Additionally, the FAGPTi film is easily deposited via thermally annealed sol–gel reactions; the films can be successfully fabricated through the printing method, and exhibit excellent flexibility and enhanced insulating properties compared to existing materials. OTFTs with FAGPTi layers show highly stable driving characteristics under severe bending conditions (1.9% strain). Integrated logic devices are also successfully operated with these OTFTs. Additionally, it can facilely be applied to amorphous indium-gallium-zinc-oxide (a-IGZO) TFT devices other than OTFT. Therefore, this synthetic strategy can provide useful insights into the production of functional O–I hybrid materials, enabling the efficient fabrication of electronic materials and devices exhibiting these properties.     

Homogeneous–Heterogeneous Hybrid Artificial Photosynthesis Induced by Organic Semiconductors with Controlled Surface Architectures

Photocatalysis is considered an effective approach for converting CO₂ into high-value-added chemicals. However, practical implementation of this technology is limited by the efficiency and stability of photocatalysis. Herein, an interfacial control strategy is proposed to optimize the homogeneous-heterogeneous hybrid photocatalysis by enhancing the interaction between light-harvesting semiconductors (LHS) and molecular active centers (MAC). Based on this strategy, self-assembled organic semiconductors with controlled surface architectures are constructed using 1,6-bis(phenylethynyl)pyrene building blocks to act as LHS. Combining with the classical MAC, an excellent CO₂ photoreduction performance is achieved with a CO turnover number of > 2980 maintaining long-term stability with a selectivity of > 90%, and an apparent quantum yield of > 2.3%. Theoretical calculations combined with in situ and transient spectroscopy studies reveal that the optimized biphase interface dominates the synergy between the homogeneous and heterogeneous photocatalysts. This strategy and the proposed mechanism of interactions will contribute to the design of future artificial photosynthesis systems.     

Synergistic Effect of Crosslinked Organic–Inorganic Composite Protective Layer for High Performance Lithium Metal Batteries

Maintaining a stable interface of lithium metal anodes (LMAs) by implementing a protective layer is a promising approach in extending the cycle life of lithium metal batteries (LMBs). Nevertheless, designing a protective layer with desired physicochemical properties is still a challenging task. Herein, an inorganic–organic composite protective layer consisting of fluorinated graphene oxide (FGO) (inorganic part) and polyacrylic acid (PAA) (organic part) that are in situ crosslinked via poly(ethylene glycol) diglycidyl ether (PEGDE) into a robust network is reported. The mechanical strength of FGO and the elasticity of the polymeric network jointly suppress the unwanted dendritic Li growth while fluorine-functional groups in FGO induce an LiF-enriched interface. This balanced inorganic–organic composite protective layer facilitates charge transfer kinetics for enhanced lithium-ion diffusion at the interface. Utilizing this protective layer, LMB full-cells with LiFePO₄ demonstrate negligible capacity loss for 100 cycles even under an extreme negative/positive capacity (N/P) ratio of 1.0. This study uncovers the possibility of highly robust, reliable LMBs by a sophisticatedly designed protective layer of widely used inorganic and organic components.     

In Situ Formation of Coordinated Polymer via Organic–Inorganic Hybridization Engineering Boosting High-Efficiency Potassium Storage

Organic redox-active molecules with merits of structure diversity and tunable properties are emerging as promising cathodes for the practical usage of potassium-ion batteries (PIBs). However, the inferior cycle stability and sluggish charge-carrier mobility are two main drawbacks hindering the practical application of organic cathode materials. Herein, highly conductive inorganic CuS is combined with small molecule-based redox species (perylene-3,4,9,10-tetracarboxylic dianhydride, PTCDA) to form a novel organic–inorganic hybrid cathode (PTCDA/CuS) for PIBs, which could undergo electrochemical-induced in situ self-transformation of a sulfur-linked and Cu²⁺-coordinated PTCDA polymer (labeled as Cu@PTCDA-SP). Benefiting from improved redox sites from activated carbonyl groups, high stability afforded by the sulfur-bridging, isotropic amorphous nature, and 3D cross-linked nanosheet morphologies, the resulting Cu@PTCDA-SP cathode exhibits a high-rate capacity involving trielectron enolization (vs 2-electron transformation in PTCDA monomers) and long-term cycle life (over 2800 cycles at 5 A g⁻¹). This organic–inorganic hybridized cathode is very promising for PIBs. Additionally, the self-transformation strategy provides new insight into the discovery of more electrochemically induced interaction between organic–inorganic hybrids toward high-performance secondary batteries.     

Mechanochemical Processing of Highly Conducting Organic/Inorganic Composites Exhibiting Spin Crossover–Induced Memory Effect in Their Transport Properties

Bistable multifunctional materials have great potential in a large variety of devices, from sensors to information units. However, the direct exploitation of spin crossover (SCO) materials in electronic devices is limited due to their very high electrical resistance (insulators). Beyond their intrinsic properties, SCO materials may also work as probes to confer bistability as switchable components in hybrid materials, as controlled by external stimuli acting upon the SCO spin state. Low resistance conductors with memory effect may be obtained from the incorporation of SCO probes into a conducting organic polymer matrix. This strategy appeared to be limited by the strict synthetic conditions, since polymerization reactions are harsh enough to attack the redox-unstable SCO component. Because of this, just a few successful examples have been reported. Here a versatile processing protocol is introduced to obtain SCO/conducting polymer composites exploiting a post-synthetic mechanochemical approach that can be applied to any SCO component and any organic polymer. This new protocol allows highly conducting films of polypyrrole, polyaniline, and poly(3,4-ethylenedioxythiophene) (PEDOT) to be obtained, with bulk conductivities as high as 1 S·cm⁻¹, and exhibiting a thermal hysteresis in their electrical conductivity above room temperature.