Optoelectronic Materials Research Articles

Pnictogen Atom Substitution to Modify the Electronic and Magnetic Properties of SiS2${\rm SiS}_{2}$ Monolayer: A DFT Study

AbstractThe density functional theory (DFT) is employed to study the modulation of electronic and magnetic properties of monolayer through doping with pnictogen (P and As) atoms. monolayer is intrinsically non‐magnetic, exhibiting the semiconductor nature with indirect bandgap of 1.39(2.26) eV provided by standard(hybrid) functional. This 2D material is metallized under effects of single Si vacancy, single S vacancy, and pair Si─S vacancies. In the latter case, significant magnetism with a total magnetic moment of 1.55 is produced mainly by S atoms around the vacancy sites. The monolayer metallization takes place also when doping with P and As atoms at Si sublattice, preserving the nonmagnetic nature. Meanwhile, P and As substitution leads to the emergence of magnetism with total magnetic moments of 0.93 and 0.99 , respectively. Herein, magnetic properties are produced mainly by the outermost orbital of pnictogen impurities. Interestingly, the results assert the emergence of the half‐metallicity, which gives evidence of new highly spin‐polarized 2D materials. Further, doping with pair P/P, As/As, and P/As atoms are also considered with different doping configurations. It is found that the nonmagnetic semiconductor nature is preserved upon doping with pair pnictogen atoms, however, the indirect‐to‐direct gap transition is induced. Moreover, the energy gap exhibits large reduction between 51.80% and 77.70%. The findings in this work may suggest the formation of prospective optoelectronic and spintronic 2D materials by doping monolayer with pnictogen atoms.

First-principles calculations of the effect of vacancy defects on the optoelectronic and mechanical properties of the double perovskite Cs2NaInCl6

Abstract Cs2NaInCl6 have become a hot research topic in perovskite optoelectronic materials. However, there is no research on the vacancy properties of Cs2NaInCl6 at present. Herein，using density functional theory-based first-principles calculations, the impact of Cs, Na, In, and Cl single vacancies on the microstructure, electronic, optical, and mechanical properties of the double perovskite Cs2NaInCl6 were investigated. The research shows that the presence of vacancy defects leads to distortion of the Cs2NaInCl6 double perovskite structure and an increase in the unit cell volume. Cs vacancy (VCs) and Na vacancy (VNa) cause an increased band gap for Cs2NaInCl6, by 2.92eV and 3.1eV respectively, without changing the characteristics of the initial direct band gap; VIn and VCl cause the intrinsic semiconductor Cs2NaInCl6 to transform into p-type and n-type semiconductors, respectively, altering the conductivity of Cs2NaInCl6. In terms of optical properties, different vacancy defect systems exhibit different absorption abilities in the visible and ultraviolet light ranges. The defect system overall improves light absorption in the low energy region, and as the incident photon energy increases, the material exhibits the best optical performance at around 15eV. In addition, it is found that VCs, VNa, and VIn caused blue shift in the absorption edge of Cs2NaInCl6, while VCl caused red shift in the absorption edge. In terms of mechanical properties, defects cause varying degrees of reduction in Young's modulus (E), shear modulus (G), and bulk modulus (B) of Cs2NaInCl6, which to some extent alters the mechanical properties of Cs2NaInCl6. These research results provide theoretical guidance for understanding the influence of vacancies on the properties of Cs2NaInCl6 double perovskite and optimizing the performance of perovskite optoelectronic devices, and they also enhance its applications in photovoltaic cells, optoelectronic sensors, and other optoelectronic coupling devices.

Regio- and Chemo-selective C-H Arylation of 3-Bromothiophene: A Synthesis Shortcut to Versatile π-Conjugated Building Blocks for Optoelectronic Materials.

Unlike traditional multi-step synthetic approaches, we developed a single-step synthesis of versatile π-conjugated building blocks bearing post-functionalizable C-H and C-Br bonds. Direct C-H arylation of 3-bromothiophene with various iodo(hetero)aryls was successfully carried out with good regio- and chemo-selectivity. Under optimized reaction conditions, 20 new compounds were facilely prepared in yields up to 91%. One of the obtained compounds was demonstrated to further extend its conjugation length using a succinct synthetic plan to create two symmetrical oligo(hetero)aryls (MLC01 and MLC02) that were fabricated as effective hole-transporting materials (HTM) for perovskite solar cells (PSC). PSC devices utilizing MLC01 as hole-transport layer displayed promising power conversion efficiencies of up to 17.01%.

Comparative Analysis of Thin and Thick MoTe2 Photodetectors: Implications for Next-Generation Optoelectronics

Due to its outstanding optical and electronic properties, molybdenum ditelluride (MoTe2) has become a highly regarded material for next-generation optoelectronics. This study presents a comprehensive, comparative analysis of thin (8 nm) and thick (30 nm) MoTe2-based photodetectors to elucidate the impact of thickness on device performance. A few layers of MoTe2 were exfoliated on a silicon dioxide (SiO2) dielectric substrate, and electrical contacts were constructed via EBL and thermal evaporation. The thin MoTe2-based device presented a maximum photoresponsivity of 1.2 A/W and detectivity of 4.32 × 108 Jones, compared to 1.0 A/W and 3.6 × 108 Jones for the thick MoTe2 device at 520 nm. Moreover, at 1064 nm, the thick MoTe2 device outperformed the thin device with a responsivity of 8.8 A/W and specific detectivity of 3.19 × 109 Jones. Both devices demonstrated n-type behavior, with linear output curves representing decent ohmic contact amongst the MoTe2 and Au/Cr electrodes. The enhanced performance of the thin MoTe2 device at 520 nm is attributed to improved carrier dynamics resulting from effective electric field penetration. In comparison, the superior performance of the thick device at 1064 nm is due to sufficient absorption in the near-infrared range. These findings highlight the importance of thickness control in designing high-performance MoTe2-based photodetectors and position MoTe2 as a highly suitable material for next-generation optoelectronics.

Advances in Organic Materials for Next-Generation Optoelectronics: Potential and Challenges

This review provides a comprehensive overview of recent advancements in the synthesis, properties, and applications of organic materials in the optoelectronics sector. The study emphasizes the critical role of organic materials in the development of state-of-the-art optoelectronic devices such as organic solar cells, organic thin-film transistors, and OLEDs. The review further examines the structure, operational principles, and performance metrics of organic optoelectronic devices. Organic materials have emerged as promising candidates due to their low-cost production and potential for large-area or flexible substrate applications. Additionally, this review highlights the physical mechanisms governing the optoelectronic properties of high-performance organic materials, particularly photoinduced processes relevant to charge carrier photogeneration. It discusses the unique benefits of organic materials over traditional inorganic materials, including their light weight, simple processing, and flexibility. The report delves into the challenges related to stability, scalability, and performance, while highlighting the wide range of electronic properties exhibited by organic materials, which are critical for their performances in optoelectronic devices. Furthermore, it addresses the need for further research and development in this field to achieve consistent performance across different types of devices.

Natural and Nature-Inspired Biomaterial Additives for Metal Halide Perovskite Optoelectronics.

This comprehensive review meticulously categorizes and discusses the applications of diverse biomaterials, specifically natural and nature-inspired synthetic materials in metal halide perovskite optoelectronics. Applications range from solar cells to light-emitting diodes, photodetectors, and X-ray detectors. Emphasis is placed on the intricate interactions between bio-additives and perovskite crystals, highlighting their influence on the grain size, crystal orientation, grain boundaries, and surface passivation. This review also explores the advantages and disadvantages of each natural or nature-inspired material and their unique properties compared with conventional additives. Special attention is given to the mechanistic and functional viewpoints, showing how these biomaterials enhance device performance. Through additive engineering with ecofriendly biomaterials, defects in metal halide perovskite thin films can be effectively passivated, thus extending the photostability or in some cases mechanical flexibility of devices. This review provides valuable insights for selecting and designing next-generation biomaterial additives, offering new prospects for achieving high-performance perovskite layers and advancing the field of peorvskite- based optoelectronics.

Investigation of the Optoelectronic, γ‐Attenuation, and Thermodynamic Properties of Novel MnGa2P3H4NO14 for Energy Applications: A DFT Study

ABSTRACTTransparent conducting oxides (TCOs) from the semiconductor family have garnered considerable interest due to the growing popularity of optoelectronic and thermodynamical applications. Our present study has presented findings on the electronic, optical, and thermodynamic characteristics of spinel oxide MnGa2P3H4NO14; using density functional theory (DFT), we utilized first‐principles calculations carried out with the Wien 2 k software package. The calculations were performed using the generalized‐gradient‐approximation plus Hubbard potential U (GGA+U) method for the doped materials. The band structure calculation reveals that the parent compound exhibits a semiconducting nature and a direct band gap of 2.9 and 1.7 eV for spin‐up and down channels, respectively. The stability of the material is assessed by evaluating its formation energies, which reveal that spinel oxide exhibits the highest stability. The thermodynamic properties are determined using the quasiharmonic Debye model, implemented in the GIBBS 2 code. Furthermore, the quasiharmonic Debye model examines the pressure and temperature dependence of all parameters related to the investigated spinel oxides. In order to evaluate the effectiveness of the radiation shielding, we computed the mass attenuation coefficient for the XCOM program that was investigated from the sample. In addition, linear attenuation, half‐value layer, and mean free path values have been evaluated. A thorough investigation into the dielectric function's optical characteristics was conducted. It has been found that the dielectric function exhibits a wide range of energy transparency. The discovery of UV‐absorbing materials with extremely narrow band gaps suggests their potential use in optoelectronic and solar cell applications. These results provide solid proof and motivation for seeking cutting‐edge optoelectronic materials and technology.

Unlocking Full-Spectrum Brilliance: Dimensional Regulation in Lead-Free Metal Halides for Superior Photoluminescence.

Lead-free metal halides with tunable structures have emerged as a new class of optoelectronic materials. The arrangement of metal halide polyhedra defines their structural dimensionality and serves as a key factor influencing their optical properties. To investigate this, we synthesized four different antimony (Sb)-doped indium (In)-based metal halides, all of which possess zero-dimensional (0D) electronic structures but exhibit 3D, 2D, 1D, and 0D structural dimensionality at the molecular level. With a decreasing of structural dimensionality, their self-trapped exciton (STE) emission shows a red shift with peak position from 496 to 663 nm. We revealed that the red shift is caused by increased distortion of [SbCl6]3- octahedra as the structural dimensionality decreases, leading to lowered energy levels of STE and a corresponding red shift. The tunable STE emission makes these metal halides promising for anticounterfeiting and white LED applications. These findings provide a new strategy for tuning STE emission in lead-free metal halides.

Fluorescence Enhancement of Nonemissive Monodeprotonated Luteolin in a Poly(vinyl alcohol) Film.

Solid polymer matrixes can modulate the electronic states of embedded chromophores and have been widely used in flexible optoelectronic and optical materials. Luteolin is one of the most common natural flavonoids, and its neutral and monodeprotonated forms are nonemissive in aqueous solution induced by ultrafast excited-state proton transfer (ESPT) followed by nonradiative relaxation. In this study, we have incorporated luteolin into poly(vinyl alcohol) (PVA) films and studied their fluorescence behaviors. Neutral and one monodeprotonated luteolin coexist in the PVA film. Weak steady-state fluorescence of neutral luteolin peaking at about 440 nm is observed for the first time. In addition, the monodeprotonated luteolin in PVA film exhibits obvious fluorescence peaking at 500 nm, with a fluorescence quantum yield of as high as 0.4 and a fluorescence lifetime of as long as 2.4 ns. Time-dependent density functional theory calculations have determined that the ESPT of neutral luteolin is barrierless but that of monodeprotonated luteolin needs to surmount a barrier, explaining their distinct emission properties. These results indicate the modulation ability of the PVA film in both ground-state deprotonation and ESPT, broadening the application areas of the solid polymer matrix.

Prominent cryogenic fluorescence temperature sensing and superior room-temperature photochromism in Bi/Eu codoped KNN transparent-ferroelectric ceramics

The growing demand for the miniaturization and multifunctionality of optoelectronic devices has promoted the development of transparent ferroelectrics. However, it is difficult for the superior multiple optical properties of these materials to be compatible with the excellent ferroelectricity and piezoelectricity in transparent ceramics. Here, we successfully synthesized Bi/Eu codoped eco-friendly K0.5Na0.5NbO3 transparent-ferroelectric ceramics with photoluminescence (PL) behavior, photochromic (PC) reactions and temperature-responsive PL. Based on the distinct optical properties of ceramics at different temperature ranges (room temperature and ultralow temperature), high utilization of multiple optical functions was realized. At room temperature, the PC behavior induced PL modulation contrast reaches 75.2% (at 592 nm), which can be applied in the optical information storage field. In the ultralow temperature range, the ceramics exhibit excellent sensitivity (with a maximum relative sensitivity of 26.32%/K) via fluorescence intensity ratio technology and exhibit great application potential in noncontact optical temperature measurements. Additionally, the change in the PL intensity at different wavelengths (I614/I592) can serve as a reliable indicator for detecting the occurrence of the phase transition from rhombohedral to orthorhombic at low temperature. This work provides a feasible paradigm for realizing the integration of ferroelectricity and multifarious optical properties in a single optoelectronic material.

Band Gap Engineering and Frequency Dispersive Dielectric Properties of Rare Earth (Sm3+) Modified Ba0.8Sr0.2TiO3 Ceramics for Potential Use as an Optoelectronic Materials

Lead free perovskite materials have the capability to be used in various multifunctional applications. In this regard, dielectric and light absorption properties of Sm modified Ba0.8-xSmxSr0.2TiO3 have been explored. The dielectric constant has been estimated to be 2788 for Ba0.77Sm0.03Sr0.2TiO3. The optical band gap of all prepared samples has been evaluated by employing Tauc plot method and observed that the band gap varies 3.13-2.97 eV with the increase in Sm concentration. In brief, the present study reports the physical properties of Ba0.8-xSmxSr0.2TiO3 ceramics which open window for possible use of it as lead-free optoelectronic material.

Acid‐Mediated Oxidative C‐H Phosphorylation of Quinoxalines and Quinoxalin‐2(1H)‐one

Quinoxaline is a chemical moiety known for its diverse physicochemical and biological properties, making it the focus of extensive research. Over the past few decades, quinoxaline scaffolds have been utilized in the design and development of various bioactive molecules, dyes, fluorescent materials, electroluminescent materials, organic sensitizers for solar cells, and polymeric optoelectronic materials. Herein, we present a metal‐free and rapid protocol for the phosphorylation of quinoxalines and quinoxalin‐2(1H)‐one. This method employs oxygen as an oxidant under ambient temperature and atmospheric pressure, with experimental evidence indicating the absence of radical involvement. Our methodology provides range of phosphorylated quinoxalines and quinoxaline‐2(1H)‐one in yields ranging from 47% to 99%.

Boosting FRET Efficiency of Chromophores with Aggregation-Caused Quenching by a Crystallization-Induced Precise Co-assembly Strategy.

Förster resonance energy transfer (FRET) plays a critical role in organic optoelectronic materials. However, developing facile and effective strategies to achieve high-efficiency energy harvesting of chromophores with aggregation-caused quenching (ACQ) remains an appealing yet challenging task, that has not yet been explored. Herein, a subtly strategy, crystallization-induced precise co-assembly (CIPCA) involving a molecular "lightening agent," to effectively improve FRET efficiency of ACQ chromophores is developed. Bis(phenylethynyl)anthracene (BPA) and bis(phenylethynyl)naphthacene (BPN) with significant ACQ effect are chosen as representative FRET donor and acceptor, respectively, and weakly-fluorescent octafluoronaphthalene (OFN) acted as the "lightening agent." Thanks to precise co-assembly with OFN, the PLQY of solid BPA is enhanced by 107%, and the BPN powder can be unprecedentedly lighted. More importantly, through such powerful CIPCA, the monotonous and weak emission for BPA@BPN can be remarkably regulated to colorful and much brighter ones with FRET efficiency improvement of as high as 180-270%. An in-depth understanding of FRET regulation is elucidated through a precise correlation of the supramolecular structures and properties. Such achievements allow to successfully fabricate distinct multi-stimuli-responsive fluorescent patterns and highly-emissive colorful flowers with high flexibility. This research provides an efficient strategy to improve the FRET efficiency of ACQ pairs.

Interplay Between the N→C Dative Bond, Intramolecular Chalcogen Bond and π Conjugation in the Complexes Formed by Cyclo[18]carbon and C14 Polyyne with 1,2,5-Chalcogenadiazoles.

The N→C dative bond (DB), intramolecular chalcogen bond and π conjugation play important roles in determining the structures and properties of some molecular carbon materials and organic/polymeric photovoltaic materials. In this work, the interplay between the N→C DB, intramolecular chalcogen bond and π conjugation in the complexes formed by cyclo[18]carbon and C14 polyyne with 1,2,5-chalcogenadiazoles has been investigated in detail by using reliable quantum chemical calculations. This study has made four main findings. First, only the Te-containing complexes bound by N→C DBs are much more stable than their corresponding van der Waals (vdW) complexes. Second, in addition to through-bond π conjugations, through-space π conjugations also exist in some Se/Te-containing complexes bound by N→C DBs. Third, the cooperativity between intramolecular chalcogen bond, π conjugation between two monomers and N→C DB is not very strong and can be ignored. Fourth, compared to π conjugations, intramolecular Ch⋅⋅⋅C (Ch=O, S, Se, Te) chalcogen bonds play a secondary role in stabilizing the complexes bound by N→C DBs. These findings clearly indicate that the role of "conformational lock", popular in the field of organic optoelectronic materials, may have been greatly overestimated.

Application and Research Progress of Perovskite in the Field of Optoelectronic Materials

Perovskite refers to a class of materials with the formula of ABO3. These oxides were first discovered in calcium titanate compounds. Perovskite materials have attracted widespread attention in the field of contemporary photovoltaic research due to their excellent photovoltaic properties, heralding their potential as protagonists of a new generation of photovoltaic materials. Nevertheless, the stability of perovskite materials needs to be enhanced. In addition, reducing the toxicity of the materials is a key challenge in advancing their commercialization. Currently, the rapid development of perovskite in the field of optoelectronics and its unique combination of properties have laid a solid foundation for its position as a mainstream optoelectronic material of the future. Therefore, this work focuses on the properties and applications of perovskite optoelectronics. With deeper scientific research and technological innovation, perovskites have the potential to overcome existing limitations and move towards large-scale commercial production. In the future, the further application of perovskite optoelectronic materials would have far-reaching implications for the global energy transition and environmental protection.

LaAgSiS4: Increasing Optical Birefringence in Rare Earth Chalcogenide by Addition of Planar [AgS3] Groups.

Optoelectronic materials with excellent birefringent properties are of significant importance in the fields of optical communications and laser technology. Recently, rare earth (RE) chalcogenides with anisotropic [RESn] groups have been proven to be high-performance infrared birefringent materials. Herein, we demonstrate that the addition of planar groups can further increase the birefringence in RE chalcogenides, as realized by incorporating planar [AgS3] groups into the RE-I-IV-S4 family for the first time. The newly obtained LaAgSiS4 compound shows higher polarity anisotropy than its homologue LaLiSiS4 and LaKSiS4, which resulted in a larger birefringence (0.12@600 nm) at least twice as large as that of the latter two compounds (0.05/0.06@600 nm). The structure-property relationship of LaAgSiS4 was investigated through structural analysis and first-principles calculations. The results indicate that the increased optical birefringence in LaAgSiS4 originates from the synergic effects of the distorted [LaSn] polyhedra and planar [AgS3] triangles. This work provides an effective strategy for enhancing optical birefringence in IR chalcogenides.

Enhancing optical properties of Ba-Ni ferrite through nonmagnetic ion doping for sustainable green technologies and renewable energy applications

Barium ferrite powder was produced using a standard ceramic procedure, and its structure and optical properties were investigated. X-ray diffraction analysis (XRD) showed that the powder had a w-type hexagonal structure. The crystallite size was at approximately 35–36 nm, with bulk density and lattice constants increasing as zinc concentration rose. Conversely, X-ray density and porosity decreased with the increasing zinc concentration. This material has useful optical properties, as well as the standard ferrimagnetic properties of barium ferrite, which make it suitable for use in recording media. Ferrimagnetic behavior, which is useful for recording media, occurs because the powder's crystallites have their unit cell axes aligned. Up to the near-infrared part of the spectrum, the powder was found to have a very low absorption coefficient. Both of these properties—an arrangement that gives rise to ferrimagnetism and a corresponding low optical density—make barium ferrite very attractive for high-density recording and microwave applications. Fourier transform infrared spectra of the samples were recorded in the wavenumber range of 400–4000 cm−1 and supported the X-ray diffraction findings by confirming the idea of the formation of W-type hexagonal ferrite by the presence of two prominent peaks at 454 and 591 cm−1 in the FTIR spectra. Zinc addition was also found to enhance the optical properties of the material. The UV–VIS analysis confirms that the band gap energy of Ba-Ni ferrite was indeed reduced by zinc doping. Values decrease from 3.34 eV to 3.20 eV for direct transitions and from 2.96 eV to 2.79 eV for indirect transitions, using Tauc equation. That means that zinc doping enhances the optical properties of Ba ferrite without affecting the hexagonal structure of Ba-Ni ferrite. Moreover, key parameters of optical performance such as the dielectric constant, the extinction coefficient, the penetration depth, and the refractive index show a dramatic increase with a rise in zinc concentration. These attributes make zinc-doped Ba-Ni ferrite a promising optoelectronic material. The material also showed high absorbance in the wavelengths ranging from 334 to 338 nm, which makes it good for the solar cell applications. Overall, zinc-doped Ba-Ni ferrite is a good candidate for sustainable and renewable energy applications. Our study of the optical properties of barium ferrite up to the near-infrared part of the spectrum demonstrated that the powdered material has a very low absorption coefficient. Indeed, the combination of ferrimagnetism and low optical density makes barium ferrite particularly appealing for use in high-density recording and microwave technology applications.

Exploring Aqueous Solution‐Processed Pseudohalide Rare‐Earth Double Perovskite Ferroelectrics toward X‐Ray Detection with High Sensitivity

AbstractThree‐dimensional (3D) pseudohalide rare‐earth double perovskites (PREDPs) have garnered significant attention for their versatile physical properties, including ferroelectricity, ferroelasticity, large piezoelectric responses, and circularly polarized luminescence. However, their potential for X‐ray detection remains unexplored, and the low Curie temperature (TC) limits the performance window for PREDP ferroelectrics. Here, by applying the chemical regulation strategies involving halogen substitution on the organic cation and Rb/Cs substitution to the PREDP [(R)‐M3HQ]2RbEu(NO3)6 [(R)‐M3HQ=(R)‐N‐methyl‐3‐hydroxylquinuclidinium] with a low TC of 285 K, a novel 3D PREDP ferroelectric [(R)‐CM3HQ]2CsEu(NO3)6 [(R)‐CM3HQ=(R)‐N‐chloromethyl‐3‐hydroxylquinuclidinium] are successfully synthesized, for which the TC reaches 344 K. More importantly, such a strategy endowed [(R)‐CM3HQ]2CsEu(NO3)6 with notable X‐ray detection capabilities. Centimeter‐sized [(R)‐CM3HQ]2CsEu(NO3)6 single crystals fabricated from aqueous solutions demonstrated a sensitivity of 1307 μC Gyair−1 cm−2 and a low detectable dose rate of 152 nGyair s−1, the highest sensitivity reported for hybrid double perovskite ferroelectric detectors. This work positions PREDPs as promising candidates for the next generation of eco‐friendly optoelectronic materials and also offers substantial insights into the interaction between structure, composition, and functionality in ferroelectric materials.

Exploring Aqueous Solution-Processed Pseudohalide Rare-Earth Double Perovskite Ferroelectrics toward X-Ray Detection with High Sensitivity.

Three-dimensional (3D) pseudohalide rare-earth double perovskites (PREDPs) have garnered significant attention for their versatile physical properties, including ferroelectricity, ferroelasticity, large piezoelectric responses, and circularly polarized luminescence. However, their potential for X-ray detection remains unexplored, and the low Curie temperature (TC) limits the performance window for PREDP ferroelectrics. Here, by applying the chemical regulation strategies involving halogen substitution on the organic cation and Rb/Cs substitution to the PREDP [(R)-M3HQ]2RbEu(NO3)6 [(R)-M3HQ=(R)-N-methyl-3-hydroxylquinuclidinium] with a low TC of 285 K, a novel 3D PREDP ferroelectric [(R)-CM3HQ]2CsEu(NO3)6 [(R)-CM3HQ=(R)-N-chloromethyl-3-hydroxylquinuclidinium] are successfully synthesized, for which the TC reaches 344 K. More importantly, such a strategy endowed [(R)-CM3HQ]2CsEu(NO3)6 with notable X-ray detection capabilities. Centimeter-sized [(R)-CM3HQ]2CsEu(NO3)6 single crystals fabricated from aqueous solutions demonstrated a sensitivity of 1307 μC Gyair -1 cm-2 and a low detectable dose rate of 152 nGyair s-1, the highest sensitivity reported for hybrid double perovskite ferroelectric detectors. This work positions PREDPs as promising candidates for the next generation of eco-friendly optoelectronic materials and also offers substantial insights into the interaction between structure, composition, and functionality in ferroelectric materials.

Structural Design of Hybrid Manganese(II) Halides for High Quantum Efficiency and Specific Response to Methanol.

Manganese(II) halides have been a new generation of optoelectronic materials due to their fascinating luminescent properties, however, lacking specific solvent-responsive analogues with high quantum efficiency. Herein, we prepared three single crystals, [Pr(MIm)2][MnBr4] ([Pr(MIm)2]2+ = 1,3-di(methylimidazolium)-propane, Compound 1), [Pr(EIm)2][MnBr4] ([Pr(EIm)2]2+ = 1,3-di(ethylimidazolium)-propane, Compound 2), and [Bu(MIm)2][MnBr4] ([Bu(MIm)2]2+ = 1,4-di(methylimidazolium)-butane, Compound 3), where different Bola-type cations were chosen as organic components to separate [MnBr4]2- tetrahedrons. All three compounds emitted bright green light with excellent quantum yields of 95.3, 80.0, and 96.2%, benefiting from the large Mn···Mn distance. More interestingly, Compound 3 showed a highly selective response to methanol in a series of tested organic solvents, with a rapid and reversible change in emission color from green to red. The single crystal of [Bu(MIm)2][MnBr4]·CH3OH with red emission proved that the luminescence switching was attributed to the adsorption of CH3OH molecules into the lattice space in the form of the O-H···Br hydrogen bonds. To our knowledge, for tetrahedrally coordinated Mn(II) species, the reversible emission color switching between green and red triggered by a solvent without the change of coordination number is achieved for the first time, providing promising applications for the specific detection of methanol.