Potential Applications In Optoelectronic Fields Research Articles

Controllable preparation of high-quality MAPbCl3 perovskite single crystal sheets

Hybrid perovskite CH3NH3PbCl3 single crystals have received much attention in the field of photodetectors due to their outstanding optoelectronic properties. Herein, a simple growth method of CH3NH3PbCl3 single crystal sheets was demonstrated in detail. The steady-state solution micro-reaction method with the small-hole rate control and the liquid-surface height control effectively solves the disadvantages of liquid- and gas-phase methods and realizes the preparation of a CH3NH3PbCl3 single crystal sheet with the controllable growth rate, size, and thickness, and good crystal quality and high crystallinity. Moreover, photodetectors based on one CH3NH3PbCl3 single crystal perovskite were fabricated with the responsivity of 80 mA/W under 395 nm light at 5 V. Meanwhile, a rise time of 22.3 µs and a fall time of 16.5 µs were obtained, indicative of a relatively fast response. These findings demonstrate that the CH3NH3PbCl3 single crystal perovskite have great potential applications in optoelectronic fields.

Lead-Free Hybrid Organic-Inorganic Ferroelectric: (3,3-Difluoropyrrolidinium)2ZnCl4·H2O.

Hybrid organic-inorganic ferroelectrics (HOIFs) have a wide range of applications in the optoelectronic field in terms of rich optoelectronic properties. Particularly, lead-free HOIFs have attracted extensive attention due to their environmental friendliness, low heavy metal toxicity, and low synthesis cost. However, there are few reports about Zn-based HOIFs due to their uncontrollable ferroelectric synthesis and other reasons. Here, we designed and synthesized a zinc-based zero-dimensional (3,3-difluoropyrrolidine)2ZnCl4·H2O (DFZC) single crystal, which undergoes a phase transition from ferroelectric to paraelectric phase (space group from Pna21 to Pnma) at 295.5 K/288.9 K during the heating/cooling process. The systematic study shows that the ferroelectric phase transition is a displacive type. The ferroelectric hysteresis loop of DFZC was obtained by the double-wave method and the Sawyer-Tower method, which has a spontaneous polarization (Ps) of ∼0.4 μC/cm2. This work reveals the strategy to design new zinc-based lead-free HOIFs for potential applications in optoelectronic fields.

The electric and optical properties of Bi4Ti3O12–Na0.5Bi2.5Nb2O9:Sm composite ceramics

Bismuth layer-structured ferroelectrics with a high Curie temperature (Tc) have great potential applications in optoelectronic fields. Sm doped (10-x)Bi4Ti3O12-xNa0.5Bi2.5Nb2O9 ((10-x)BIT-xNBN:Sm) composite ceramics have been prepared. The effect of NBN content on the microstructure, electrical properties, photoluminescence (PL) and photochromic (PC) properties of the ceramics have been investigated. It is found that the composite ceramics exist with BIT and NBN phases and 1BIT-9NBN:Sm ceramics have the best comprehensive electrical properties (saturated polarization, d33 = 10 pC/N). Furthermore, the PC and fluorescence modulation performances are dependent on the oxygen vacancy content of composite ceramics. Reversible PC reaction and fast response time as short as 1s have been achieved. Moreover, the influence of natural light on PC reaction has been properly eliminated. The research results indicate that regulating the compositions of (10-x)BIT-xNBN:Sm can not only optimize the electrical properties but also the PC performances. A vivid display via the quick PC reaction has been demonstrated.

Study on the Luminescence Properties of ZnS:Mn2+ Particles by High Temperature Solid Phase Method

ZnS has attracted wide attention for its potential applications in optoelectronic fields, such as solid-state lighting, fluorescent probes, electroluminescent devices and field emission displays. In this work, Mn2+-doped ZnS with hexagonal structure were prepared by high temperature solid phase method using MnCO3 as manganese source, and the effect of Mn2+ doping on ZnS was studied. The results show that the particle shape of ZnS doped with Mn2+ is hexagonal structure, Mn2+ doping changes the position and intensity of ZnS absorption spectrum and photoluminescence band. The absorption peak at 340 nm progressively moves to the right as Mn2+ doping rises, a new conspicuous absorption peak forms in the visible area, and the maximum photoluminescence intensity of ZnS:Mn2+ steadily increases. However, when the Mn2+ doping exceeds the ratio of 4 at.%, the photoluminescence intensity showed a decreasing trend. This indicates that the number of effective emission centers reaches the maximum when the doping concentration of Mn2+ is the most suitable.

Recent Advances in 1D Organic Solid‐State Lasers

AbstractOrganic solid‐state lasers (OSSLs) based on 1D organic crystals have attracted broad attention from researchers owing to the importance of potential applications in optoelectronic fields. 1D OSSLs can be fabricated from various organic molecules under the function of weak intermolecular interactions via numerous methods. The lasing performance of 1D OSSLs can be tuned toward novel optoelectronic applications by modifying the primary 1D morphology through constructing heterogeneous 1D architectures. Here, the recent advances of 1D OSSLs from the aspects of materials, fabrication methods, as well as some enlightening examples of 1D OSSLs with advanced laser performances are reviewed, and an outlook is given providing inspiration for the future development of 1D OSSLs with desired performances.

Assembling SnO Nanosheets into Microhydrangeas: Gas Phase Synthesis and Their Optical Property

Abstract Large scale SnO microhydrangeas are obtained successfully through thermally evaporating of SnO2 powder wrapped by a filter paper at 1050°C and using gold coated Si wafer as the substrate. The as-obtained SnO microhydrangeas are consisted of many thin nanosheets with the thicknesses of 30–60 nm and the diameters of 500–600 nm. A vapor-liquid-solid (VLS) growth mechanism for the as-synthesized SnO microhydrangeas was proposed based on experimental results. Photoluminescence spectrum (PL) shows that there is a strong sharp ultraviolet emission peak at 390 nm, revealing that these three-dimensional SnO microhydrangeas may have potential applications in optoelectronic fields.

Characterization and properties of semicrystalline and amorphous perfluoropolymer: poly(perfluoro‐2‐methylene‐1,3‐dioxolane)

The low and the high molecular weight poly(perfluoro‐2‐methylene‐1,3‐dioxolane)s were prepared using perfluorobenzoyl peroxide as a free radical initiator. Both polymers obtained were semicrystalline and insoluble in organic solvents. The glass transition temperatures (Tg) of polymers obtained were 94–106°C, and their melting points were 224–229°C. Wide‐angle X‐ray diffraction measurements showed that polymers as prepared are semi‐crystalline (21% crystalline fraction) and the crystallinity increased to 47% after annealing at 170°C. However, the films prepared by heating (at 230–250°C) and pressing of the high molecular weight polymers are transparent and flexible. The refractive index of the film is 1.3320 and 1.3245 at 533 and 1546 nm, respectively. The transparent polymer films did not recrystallize while annealing below Tg, and they are chemically and thermally stable. This polymer may have potential applications in optoelectronic fields. Copyright © 2011 John Wiley & Sons, Ltd.

New low bandgap molecules based on ethylene-separated benzothiadiazoles: synthesis and bandgap comparison

New ethylene-separated benzothiadiazoles were synthesized for the first time by using a facile procedure, and they showed lower bandgaps than the reported benzothiadiazole-containing compounds. This new benzothiadiazole-containing unit could be introduced into the backbone of the π-conjugated small molecules or polymers to develop new materials with a low bandgap that may have potential applications in optoelectronic fields.

Synthesis and Functional Properties of Symmetrically Naphthyl‐Based Oligoarylenes with High Glass‐Transition Temperatures

AbstractSymmetrically naphthyl‐based π‐conjugated oligoarylenes, OPP(4)Ph‐TNp, OPP(4)An‐TNp and OPP(4)OX‐TNp have successfully been synthesized by a divergent approach using Pd‐catalyzed Suzuki cross‐coupling reaction of diiodo‐ or dibromo‐oligoarylene and arylboronic acid as a key step. Their optical, electrochemical and thermal properties have also been characterized. These newly synthesized naphthyl‐based oligoarylenes show highly morphological (Tg 149–187°C) and thermal (Tdec 509–597°C) stabilities as well as exhibit potential applications in optoelectronic fields.