Preparation and promising optoelectronic applications of lead halide perovskite patterned structures:A review

Lead halide perovskites have received considerable attention from researchers over the past several years due to their superior optical and optoelectronic properties,because of which they can be a versatile platform for fundamental science research and applications.Patterned structures based on lead halide perovskites have much more novel properties compared with their more commonly seen bulk-,micro-,and nano-crystals,such as improvement in antireflection,light-scattering effects,and light absorption,as a result of their adjustability of spatial distributions.However,there are many challenges yet to be resolved in this field,such as insufficient patterned resolution,imperfect crystal quality,complicated preparation process,and so on.To pave the way to solve these problems,we provide a systematic presentation of current methods for fabricating lead halide perovskite patterned structures,including thermal imprint,use of etching films,two-step vapor-phase growth,template-confined solution growth,and seed-assisted growth.Furthermore,the advantages and disadvantages of these methods are elaborated in detail.In addition,thanks to the extraordinary properties of lead halide perovskite patterned structures,a variety of potential applications in optics and optoelectronics of these structures are described.Lastly,we put forward existing challenges and prospects in this exciting field.

Monocrotophos Molecularly Imprinted Microspheres Prepared by Precipitation Polymerization in Acetonitrile

Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (ACN) 60℃,24 h,using methacrylic acid (MAA),ethylene glycol dimethacrylate (EGDMA) and 2, 2-azobisiobutyronitrile (AIBN) as functional monomer,cross-linker and initiator,respectively.The recognition mechanism was elucidated by UV-vis spectra and computer modeling.Equilibrium binding experiment was employed to investigate the rebinding properties,Scatchard analysis showed that specific binding sites formed in the imprinted microspheres,and there were two kinds of binding sites,one was high binding sites,the other was low binding sites.This microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.

Detector-grade perovskite single-crystal wafers via stress-free gel-confined solution growth targeting high-resolution ionizing radiation

Solution-processed organic‒inorganic halide perovskite(OIHP)single crystals(SCs)have demonstrated great potential in ionizing radiation detection due to their outstanding charge transport properties and low-cost preparation.However,the energy resolution(ER)and stability of OIHP detectors still lag far behind those of melt-grown inorganic perovskite and commercial CdZnTe counterparts due to the absence of detector-grade high-quality OIHP SCs.Here,we reveal that the crystallinity and uniformity of OIHP SCs are drastically improved by relieving interfacial stress with a facial gel-confined solution growth strategy,thus enabling the direct preparation of large-area detector-grade SC wafers up to 4 cm with drastically suppressed electronic and ionic defects.The resultant radiation detectors show both a small dark current below 1 nA and excellent baseline stability of 4.0×10^(-8) nA cm^(-1) s^(-1) V^(-1),which are rarely realized in OIHP detectors.Consequently,a record high ER of 4.9% at 59.5 keV is achieved under a standard 241Am gamma-ray source with an ultralow operating bias of 5 V,representing the best gamma-ray spectroscopy performance among all solution-processed semiconductor radiation detectors ever reported.

Development of robust perovskite single crystal radiation detectors with high spectral resolution through synergetic trap deactivation and self-healing

Organic-inorganic halide perovskite single crystals(SCs)are promising materials for detecting ionizing radiation owing to their outstanding photoelectric conversion capability and inexpensive solution processability.However,the accuracy and stability of the detectors have been limited due to the charge traps and defects in SCs,especially when operated under high-precision photon-counting mode for energy spectrum acquisition.Here,we proposed a trap freezing deactivation route,which obviously suppressed dark current and noise by up to 97%and 92%,respectively.Furthermore,the bulk ion migration effect was essential for the ability to instantly self-heal defects induced by radiation damage at temperatures down to30C.Consequently,the detector exhibits a record high energy resolution of 7.5%at 59.5 keV for 241Amγ-ray source,which is the best solution-processed semiconductor radiation detectors at the same energy range.In addition,the detector maintains over 90%of its initial performance after 9 months of storage when tested in the air.Our results will represent a revision of the paradigm that high-spectral-resolution and robust radiation detectors can only be realized with high temperature grown inorganic semiconductor single crystals.

The regulatory roles of DDIT4 in TDCIPP-induced autophagy and apoptosis in PC12 cells

Tris(1,3-dichloro-2-propyl) phosphate(TDCIPP) is a commonly used organophosphatebased flame retardant and can bio-accumulate in human tissues and organs. As its structure is similar to that of neurotoxic organophosphate pesticides, the neurotoxicity of TDCIPP has raised widespread concerns. TDCIPP can increase neuronal apoptosis and induce autophagy.However, its regulatory mechanism remains unclear. In this study, we found that the expression upregulation of the DNA Damage-Inducible Transcript 4(DDIT4) protein, which might play essential roles in TDCIPP-induced neuronal autophagy and apoptosis, was observed in TDCIPP-treated differentiated rat PC12 cells. Furthermore, we determined the protective effect of the DDIT4 suppression on the autophagy and apoptosis induced by TDCIPP using Western blot(WB) and Flow cytometry(FACS) analysis. We observed that TDCIPP treatment increased the DDIT4, the autophagy marker Beclin-1, and the microtubule-associated protein light chain 3-II(LC_(3)II) expressions and decreased the mTOR phosphorylation levels. Conversely, the suppression of DDIT4 expression increased the p-mTOR expression and decreased cell autophagy and apoptosis. Collectively, our results revealed the function of DDIT4 in cell death mechanisms triggered by TDCIPP through the m TOR signaling axis in differentiated PC12 cells. Thus, this study provided vital evidence necessary to explain the mechanism of TDCIPP-induced neurotoxicity in differentiated PC12 cells.

Metal-halide perovskites for high-efficiency radiation shielding applications

The ionizing radiation possesses extremely strong penetration capability,which poses serious risk on the health of the human body and jeopardize electronics.Here the authors demonstrate that MAPbl3/epoxy composites prepared by a simple method show high radiation shielding performance.

基于土地利用变化情景的生态系统服务价值评估:以钱江源国家公园体制试点区为例

土地利用变化是生物多样性与生态系统服务变化的主要原因之一。评估土地利用变化对生物多样与生态系统服务影响对于政府决策具有重要作用。钱江源国家公园体制试点区是钱塘江的源头,也是国家的重点生态功能区。本研究以钱江源国家公园体制试点区为研究区,首先设计自然发展情景、规划情景、生态保护情景和开发利用情景等4种2025年不同土地利用变化情景,随后采用In VEST模型和CLUE-S模型分析不同情景下钱江源国家公园水资源供给、涵养水源、固碳释氧、土壤保持、环境净化和生境质量等生态系统服务及其价值变化。结果表明:(1)核心保护区和生态保育区的生态系统服务价值占钱江源国家公园总价值的88.30%。(2)生态保护情景下钱江源国家公园生态系统服务价值最高,有129.17亿元;规划情景下生态系统服务价值次之,有126.92亿元。(3)规划情景下钱江源国家公园水资源供给服务优于生态保护情景,其他生态系统服务则次于生态保护情景。考虑到钱江源国家公园为下游提供重要的水资源这一功能,将规划情景作为试点区2025年最优的土地利用变化情景。

钱江源国家公园体制试点区农户生计资本评价及其空间特征

本研究以钱江源国家公园体制试点区(以下简称为钱江源国家公园)为例,基于可持续生计分析框架,构建农户生计资本评价指标体系,运用熵权法、聚类分析和空间自相关分析,开展钱江源国家公园农户生计资本评价,并对其空间分布和集聚特征进行分析。结果表明:(1)不同农户类型的生计资本均值呈现非农户>兼业户>纯农户,非农户的人力资本、社会资本和物质资本远高于兼业户和纯农户;(2)不同农户类型资产等级划分差异显著,纯农户的中低资产较多,非农户的高资产较多,生计资本与生计活动类型密切相关;(3)农户生计资本总量在空间上呈现由西南向东北递增的趋势,何田乡生计资本较为均衡,齐溪镇、长虹乡和苏庄镇的生计资本搭配不合理;(4)不同功能区农户生计资本分布与功能定位和管理强度相关;(5)自然资本呈现显著空间自相关性,其余资本及总量空间自相关性不显著。最后,为改善钱江源国家公园农户生计状况提出了相关建议。

Atomistic Surface Passivation of CH_(3)NH_(3)PbI_(3) Perovskite Single Crystals for Highly Sensitive Coplanar-Structure X-Ray Detectors

Organic-inorganic halide perovskites(OIHPs)are recognized as the promising next-generation X-ray detection materials.However,the device performance is largely limited by the ion migration issue of OIHPs.Here,we reported a simple atomistic surface passivation strategy with methylammonium iodide(MAI)to remarkably increase the ion migration activation energy of CH_(3)NH_(3)PbI_(3)single crystals.The amount of MAI deposited on the crystal surface is finely regulated by a self-assemble process to effectively suppress the metallic lead defects,while not introducing extra mobile ions,which results in significantly improved dark current stability of the coplanar-structure devices under a large electric field of 100Vmm^(-1).The X-ray detectors hence exhibit a record-high sensitivity above 700,000μC Gy^(-1)_(air) cm^(-2)under continuum X-ray irradiation with energy up to 50 keV,which enables an ultralow X-ray detection limit down to 1.5 nGy_(air)s^(-1).Our findings will allow for the dramatically reduced X-ray exposure of human bodies in medical imaging applications.