基于全无机CsPbBr3钙钛矿太阳能电池的光电性能研究

钙钛矿太阳能电池具有制作工艺简单和光电转换效率高等优点,成为光伏领域研究的热点。而全无机钙钛矿太阳能材料CsPbBr₃具有较强的稳定性,是具有竞争力的钙钛矿光吸收材料。主要利用SCAPS-1D软件构建了FTO/TiO₂/CsPbBr₃/Cu₂ZnSnS₄(CZTS)/Ag平面异质结结构。研究了全无机钙钛矿材料CsPbBr₃厚度和带隙对钙钛矿太阳能电池的影响。     

GdI3:Ce晶体的生长及其闪烁性能研究

通过坩埚下降法生长GdI₃:2%Ce及无掺杂GdI₃闪烁晶体, 得到ϕ15 mm×20 mm的晶体毛坯, 从中加工出尺寸分别为12 mm×10 mm×2.5 mm和11 mm×8 mm×2.5 mm的无包裹体、无开裂的晶体样品, 封装后检测该晶体光学性能。XRD分析结果表明: 掺杂晶体GdI₃:2%Ce与无掺杂GdI₃晶体结构相同。X射线激发发射(XEL)和紫外激发发射谱(PL)测试结果显示: GdI₃:2%Ce晶体在450~700 nm有宽带发光峰, 发光峰位分别位于520 nm和550 nm, 对应于Ce³⁺的5d-4f跃迁发光。以550 nm为监控波长, 测得在紫外激发下存在三个激发峰, 分别位于262、335和440 nm。GdI₃:2%Ce晶体在¹³⁷Cs源伽马射线(662 keV) 激发下能量分辨率为3.4%, 通过高斯拟合得到的衰减时间为58±3 ns。研究表明, GdI₃:2%Ce晶体是一种良好的伽马和中子探测材料, 具有广泛的应用前景。     

过饱和析晶法制备全无机钙钛矿CsPbX3及其性能

近年来,全无机铅卤钙钛矿材料(CsPbX3)因其优异的光学性能和相对于有机-无机杂化钙钛矿更好的稳定性等优势,从各类钙钛矿中脱颖而出,成为当前最具潜力的光电材料之一.相对于制备条件苛刻的高温热注入法,采用工艺简单易操作室温过饱和析晶法制备了一系列CsPbX3全无机钙钛矿材料,并探究了配体、提纯次数、反应温度、保存时间等...     

区熔法制备金属硫化物Ag2S及其热电性能研究

金属硫化物Ag2S具有优异的物理化学性能,在催化、传感及光电子等领域具有广阔的应用空间.本工作利用一种区熔技术制备了尺寸为?18 mm×50 mm的Ag2S并对其潜在热电性能进行了研究.Ag2S在450 K以下具有标准的 α-Ag2S单斜P21/c结构,450 K以上发生相变成为立方 β-Ag2S相.Ag2S在300～...     

添加剂DTPA对KDP晶体快速生长及性能的影响研究

在添加1×10^-4 (mol/mol KDP) 二乙烯三胺五乙酸(DTPA)的溶液中, 利用“点籽晶”快速生长法生长了KDP晶体. 实验发现, 添加少量DTPA即可使不同饱和温度下的KDP生长溶液的亚稳区宽度均得到提高. 利用激光偏振干涉装置研究了不同浓度的DTPA对KDP晶体(100)面生长动力学的影响. 发现随DTPA掺杂量增加, 临界过饱和度(死区)一直降低, 生长速度则是先增加经过一个最大值后减小. 表征了晶体的光学透过率和晶体内部的杂质金属离子含量, 发现掺杂1×10^-4 (mol/mol) DTPA大幅提高了快速生长的KDP晶体在紫外区的透过率, 并有效地减少了进入晶体内部的杂质金属离子含量.     

溶剂熔区移动法生长Cd0.9Zn0.1Te晶体的工艺优化研

为了解决Cd_0.9Zn_0.1Te(CZT)晶体生长温度高、单晶率低、成分不均匀等问题, 采用溶剂熔区移动法(THM)在优化工艺参数下生长了掺In的CZT晶体, 在优化晶体的生长温度、固液界面处的温度梯度、原位退火过程等生长条件后, 生长出直径为45 mm的低Te夹杂浓度、高电阻率、高透过率、均匀的高质量CZT晶体。 X射线衍射结果显示, 晶体的结晶性较好、Zn成分轴向偏析小。红外透过光谱测试结果显示, 晶体内部的杂质、缺陷水平相对较少, 晶体整体的红外透过率在60%左右。紫外-可见光吸收光谱测试结果也进一步表明, 晶体的均匀性良好。采用红外显微镜对晶体内部的Te夹杂形貌及其尺寸进行观察, 结果表明Te夹杂的尺寸主要分布在0~10 μm之间。采用直流稳态光电导技术测得电子的迁移率寿命积约为8×10^-4 cm²/V。     

Cd补偿垂直布里奇曼法生长Cd0.9Zn0.1Te晶体

采用传统垂直布里奇曼法和Cd补偿垂直布里奇曼法,分别生长出两根尺寸为 30mm×130mm的Ccd0.9Zn0.1Te晶锭.测试了晶体的结晶质量、成分分布、位错腐蚀坑密度(EPD)、红外透过率及电阻率.结果表明,Cd补偿垂直布里奇曼法生长的晶体结晶质量好、成分分布均匀、EPD低、红外透过性能好且电阻率高.这说明Cd补偿垂直布里奇曼法是一种生长高阻值CZT晶体的优良方法.     

退火处理对Y2O3薄膜结构和光学性能的影响

采用射频磁控溅射法以Y2O3陶瓷为靶材在单晶si(Ⅲ)和石英表面制备了Y2O3薄膜.利用X射线衍射(XRD)仪、扫描电子显微镜(SEM)、紫外-可见(UV-VIS)光谱仪和傅立叶变换红外(FTIR)光谱仪对真空退火前后Y2O3薄膜的结构和光学性质进行了分析研究.结构研究表明,在200℃条件下制备的Y2O3薄膜为非晶态,经600℃退火后出现单斜相,经800℃退火后薄膜完全转化为立方多晶,同时得到了不同晶面的晶粒尺寸;沉积态的Y2O3薄膜由球状颗粒排列组成,经800℃真空退火后薄膜为柱状晶.光学性质研究发现,真空退火后Y2O3薄膜的红外透过率显著下降;使用Tauc作图法得到不同结晶条件下的光学带隙,发现薄膜的光学带隙与结晶条件有关,并且退火后薄膜的光学带隙明显减小.     

光子晶体及其应用

主要介绍光子晶体的基本概念,光子晶体的晶体结构和能带结构方面的三种计算方法,并简单介绍光子晶体的应用。     

非化学计量溶液区熔法生长大尺寸InSe晶体及表征（英文）

硒化铟(InSe)是一种具有奇异物理性能的Ⅲ-Ⅵ族半导体材料,在光伏、光学、热电等领域有着广泛的应用潜力。由于InSe的非一致熔融特性及InSe、In₆Se₇和In₄Se₃之间复杂的包晶反应,制备大尺寸In Se晶体十分困难。本研究采用区熔法制备了InSe晶体,该方法具有成本低、固液界面优化等优点。基于In-Se体系的包晶反应,发现In与Se的初始物质的量比对InSe晶体生长非常重要,本工作使用精确非化学计量的In0.52Se0.48溶液生长晶体,使In Se晶体的获得率达到83%左右。实验最终获得了?27 mm×130 mm的晶棒,并成功剥离出尺寸?27 mm×50 mm的片状In Se单晶, XRD图谱中检测到(00l)衍射峰,说明晶体的质量良好。In Se晶体呈现六方结构,各元素在基体中均匀分布,在1800 nm波长下的透射率为～55.1%,带隙能量为～1.22 e V。在800 K下, In Se晶体沿(001)方向的最大电导率σ约为1.55×10² S·m^–...     

悬浮区域熔炼法制备Ce1-xPrxB6单晶体及其热发射性能研究

以CeB₆和PrB₆粉末为原料, 采用放电等离子烧结结合悬浮区域熔炼法成功制备了晶体质量良好的多元稀土六硼化物Ce_1-xPr_xB₆(x=0.1、0.2、0.4)单晶体, 并系统研究了该系列单晶体(100)晶面热电子发射性能。结果表明: Ce_0.8Pr_0.2B₆单晶(100)晶面具有最好的热发射性能, 在1873 K, 最大电流发射密度达到66.07 A/cm², 比CeB₆单晶的电流发射密度提高约20%。此外, Ce_0.9Pr_0.1B₆、Ce_0.6Pr_0.4B₆单晶(100)晶面的热发射电流密度分别为65.81 A/cm²和65.31 A/cm²。Ce_0.8Pr_0.2B₆单晶(100)晶面的逸出功最低, 为2.61 eV, 其它单晶(100)晶面的逸出功在2.64~2.753 eV范围内。因此, Ce_1-xPr_xB₆多元稀土六硼化物单晶具有良好的发射性能和低的逸出功, 作为热阴极材料有很好的应用前景。     

Slow‐Photon‐Effect‐Induced Photoelectrical‐Conversion Efficiency Enhancement for Carbon‐Quantum‐Dot‐Sensitized Inorganic CsPbBr3 Inverse Opal Perovskite Solar Cells

All‐inorganic cesium lead halide perovskite is suggested as a promising candidate for perovskite solar cells due to its prominent thermal stability and comparable light absorption ability. Designing textured perovskite films rather than using planar‐architectural perovskites can indeed optimize the optical and photoelectrical conversion performance of perovskite photovoltaics. Herein, for the first time, this study demonstrates a rational strategy for fabricating carbon quantum dot (CQD‐) sensitized all‐inorganic CsPbBr₃ perovskite inverse opal (IO) films via a template‐assisted, spin‐coating method. CsPbBr₃ IO introduces slow‐photon effect from tunable photonic band gaps, displaying novel optical response property visible to naked eyes, while CQD inlaid among the IO frameworks not only broadens the light absorption range but also improves the charge transfer process. Applied in the perovskite solar cells, compared with planar CsPbBr₃, slow‐photon effect of CsPbBr₃ IO greatly enhances the light utilization, while CQD effectively facilitates the electron–hole extraction and injection process, prolongs the carrier lifetime, jointly contributing to a double‐boosted power conversion efficiency (PCE) of 8.29% and an increased incident photon‐to‐electron conversion efficiency of up to 76.9%. The present strategy on CsPbBr₃ IO to enhance perovskite PCE can be extended to rationally design other novel optoelectronic devices.     

Ultrastable CsPbBr3 Perovskite Quantum Dot and Their Enhanced Amplified Spontaneous Emission by Surface Ligand Modification

The poor stability and aggregation problem of CsPbBr₃ quantum dots (QDs) in air are great challenges for their future practical application. Herein, a simple and effective ligand‐modification strategy is proposed by introducing 2‐hexyldecanoic acid (DA) with two short branched chains to replace oleic acid (OA) with long chains during the synthesis process. These two short branched chains not only maintain their colloidal stability but also contribute to efficient radiative recombination. The calculations show that CsPbBr₃ QDs with DA modification (CsPbBr₃‐DA QDs) have larger binding energy than CsPbBr₃ QDs with OA (CsPbBr₃‐OA QDs), resulting in significantly enhanced stability. Due to the strong binding energy between DA ligands and QDs, CsPbBr₃‐DA QDs exhibit no aggregation phenomenon even after stored in air for more than 70 d, and CsPbBr₃‐DA QDs films can maintain 94.3% of initial PL intensity after 28 d, while in CsPbBr₃‐OA QDs films occurs a rapid degradation of PL intensity. Besides, the enhanced amplified spontaneous emission (ASE) performance of CsPbBr₃‐DA QDs films has been demonstrated under both one‐ and two‐photon laser excitation. The ASE threshold of CsPbBr₃‐DA QDs films is reduced by more than 50% and their ASE photostability is also improved, in comparison to CsPbBr₃‐OA QDs films.     

光学浮区法生长YFeO3晶体

采用光学浮区法生长了新型磁光晶体YFeO3，通过工艺优化，获得了Ф（7-10）mm、长度约60mm的YFeO3晶体、XRD分析表明晶体具有正交钙钛矿结构，晶格常数a=5．5964A，b=7．6052A，c=5．2842A．晶体生长界面为凸界面，生长取向接近[100]方向、晶体截面抛光后观察，未发现肉眼可见的包裹体、晶界等缺陷、     

Morphology-Dependent Charge Carrier Dynamics and Ion Migration Behavior of CsPbBr3 Halide Perovskite Quantum Dot Films

Exceptional electronic, optoelectronic, and sensing properties of inorganic Cs-based perovskites are significantly influenced by the defect chemistry of the material. Although organic halide perovskites that have a polycrystalline structure are heavily studied, understanding of the defect properties at the grain boundaries (GB) of inorganic Cs-based perovskite quantum dots (QDs) is still limited. Here, morphology-dependent charge carrier dynamics of CsPbBr₃ quantum dots at the nanoscale by performing scanning probe microscopy of thermally treated samples are investigated. The grain boundaries of defect-engineered samples show higher surface potential than the grain interiors under light illumination, suggesting an effective role of GBs as charge collection and transport channels. The lower density of crystallographic defects and lower trap density at GBs specifically of heat-treated samples cause insignificant dark current, lower local current hysteresis, and higher photocurrent, than the control samples. It is also shown that the decay rate of surface photovoltage of the heated sample is quicker than the control sample, which implies a considerable impact of ion migration on the relaxation dynamic of photogenerated charge carriers. These findings reveal that the annealing process is an effective strategy to control not only the morphology but also the optoelectrical properties of GB defects, and the dynamic of ion migration. Understanding the origin of photoelectric activity in this material allows for designing and engineering optoelectronic QD devices with enhanced functionality.     

K3C60单晶薄膜制备及表征

根据K在C60 晶体中的扩散系数分析了在C60 (1 1 1 )单晶解理面上制备K3 C60 单晶膜的实验条件。对制备出的样品进行了角分辨光电子谱研究。结果表明样品确实为K3 C60 单晶 ,并首次观察到K3 C60 的能带色散。     

CsPbBr3 Perovskite Nanoparticles causes Colitis-Like Symptom via Promoting Intestinal Barrier Damage and Gut Microbiota Dysbiosis

Lead-based perovskite nanoparticles (Pb-PNPs) with superior optoelectronic properties are promising alternatives for the next generation of photovoltaics materials. This raises a great concern about their potential exposure toxicity in biological systems. However, little is known about their adverse effects on the gastrointestinal tract system so far. Here, the aim is to investigate the biodistribution, biotransformation, potential gastrointestinal tract toxicity, and effect on the gut microbiota after oral exposure to the CsPbBr₃ perovskite nanoparticles (CPB PNPs). The advanced synchrotron radiation based microscopic X-ray fluorescence scanning and X-ray absorption near-edge spectroscopy demonstrate that high doses of CPB (CPB-H) PNPs can gradually transform into different lead-based compounds, subsequently accumulating in the gastrointestinal tract, especially the colon. Meanwhile, the pathological changes of stomach, small intestine, and colon reveal that CPB-H PNPs have higher gastrointestinal tract toxicity than Pb(Ac)₂, consequently leading to colitis-like symptoms. More importantly, 16S rRNA gene sequencing analysis discloses that CPB-H PNPs cause more significant alterations in the richness and diversity of the gut microbiota related to inflammation, intestinal barrier, and immune function than Pb(Ac)₂. The findings may contribute to shedding light on understanding the adverse effects on gastrointestinal tract and gut microbiota of Pb-PNPs.     

Er3+掺杂弛豫铁电材料PMNT的单晶生长与性能表征

按照0.71Pb(Mg_1/3Nb_2/3)O₃-0.26PbTiO₃-0.03Pb(Er_1/2Nb_1/2)O₃化学式所示组分比例, 采用分步高温固相反应合成出Er³⁺掺杂PMNT多晶, 通过熔体坩埚下降法生长出尺寸φ25 mm×100 mm的Er³⁺掺杂PMNT晶体, Er³⁺离子以三元固溶体组元方式被掺杂进入钙钛矿相铁电体晶格; 测试了Er³⁺掺杂PMNT晶片的介电、压电与铁电性能以及上转换发光性能。结果表明, Er³⁺掺杂PMNT晶体呈现跟三方相纯PMNT晶体相近的介电、压电与铁电性能; 在980 nm激发光作用下, 该掺杂晶体呈现出Er³⁺离子特有的较强上转换荧光发射, 并且极化后掺杂晶体的上转换发光强度得到增强。     

半导体ZnO晶体生长及其性能研究进展

ZnO晶体是直接宽带隙半导体材料，室温下禁带宽度为3.37eV，激子束缚能为60meV。其禁带宽度对应紫外光的波长，有望开发蓝绿色、蓝光、紫外光等多种发光器件。对ZnO晶体的生长方法及研究进展做了简要的叙述。