CuxO用于调控全无机碳基CsPbI2Br钙钛矿太阳能电池的界面性能

基于CsPbI₂Br的全无机碳基钙钛矿太阳能电池由于碳电极与钙钛矿层间接触性能较差和能带不匹配等问题,导致其光电转化效率较低。本文采用简单的葡萄糖还原法结合煅烧技术制备了两种不同形貌和结构的规则八面体构型Cu_xO,将之作为无机空穴传输材料,制备了结构为导电玻璃(FTO)/SnO₂/CsPbI₂Br/CuxO/C的碳基钙钛矿太阳能电池,研究了CuO和Cu₂O的形貌、结构对光电性能的影响机制。结果显示：CuO和Cu₂O皆具有良好的化学稳定性和p型载流子传输特性,可有效增强CsPbI₂Br钙钛矿层与碳电极层之间的界面接触,改善载流子传输性能,减少电荷复合,延长光电子寿命。基于Cu₂O和CuO的CsPbI₂Br基碳基钙钛矿太阳能电池(C-PSC)器件的光电转换效率最高分别为11.62%和13.22%,分别比空白对照器件的光电转化效率提高了19.5%和36.0%。此外,通过添加Cu₂     

Ultra-smooth CsPbI_2Br film via programmable crystallization process for high-efficiency inorganic perovskite solar cells

CsPbI₂Br is an ideal inorganic perovskite material with a reasonable bandgap for solar cell applications because of its advantage of superior thermal and phase stability. However, the performance of CsPbI2Br based solar cells highly relied on the perovskite crystallization process along with the interfacial contact engineering process between CsPbI₂Br perovskite and charge-transporting layers. In this work, a programmable crystallization method is developed to obtain ultra-smooth CsPbI₂Br perovskite film with a well-engineered contact interface in perovskite solar cells. This method combines a pre-stand-by process with a programmable gradient thermal engineering process, which mediates the crystal growth dynamics process of CsPbI2Br perovskite by controlling the release of dimethyl sulfoxide(DMSO) from its coordinates with the perovskite film, leading to high-quality CsPbI₂Br film with large-scale crystalline grains, reduced surface roughness, and low trap density. Fabricated perovskite devices based on CsPbI₂Br film obtained by this method deliver power conversion efficiency of 14.55 %;meanwhile, the encapsulated CsPbI₂Br perovskite device achieves a maximum efficiency of 15.07 %. This decent solar conversion efficiency demonstrates the effectiveness of the programmable crystallization method used in this work,which shows great potential as a universal approach in obtaining high-quality CsPbI₂Br perovskite films for fabricating high-efficiency inorganic perovskite solar cells.     

离子色谱法同时测定福州大气PM2.5中无机阴离子和有机酸的研究

本文利用离子色谱法对福州市2015-2016年大气PM_2.5样品中4种无机阴离子(F^-、Cl^-、NO₃^-、SO₄^2-)和5种水溶性有机物(WSOC)(甲酸、乙酸、乙二酸、丁二酸、戊二酸)进行同步测定,结果表明,无机阴离子曲线相关系数大于0.999,有机酸相关系数大于0.994,检出限范围(0.7-25.7)ng/m³,精密度范围(0.3-7.9)%,回收率范围(84.0-116)%,方法性能满足测试要求。SO₄^2-、NO₃^-、Cl^-为主要的水溶性无机阴离子,3种离子浓度之和占PM2.5质量浓度的32.6%。5种水溶性有机酸WSOC的浓度均值范围为(0.031-0.308)μg/m³,总和占PM2.5质量浓度的1.6%,其中乙二酸的含量相对最高。总体而言,PM2.5中水溶性无机离子和有机酸浓度的季节变化表现为春、冬季高,夏、秋季低的特点。NO₃^-、乙二酸在夏季表现出不同的浓度特征可能与物质的性质和夏季高温强辐射天气有关。乙二酸与SO42-、NH4+、NO3-有较强的线性相关性,初步推断其主要来源为光化学反应而形成的二次污染物。     

作为钠硫电池正极的碳约束NiS2纳米结构中钠离子的储运特性

用电弧蒸发法和固相硫化法制备核壳结构的碳约束NiS₂纳米材料(NiS₂@C)。用X射线衍射(XRD)、透射电镜(TEM)和Raman等手段对其表征的结果表明,外部碳层有较多的缺陷,厚度为4 nm,NiS₂的粒径为28 nm。作为Na-S电池正极材料的电化学性能：在电流密度为100 mA·g^-1条件下NiS₂@C正极材料4次循环后库伦效率保持在90%以上,循环500次后仍有106.8 mAh·g^-1的可逆比容量,具有较高的循环稳定性。电化学阻抗分析结果表明,NiS₂@C外部碳层的良好电子导电性和优异的结构稳定性加快了电极反应并维持着界面离子迁移的动力学平衡。     

PDMS低温热解制备有机/无机膜的研究

以聚二甲基硅氧烷(PDMS)为前驱体聚合物, 采用浸渍法在支撑体上涂覆制备PDMS支撑膜, 将其在惰性气氛下350~480℃低温热解, 制备有机/无机膜。考察了制膜工艺条件对膜气体分离性能的影响; 并借助于TG和FT-IR测试手段探讨了PDMS 的热解过程及化学结构的变化; 采用SEM对有机/无机膜的微观形貌进行表征。研究表明, 采用低温热解法可以成功制备出气体分离性能良好的有机/无机膜。该膜既保留了有机膜的柔韧性, 又具有无机膜的热稳定性好的优点, 并表现出良好的气体渗透性能和选择性。PDMS制膜液的浓度、浸渍次数、复合膜的热解温度及基体孔径和性质等因素对有机/无机膜的气体分离性能以及膜层结构有较大的影响。在最佳工艺条件下制备的有机/无机膜其O₂渗透通量为21.2 GPU(1 GPU=7.501×10^-12 m³(STP)/(m²?s?Pa)), O₂/N₂分离系数为2.28。     

(Lu0.5In0.5)2O3:Tm3+,Yb3+超细粉末的合成和上转换发光

先用液相沉淀技术合成Lu/In/Tm/Yb四元体系水合碱式碳酸盐类沉淀前驱体,然后将其在1100℃煅烧制备出一系列类球状平均粒度约为110 nm的[(Lu_0.5In_0.5)_0.999-xTm_0.001Yb_x]₂O₃ (x=0~0.05)氧化物固溶体。在980 nm泵浦激光激励下这种氧化物粉体在可见光区发射出强烈的蓝青光(450~510 nm,源于Tm³⁺离子4f¹²电子组态内¹D₂→³H₆,³F₄电子跃迁)和较弱的红光(650~670 nm,源于Tm³⁺离子的¹G₄→³F₄电子跃迁),二者的上转换过程均为双光子吸收。随着Yb³⁺离子浓度的提高1931CIE色坐标上的发射光颜色逐渐由绿光(0.31, 0.54)移向蓝光(0.01, 0.19)。Yb³⁺离子共掺提高了Tm³⁺离子的上转换发光强度,其最佳含量为2.5%。发射474 nm蓝光和654 nm红光的粉体,其荧光寿命分别约为0.84和0.97 ms。     

Er2O3掺杂Gd2(Zr0.8Ti0.2)2O7陶瓷的物理性能

用固相反应法制备(Gd_1-xEr_x)₂(Zr_0.8Ti_0.2)₂O₇(摩尔分数x=0,0.2,0.4)陶瓷并测试其晶体结构、显微形貌和物理性能,研究了Er₂O₃掺杂的影响。结果表明,(Gd_1-xEr_x)₂(Zr_0.8Ti_0.2)₂O₇陶瓷具有立方烧绿石结构,显微结构致密,在室温至1200℃高温相的稳定性良好;Er³⁺掺杂降低了陶瓷材料的热导率和平均热膨胀系数,当x=0.2时,其1000℃的热导率最低(为1.26 W·m^-1·k^-1)。同时,Er³⁺掺杂还提高了这种材料的硬度和断裂韧性。     

杂化钙钛矿(HOC2H4NH3)2CuCl4的制备与表征

采用低温溶液法合成了新型层状有序的含有羟基的有机/无机杂化钙钛矿材料(HOC₂H₄NH₃)₂CuCl₄, 采用元素分析、红外光谱、紫外-可见光吸收光谱、X射线衍射和X射线吸收精细结构等手段对其结构与性能进行了表征。结果表明:该材料通过无机框架诱导有机组分有序排列, 形成了规则的层状结构, 有序性高。该杂化钙钛矿材料的分解温度为212℃, 电阻率为2.86×10⁶ Ω·cm, 比不含羟基杂化钙钛矿的电阻率低两个数量级。紫外-可见光吸收光谱显示285 nm左右有一归因于电子从Cl(3p)价带顶跃迁到Cu(4s)导带底而产生的吸收峰。X射线吸收精细结构谱图表明: 二维层状杂化钙钛矿晶体中的Cu²⁺与6个Cl^-形成八面体配位, Cu-Cl键长为0.191 nm, 层间距为1.099 nm。     

水蒸气二氧化碳共活化制备聚苯胺基活性碳在离子液体超级电容器中的应用

通过水蒸气二氧化碳(H 2O(gas)-CO₂)共活化的物理活化方法制备聚苯胺基活性碳被广泛应用于商业活性碳的规模化生产,相比于化学活化方法,该方法制备的活化产物无活化剂残留、清洗简单且工艺过程环保。以聚苯胺为原料,探究了H 2O(gas)的量和CO₂分压对活化产物的影响。采用氮气吸/脱附、扫描电镜(SEM)、透射电镜(TEM)等表征手段系统研究了活性碳的孔径分布及孔道结构,采用电化学工作站研究了活性碳作为离子液体电容器电极材料的电化学性能。当H 2O(gas)和碳化产物的质量比为4∶1、CO₂分压为0.6时,所制备活性碳的比表面积和孔体积可分别达到2357 m²·g^-1和1.45 cm 3·g^-1。该样品具有丰富的中孔和大孔结构,且中孔比表面积占总比表面积的比率约为40%。采用离子电解液时,该样品作为电容器的电极材料具有较高的容量,在0.1 A·g^-1的电流密度下容量可达到203 F·g^-1,并拥有优异的倍率性能以及良好的循环稳定性,在10000次循环(5 A·g^-1)后具有91%的容量保持率。采用有机电解液时,其在1 A·g^-1的电流密度下容量可达134 F·g^-1,且在10 A·g^-1的大电流密度下容量保持率达100%。该活性碳在离子电解液和有机电解液中均具有的优异电化学性能,可归因于其丰富的中孔和大孔结构极大地减少了离子迁移阻力,从而提升了其倍率性能和在离子电解液中的循环性能。     

Er3+ 掺杂对Bi3Ti1.5W0.5O9-Bi4Ti3O12 共生无铅压电陶瓷性能的影响

用传统固相法制备了Bi_7-x Er _x Ti_4.5W_0.5O₂₁(BTW-BIT-xEr³⁺,x=0.05、0.10、0.15、0.25、0.35)共生铋层结构无铅压电陶瓷,用BTW-BIT-xEr³⁺的XRD和SEM表征其相结构和形貌,研究了Er³⁺掺杂对其上转换发光性能和电学性能的影响。结果表明：在这种陶瓷中生成了铋层状结构的单一晶相。在980 nm光波激发下所有组分的上转换荧光谱中都能清晰地观察到两个绿光和一个红光发射峰,峰的中心分别位于532 nm、548 nm和660 nm处。改变掺杂Er³⁺离子浓度可调节其强度比。根据BTW-BIT-0.15Er³⁺样品在532 nm和548 nm绿光的光强比拟合了290~440 K的温度灵敏度,结果表明440 K处的灵敏度最大为0.0023 K^-1。Er³⁺离子替代BTW-BIT-xEr³⁺伪钙钛矿层的Bi³⁺使氧空位浓度的降低,降低了高温介电损耗,提高了激活能和压电常数。BTW-BIT-0.15Er³⁺陶瓷的综合电学性能最优,分别为d₃₃=14 pC/N、T_c=697℃,tanδ=0.53%、Q_m=2055。这种陶瓷材料具有最优的发光性能和良好的热稳定性。     

硅元素掺杂改性尖晶石型锰酸锂的研究进展

尖晶石锰酸锂(LiMn₂O₄)具有理论比容量高、热稳定性高、价格低廉、循环性能良好等特点,深受研究者的亲睐,目前已有固相法、燃烧合成法和共沉淀等多种制备方法。为了进一步改善该材料的循环性能,研究者提出了元素掺杂的策略,元素掺杂改性是基于改变材料的晶体结构或材料中部分元素的平均价态来提高材料的电化学性能和结构的稳定性。Si⁴⁺掺杂可以取代材料中的部分Mn⁴⁺,从而使材料产生Jahn-Teller效应的离子数降低和尖晶石锰酸锂的八面体体积扩大,提高电化学性能。为此,综述了近几年来单一硅元素掺杂及硅与其他元素复合掺杂改性尖晶石型锰酸锂正极材料的研究进展。     

L-精氨酸掺杂钙钛矿太阳电池性能研究

钙钛矿太阳电池以其优异的性能和发展潜力而成为新能源领域研究热点, 但仍然存在缺陷密度大、稳定性差等不足。本研究通过实验对比多种常见氨基酸的掺杂效果后, 将小分子有机物L-精氨酸引入钙钛矿前驱体溶液, 并通过二元两步法制备钙钛矿太阳电池。L-精氨酸掺杂提升了器件的光电性能, 光电效率由18.81%提升到21.86%。L-精氨酸通过降低钙钛矿层缺陷密度(由4.83×10¹⁶ cm^-3降低到3.45×10¹⁶ cm^-3), 减少了载流子非辐射复合, 延长了载流子的平均寿命, 且钙钛矿晶粒尺寸增大、晶界减少、薄膜吸光能力增强且稳定性提升, 迟滞效应得到抑制。这是由于L-精氨酸的多种基团与钙钛矿材料作用钝化了缺陷造成的。本研究为钙钛矿太阳电池的性能优化提供了一种借鉴方法。     

Effect of lead on formation and dielectric tunability of (Pbx,Sr1–x)0.85Bi0.1TiO3 thin films

(Pb_x,Sr_{1 x})_0.85Bi_0.1TiO₃ thin films with the perovskite phase structure were prepared on an ITO glass substrate by sol-gel method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and an impedance analyzer were respectively used in order to characterize the phase status, morphology and dielectric properties of the thin films. The results show that during the formation process of (Pb_x, Sr_{1 x})_0.85KBi_0.1TiO₃ thin films, the nucleus of the perovskite phase are initially formed and then congregated. These aggregated nucleus are then transformed as the perovskite-phase crystalline in the thin film. Finally, the crystalline phase grows and separates gradually to form the perfect crystalline-phase structure. The content of the perovskite phase formed in the thin film under rapid thermal process (RTP) is more than that formed under traditional heat treatment with kinetic equilibrium. This is due to the high active decomposed ions that form the perovskite phase directly when heat-treated by RTP. The formation of the perovskite phase therefore overcomes a much lower barrier under RTP than that under traditional calcinations. The structure of the perovskite phase has a close relation to the ratio of Pb/Sr in the system because of the radius difference between Pb²⁺ and Sr²⁺. The transformation temperature between the cubic and the tetragonal structures of the perovskite phase increases with increasing Pb²⁺ content because the radius of Pb²⁺ is larger than that of Sr²⁺. It appears at room temperature when the content of Pb²⁺/Sr²⁺ is about 40/60 in the thin film. Meanwhile, the tetragonality of the perovskite phase is increased when Pb²⁺ ions increase due to its high polarization. The higher tunability of the (Pb_x,Sr_{1 x})_0.85Bi_0.1TiO₃ thin film is exhibited when the film composition is close to the transformation point between the paraelectric and ferroelectric phases. Pb²⁺ions show a dominant factor to affect the Curie point of the system and then changing tunability.     

铯铅卤化物钙钛矿型平面异质结LED的应用与发展

由于优异的光电性能与环境稳定性, 全无机铯铅卤化物CsPbX₃(X=Cl, Br, I)钙钛矿材料自2015年起逐渐成为光电领域的研究热点, 在诸多电子、光电子器件的应用研究中取得了突破性进展, 受到了科学界的广泛关注。本综述结合铯铅卤化物钙钛矿型平面异质结LED的最新研究进展, 对器件的结构及其工作原理进行扼要的介绍, 并着重从提高LED器件发光性能和工作稳定性方面进行优化策略的归类与总结, 最后就稳定高效的无机钙钛矿型平面异质结LED的发展趋势进行了展望。     

Inorganic lead-based halide perovskites: From fundamental properties to photovoltaic applications

Compared with organic–inorganic hybrid halide perovskites (OIHPs), inorganic cesium lead halide perovskites (CsPbX₃) possess superior intrinsic stability for high temperatures and are considered one of the most attractive research hotspots in the perovskite photovoltaic (PV) field in the past several years. The PCE of CsPbX₃ inorganic perovskite solar cells (IPSCs) has increased from 2.9% in 2015 to more than 20% with excellent stability. There are still many on-going studies on the properties of perovskite materials and their applications in PV technology, thereby needing a thorough understanding. Here, the progress of inorganic perovskites is systematically introduced, including the fundamental properties of CsPbX₃ materials and CsPbX₃-based PV devices. The origins of stability and instability of CsPbX₃ and defects in CsPbX₃ are discussed. CsPbI₃-, CsPbI₂Br-, CsPbIBr₂- and CsPbBr₃-based PV devices and performance are comprehensively reviewed. The stabilization methods and mechanism for the photoactive phases of inorganic perovskites with low bandgap are emphasized. Reported strategies to boost the performance of CsPbX₃-based IPSCs are summarized. In the end, the potential of inorganic perovskites is evaluated, which opens up new prospects for the commercialization of IPSCs.     

用于白光LED稀土Eu掺杂SiAlON基荧光粉的发光性能

SiAlON基荧光粉因其优异的化学和物理稳定性,成为近年来发光领域的一个研究热点,尤其在LED等领域,受到研究者的热切关注。稀土掺杂SiAlON基荧光粉体有望成为新一代照明光源。由于缺乏青色光发射,往往会造成显色性能不足。本研究通过传统高温固相法合成了β-Si₅AlON₇:Eu荧光粉,采用X射线衍射仪(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)等研究了其结构、形貌、元素和价态。通过光谱仪表征了样品的激发光谱以及发射光谱的波长范围并测试了热猝灭性能,发现激发波长覆盖紫外至蓝色光区域,并且发射光谱显示出典型的Eu²⁺跃迁的宽谱。在300℃下,样品的发射光强度依然可达到室温强度的40%左右,热激活活化能(E_a)达到了3.7 eV,相比较商用YAG:Ce³⁺(YAG)荧光粉,热稳定性有一定的提升。在与蓝色芯片复合后成功制备了高显色(显色指数R_a=87)的白色发光LED,对应的色温也达到了暖白光范围(CCT=4501K)。本研究实现了SiAlON基青色...     

Review on Recent Progress of All‐Inorganic Metal Halide Perovskites and Solar Cells

All‐inorganic perovskites are considered to be one of the most appealing research hotspots in the field of perovskite photovoltaics in the past 3 years due to their superior thermal stability compared to their organic–inorganic hybrid counterparts. The power‐conversion efficiency has reached 17.06% and the number of important publications is ever increasing. Here, the progress of inorganic perovskites is systematically highlighted, covering materials design, preparation of high‐quality perovskite films, and avoidance of phase instabilities. Inorganic perovskites, nanocrystals, quantum dots, and lead‐free compounds are discussed and the corresponding device performances are reviewed, which have been realized on both rigid and flexible substrates. Methods for stabilization of the cubic phase of low‐bandgap inorganic perovskites are emphasized, which is a prerequisite for highly efficient and stable solar cells. In addition, energy loss mechanisms both in the bulk of the perovskite and at the interfaces of perovskite and charge selective layers are unraveled. Reported approaches to reduce these charge‐carrier recombination losses are summarized and complemented by methods proposed from our side. Finally, the potential of inorganic perovskites as stable absorbers is assessed, which opens up new perspectives toward the commercialization of inorganic perovskite solar cells.     

醋酸铅添加剂在印刷钙钛矿太阳能电池中的应用

印刷钙钛矿太阳能电池采用无机介孔骨架包覆有机无机杂化钙钛矿材料的器件结构,制备工艺简单,原材料成本低廉,且稳定性优异.然而,在介孔骨架中均匀沉积高质量的钙钛矿材料存在一定困难.本研究通过在典型钙钛矿材料甲胺铅碘(MAPbI3)前驱液中引入醋酸铅(Pb(Ac)2)作为添加剂,加快钙钛矿晶体的成核从而改善其在介孔骨架中的生...     

高红外遮蔽SiZrOC纳米纤维膜的制备及其性能研究

陶瓷纤维具有较好的力学、耐高温和抗热震性能,是重要的高温隔热材料.目前,传统陶瓷纤维膜高温隔热性能不佳,限制了其在高温隔热领域的应用.本研究采用静电纺丝技术制备了具有高红外遮蔽性能的SiZrOC纳米纤维膜,纤维的平均直径为(511±108)nm,组成为SiO2、ZrO2、SiOC和自由碳.SiZrOC纤维膜展现出优异的...