动态热风辅助再结晶策略改善CsPbI_(2)Br钙钛矿在大气环境下的结晶及其光电性能

CsPbI_(2)Br薄膜在大气环境下制备存在覆盖率低、结晶质量差和结构稳定性差等问题.本文提出了一种动态热风辅助再结晶策略(dynamic hot-air assisted recrystallization,DHR),在相对湿度大于60%(>60%RH)的大气环境下,制备出高覆盖率、(100)择优取向、大尺寸晶粒、结构稳定、光电性能好的CsPbI_(2)Br薄膜.这是由于动态热风过程能够有效提高薄膜的覆盖率和获得(100)择优取向的结晶,但晶粒尺寸会显著减小(R_(ave)=0.32μm)并伴随着大量的晶界形成,从而加剧载流子的非辐射复合(τ_(ave)=99 ns);而通过再结晶过程,可进一步提高(100)择优取向的结晶和显著增大晶粒尺寸(R_(ave)=2.63μm),从而提高薄膜的光致发光强度和荧光寿命(τ_(ave)=118 ns).由DHR策略制备的未封装CsPbI_(2)Br太阳能电池具备高光电转换效率(power conversion efficiency,PCE=17.55%)、低迟滞因子(hysteresis index,HI=2.34%)和长期的储存稳定性(air,>60%RH,40天,初始PCE的96%)等特性.

Crystallization management of CsPbI_(2)Br perovskites by PbAc_(2)-incorporated twice spin-coating process for efficient and stable CsPbI_(2)Br perovskite solar cells

CsPbI_(2)Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase structure.However,the presence of bromine leads to a rapid crystallization rate of CsPbI_(2)Br films,resulting in small grain size and high defect density.Additionally,CsPbI_(2)Br demonstrates poor light absorption due to its wide bandgap.Therefore,it is crucial to control the crystallization rate and increase the film thickness to reduce defect density,enhance light absorption,and improve photovoltaic performance.In this study,we utilized a PbAc_(2)-incorporated twice spincoating(PTS) process to address these issues.Initially,PbAc_(2) was added to the CsPbI_(2)Br precursor solution to form a CsPbI_(2)Br film,which was then coated with the CsPbI_(2)Br precursor solution to produce the PTS film,Ac^(-)can delay the perovskite crystallization,leading to the formation of thicker and denser CsPbI_(2)Br films.Moreover,lone-pair electrons of the oxygen atom provided by Ac^(-)formed coordination bonds with under-coordinated Pb~(2+) ions to fill halogen ion vacancies,thereby reducing the defect density.Ultimately,the PTS CsPbI_(2)Br device achieved a peak power conversion efficiency(PCE) of 16.19% and maintained 96.7% of its initial PCE over 1500 h at room temperature under 25% relative humidity without any encapsulation.

In^(3+)掺杂显著提高碳基CsPbI_(2)Br钙钛矿太阳能电池性能

碳基全无机CsPbI_(2)Br钙钛矿太阳能电池具有成本低、器件结构简单、稳定性好等优点,是一种很有前景的光伏电池。然而,其能量转换效率仍然过低,主要原因在于难以获得质量良好的CsPbI_(2)Br薄膜。为了获得质量良好的CsPbI_(2)Br薄膜,通过在CsPbI_(2)Br钙钛矿前驱体溶液中添加InI_(3),将In^(3+)掺杂到CsPbI_(2)Br晶体结构中以改善钙钛矿薄膜的质量。利用SEM和XRD对钙钛矿薄膜的微观形貌及晶体结构进行表征分析,并系统地测试了器件的光伏性能,包括开路电压、短路电流密度、填充因子、能量转换效率、外量子效率和积分电流密度。结果表明:In^(3+)掺杂可调控CsPbI_(2)Br晶体的生长,通过提高其结晶性获得了致密、无孔洞的高质量钙钛矿薄膜;同时,通过调控InI_(3)的添加量,优化了In^(3+)掺杂的比例,当InI_(3)添加量(质量分数)为0.5%时CsPbI_(2)Br钙钛矿太阳能电池的光伏性能提高更为显著,其器件能量转换效率从7.59%提高至11.16%,开路电压从1.04 V提高至1.22 V。

在UV/H_(2)O_(2)去除对乙酰氨基酚工艺中Br^(-)的影响及其转化规律

Br^(-)是水和废水中常见的卤素离子,在高级氧化过程(advanced oxidation processes, AOPs)中通过形成不同种类的Br相关物种来发挥多种作用。在Br^(-)存在条件下,采用对乙酰氨基酚(acetaminophen, AAP)模拟废水进行UV/H_(2)O_(2)对其降解效能、机理以及Br^(-)转化规律的研究。结果表明,UV/H_(2)O_(2)降解AAP过程中,最佳去除率达到99.1%,但Br^(-)的加入抑制了AAP的降解和矿化,O~·_(2)和OH~·是UV/H_(2)O_(2)降解含Br^(-)的AAP模拟废水中主要活性物质,贡献率分别为45.5%和34.0%。当Br^(-)存在时,中性条件下,AAP降解速率最快,其一级动力学常数为0.048 4 min~(-1);其中活性溴物种(reactive bromide species, RBSs)对AAP降解的贡献率为14.1%。自由基浓度模拟结果表明,Br^(·-)_(2)可能在有机溴的形成过程中发挥着重要的作用。H_(2)O_(2)的直接还原作用导致Br^(-)转化率仅为18.0%。此外,由于溴自由基的加成,容易生成一些具有生态毒性的副产物,并通过分析溴代产物推测了AAP的降解路径。

Modification of compact TiO_(2) layer by TiCl_(4)-TiCl_(3) mixture treatment and construction of high-efficiency carbon-based CsPbI_(2)Br perovskite solar cells

In the construction of high performance planar perovskite solar cells(PSCs),the modification of compact TiO_(2) layer and engineering of perovskite/TiO_(2) interfaces are essential for efficient electron transfer and retarded charge recombination loss.In this work,a facile and effective strategy is developed to modify the surface of compact TiO_(2) layer by TiCl_(4)-TiCl_(3) mixture treatment.Compared with conventional sole TiCl_(4),the TiCl_(4)-TiCl_(3) treatment takes the advantage of accelerated and controlled hydrolysis of TiCl_(3),therefore TiO_(2) with dominating anatase phase and moderate roughness is obtained to facilitate the growth of CsPbI_(2) Br perovskite layer with high quality.Furthermore,the oxidation-driven hydrolysis of TiCl_(3) component results in surface Cl doping that facilitates interfacial electron transfer with retarded recombination loss.The average power conversion efficiency(PCE) of carbon-based CsPbI_(2) Br planar PSCs based on TiCl_(4)-TiCl_(3) treatment increases to 14.18% from the intial 13.04% based on conventional sole TiCl_(4) treatment.The champion PSC exhibits a PCE of 14.46%(V_(oc)=1.28 V,J_(sc)=14.21 mA/cm^(2),and FF=0.794),which is one of the highest PCEs for carbon-based CsPbI_(2) Br PSCs.

Gadolinium-incorporated CsPbI_(2)Br for boosting efficiency and long-term stability of all-inorganic perovskite solar cells

All-inorganic CsPbI_(2)Br perovskite solar cells(PSCs)have received extensive research interests recently.Nevertheless,their low efficiency and poor long-term stability are still obstacles for further commercial application.Herein,we demonstrate that high efficiency and exceptional long-term stability are realized by incorporating gadolinium(III)chloride(GdCl_(3))into the CsPbI_(2)Br perovskite film.The incorporation of GdCl_(3) enhances the Goldschmidt tolerance factor of CsPbI_(2)Br perovskite,yielding a dense perovskite film with small grains,thus the a-phase CsPbI_(2)Br is remarkably stabilized.Additionally,it is found that the GdCl_(3)-incorporated perovskite film achieves suppressed charge recombination and appropriate energy level alignment compared with the pristine CsPbI_(2)Br film.The noticeable increment in efficiency from14.01%(control PSC)to 16.24%is achieved for GdCl_(3)-incorporated PSC.Moreover,the nonencapsulated GdCl_(3)-incorporated PSC exhibits excellent environmental and thermal stability,remaining over 91%or90%of the original efficiency after 1200 h aging at 40%relative humidity or 480 h heating at 85℃ in nitrogen glove box respectively.The encapsulated GdCl_(3)-incorporated PSC presents an improved operational stability with over 88%of initial efficiency under maximum power point(MPP)tracking at 45℃ for1000 h.This work presents an effective ion-incorporation approach for boosting efficiency and long-term stability of all-inorganic PSCs.

Secondary crystallization strategy for highly efficient inorganic CsPbI_(2)Br perovskite solar cells with efficiency approaching 17%

Inorganic CsPbI_(2) Br perovskite solar cells(PSCs) have a tremendous development in last few years due to the trade-off between the excellent optoelectronic properties and the relatively outstanding stability.Herein,we demonstrated a strategy of secondary crystallization(SC) for CsPbI_(2) Br film in a facile planar n-i-p structure(ITO/ZnO-SnO_(2)/CsPbI_(2) Br/Spiro-OMeTAD/Ag) at low-temperature(150℃).It is achieved through the method of post-treatment with guanidinium bromine(GABr) atop annealed CsPbI_(2) Br film.It was found that the secondary crystallization by GABr can not only regulate the crystal growth and passivate defects,but also serve as a charge collection center to effectively collect photogenerated carriers.In addition,due to the excess Br ions in GABr,the formation of the Br-rich region at the CsPbI_(2) Br perovskite surface can further lower the Fermi level,leading to more beneficial band alignment between the perovskite and the hole transport layer(HTL),while the phase stability was also improved.As a result,the champion cell shows a superb open-circuit voltage(V_(oc)) of 1.31 V,a satisfactory power conversion efficiency(PCE) of 16.97% and outstanding stabilities.As far as we know,this should be one of the highest PCEs reported among all-inorganic CsPbI_(2) Br based PSCs.

多肽BR0336在小鼠2型糖尿病合并非酒精性脂肪性肝炎模型上的初步药效学研究

目的研究多肽BR0336注射液在STZ-HFD诱导的雄性C57BL/6小鼠2型糖尿病(T2DM)合并非酒精性脂肪性肝炎(NASH)模型上的药效学。方法新生雄性小鼠通过链脲佐菌素诱导建立T2DM模型,从1个月龄起开始给予高脂饲料喂养,根据空腹血糖和体重随机分为模型组、替西帕肽(TZP)的0.15 mg·kg^(-1)阳性对照组和BR0336的低(0.05 mg·kg^(-1))、中(0.15 mg·kg^(-1))、高(0.5 mg·kg^(-1))剂量组,通过与正常对照组比较,考察小鼠体重、摄食量、空腹血糖、血清胰岛素、糖化血红蛋白、肝功能和血脂情况,并进行肝脏组织病理学NAS和纤维化分析。结果BR0336各剂量组能显著降低模型小鼠的体重、摄食量、空腹血糖、胰岛素和HbA1c%,减低肝脏NAS评分和纤维化率,并对模型动物的肝功能和血脂异常具有良好保护作用。与阳性对照组相比,等剂量BR0336在动物的摄食量、胰岛素、肝功能和血脂生化方面表现更优,能更有效延缓NASH和纤维化进程。结论BR0336对STZ-HFD诱导的T2DM合并NASH模型小鼠在高血糖和脂质代谢紊乱方面具有一定治疗作用。

无铅双钙钛矿Cs_(2)NaScX_(6)(X=Cl,Br,I)的第一性原理研究

钙钛矿材料由于具有结构稳定、易于获取、成本低廉和易于合成等优点,在发光二极管、激光器和太阳能电池等光电器件领域具有广阔的应用前景。目前,部分适合UV-LED应用的钙钛矿具有结构不稳定性。为了寻找结构稳定的钙钛矿,此项研究利用第一性原理对无铅双钙钛矿Cs_(2)NaScX_(6)(X=Cl,Br,I)的电子及光学性质进行了理论计算。计算结果表明:Cs_(2)NaScX_(6)(X=Cl,Br,I)为直接带隙半导体,带隙值分别为5.545 e V(Cl)、4.549 eV(Br)和3.408 eV(I),Cs_(2)NaScI_(6)在紫外光范围内具有较强的光吸收。本研究内容为无铅A_(2)B^(I)B^(III)X_(6)型双钙钛矿成为UV-LED的候选材料提供理论支持。

Enhancing performance of low-temperature processed CsPbI2Br all-inorganic perovskite solar cells using polyethylene oxide-modified TiO_(2)

CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs.

空气中制备碳基无空穴传输层CsPbI_(2)Br钙钛矿太阳能电池研究

基于无机CsPbI_(2)Br的碳基无空穴传输层钙钛矿太阳能电池(carbon based hole transport material freeperovskite solar cells,C-PSCs)具有成本低、易制备和稳定性好等优点而受到广泛关注。研究了空气环境下制备高效稳定的平面异质结CsPbI_(2)Br C-PSCs的2种制备工艺。首先,通过对反溶剂材料的种类及用量、钙钛矿前驱体溶液浓度等参数的优化,在反溶剂为800μL、钙钛矿前驱体溶液浓度为1.2 mol/L的条件下,采用一步溶液法成功制备了光电转换效率为9.87%的CsPbI_(2)Br C-PSCs。其次,为摆脱一步溶液法对有毒反溶剂的依赖,引入低温预退火工艺,通过对预退火时间及温度、钙钛矿前驱体溶液浓度等参数的优化,在空气环境下,预退火温度为80℃、钙钛矿前驱体溶液浓度为1.6 mol/L且未使用反溶剂的条件下获得了10.52%的最佳光电转化效率,同时CsPbI_(2)Br钙钛矿的退火温度可降低至240℃,并且未封装的器件在空气环境下显示出了较好的稳定性。

Double Side Interfacial Optimization for Low-Temperature Stable CsPbI_(2)Br Perovskite Solar Cells with High Efficiency Beyond 16%

CsPbI_(2)Br perovskite solar cells have achieved rapid development owing to their exceptional optoelectronic properties and relatively outstanding stability.However,open-circuit voltage(Voc)loss caused by band mismatch and charge recombination between perovskite and charge transporting layer is one of the crucial obstacles to further improve the device performance.Here,we proposed a bilayer electron transport layer ZnO(bottom)/SnO_(2)(top)to reduce the Voc loss(Eloss)and promote device Voc by ZnO insert layer thickness modulation,which could improve the efficiency of charge carrier extraction/transfer and suppress the charge carrier recombination.In addition,guanidinium iodide top surface treatment is used to further reduce the trap density,stabilize the perovskite film and align the energy levels,which promotes the fill factor,short-circuit current density(Jsc),and stability of the device.As a result,the champion cell of double-side optimized CsPbI_(2)Br perovskite solar cells exhibits an extraordinary efficiency of 16.25%with the best Voc as high as 1.27 V and excellent thermal and storage stability.

溶剂调控法制备碳基全无机CsPbI_(2)Br钙钛矿太阳能电池

通过调控N,N-二甲基甲酰胺(DMF)和二甲基亚砜(DMSO)的配比,制备了碳基全无机CsPbI_(2)Br钙钛矿太阳能电池。采用扫描电子显微镜、X射线衍射仪、紫外可见光谱仪、荧光光谱仪、太阳能I-V测试系统对制备的CsPbI_(2)Br薄膜的结晶形貌、吸光范围和器件性能进行了研究。结果表明:当V(DMF)∶V(DMSO)=8∶2时,混合溶剂的挥发性与配位强度达到了较优的平衡,旋涂过程中由溶剂蒸发诱导的结晶成核速率适中,在退火过程中进行晶体生长,制备的CsPbI_(2)Br薄膜致密无针孔,晶粒尺寸较大,紫外可见光谱吸收范围较广,荧光强度较高,器件效率较优。

C_(12)-2-E_n-C(12)·2Br与SDS混合水溶液的胶团化研究

与[C_(12)H_(25)N^+(CH_3)_2CH_2]_2·2Br^-(简记为 C_(12)-2-C_(12)·2Br)/C_(12)H_(25)SO_4Na(SDS)混合水溶液相比，随着联接链上乙氧基团(E)数目增加，[C_(12)H_(25)N^+(CH_3)_2]_2C_2H_4(OC_2H_4)_n·2Br^-(简记为 C_(12)-2-E_n-C_(12)·2Br，n=2，3)与 SDS 混合水溶液澄清区域明显增大，C_(12)-2-E_3-C_(12)·2Br/SDS 混合胶团化过程中二组分产生了协同效应，理论预测在澄清区域所能达到的最小临界胶团总浓度(cmc_(T.mim))=0.0339mmol·L^(-1)，对应的 SDS 在溶液体相中的摩尔分数(x_2^(*))=0.447．当水溶液体相中 SDS 摩尔分数(x_2)=0.5时，混合胶团总聚集数(N_T)=36，混合胶团中 SDS 的摩尔分数(x_2~M)=0.43。

季铵盐二聚表面活性剂C_(12)-S_2-C_(12)·2Br复配体系在氯仿中形成反胶团的增溶水状态

采用近红外光谱技术,研究了季铵盐Gemini表面活性剂C12-S2-C12.2Br/氯仿体系中反胶团的增溶水状态,使用Peakfit解峰技术,将水的近红外光谱分为3个亚带,分别对应分散于溶剂中的水、反胶团中的类似本体水和结合水。将以上3种状态的水换算成每个表面活性剂分子对应的各种状态水分子数,即分散在溶剂中的水ns、类似本体水nf和结合水nb。向C12-S2-C12.2Br/氯仿体系中加入不同头基的离子型表面活性剂十二烷基三甲(乙)基溴化铵(DTAB、DTEB),发现随着添加剂摩尔分数αA的增大,ns和nb增大,nf减小。加入非离子表面活性剂聚乙二醇辛基苯基醚(OP-10),随着αA的增大ns减小,nb增大,nf略有增大趋势。可见加入表面活性剂头基的大小、所带电荷以及亲水性等均会对反胶团的增溶水能力和状态产生影响。

玉米br-2矮生基因利用的研究

本研究在国内外多年研究的基础上,利用玉米br-2基因的致矮特性,根据基因重组的原理,通过各种杂交方式和选择,使抗病、抗倒、窄叶片等许多优良基因与br-2基因很好地结合,克服了原br-2基因型矮生自交系节间短、叶宽重叠密集、雌雄不协调、授粉不良等一系列缺点,育成了一批具有应用价值的优良矮生系和冀单20号等矮生杂交种,在单基因矮生特性运用于玉米育种研究上取得了进展.

钒-2-(3,5-二溴-2-吡啶偶氮)-5-二乙氨基酚-二苯胍-NaBrO_3体系极谱催化波的研究

本文报道了钒-3,5-Br_2-PADAP-DPG-NaBrO_3新极谱催化波体系,确定了测定钒的适宜底液条件,测定钒的线性范围为0.04～18ng/ml,探讨了极谱波性质,本法成功地应用于自来水和矿样中钒的测定。

隐性单基因br-2玉米矮生系的选育

【目的】研究单基因br-2玉米矮源导入热带血缘选育矮生玉米自交系的效果。【方法】利用玉米br-2基因的致矮特性,根据基因重组的原理,通过导入热带血缘进行回交选择。【结果】选育出配合力高的单基因br-2矮生系南381、南387,组配的玉米杂交种南玉8号和隆单9号先后通过四川省审定,正在中国南方大面积推广应用。【结论】利用隐性矮生基因导入热带血缘,使抗病、抗倒、窄叶片等优良基因与br-2基因良好结合,克服了矮生自交系节间短、叶宽重叠密集、授粉不良等缺点,在玉米育种研究上具有一定的应用前景。

有机反离子对C_(12)-s-C_(12)·2Br水溶液表面活性的影响

溶液中添加的苯磺酸钠(SNzS)和萘磺酸钠(SNphS)与C12-s-C12·2Br产生强烈结合,增大了Gemini表面活性剂分子的疏水性,明显促进其在气/液界面的吸附和在溶液中的聚集.这使得体系降低水表面张力的效率和能力大大提高,并且在表面活性剂浓度很低时就生成了小聚集体.因而,此时表面张力法测得的cmc仅具有表观上的意义,只反映了表面活性剂在气/液界面达到饱和吸附时的临界浓度.SNphS的疏水性强于SNzS,更有效地促进了C12-s-C12·2Br的吸附和聚集.

负载[APMIm][Br]离子液体吸收CO_2的性能

1-氨丙基-3-甲基咪唑溴盐（[APMIm][Br]）离子液体通过化学反应捕集CO2。采用浸渍-蒸发将[APMIm][Br]离子液体负载在硅胶表面，通过比表面孔隙吸附测定仪、热重分析仪（TGA）对吸收剂的结构与性能进行研究，负载量为10%～50%，温度为303.15～323.15 K，CO2浓度分别为10%、30%、50%。结果表明：硅胶表面的离子液体薄膜厚度达到86 nm（负载40%）时，具有最快的吸收速率，且受CO2浓度和温度变化的影响较小，平衡吸收量在50% CO2体系中达到理论吸收量的80%，随着温度的升高而降低，当负载量为50%时，膜厚增加到230 nm，导致吸收速率和平衡吸收量大幅度下降。值得注意的是：负载离子液体吸收剂在循环使用3次之后，结构与性能均保持不变，表现出一定的工业运用前景。