Comparative Study of the Efficacy of Metal Removal from Contaminated Aqueous Solutions by Solid Bidentate Ligands&Liquid Plant Materials

Heavy metal contaminated water sources pose serious health risks for humans,animals,and plants.Exposure to and ingestion of heavy metals have been associated to liver,kidney,and brain function.Objective:The aim of this research is to comparatively examine the metal removal efficacy of three solid bidentate chemicals and four plant materials.Study Design&Methods:Standard solutions of zinc(II)and lead(II)ions with concentrations of 1,000 ppm were respectively treated with OA(Oxalic Acid),dibasic bidentate ligands(sodium hydrogen phosphate and sodium carbonate).Then,the solutions were placed on a shaker for 15 h,centrifuged,and the supernatant was analyzed using ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry).Results:All the solid bidentate adsorbents were very effective in removing zinc and lead(>90%).However,more lead than zinc was removed across all adsorbents except for lemon where equal percent of zinc and lead(49%)were removed.OA and Na2HPO4 removed about equal amount of lead(>99%).The plant materials(SP(Spinach),bell pepper and GBP(Green Bell Pepper)),respectively and preferentially removed more lead(98.9%,98.3%,81.5%)than zinc(91.7%,46%,46%).Conclusion:Although plant materials have gained attraction for the remediation of heavy metal,however,some bidentate chemical ligands such as OA,sodium carbonate and sodium hydrogen phosphates are even more effective in removing these metals from contaminated water.Furthermore,heavier metals are preferentially removed than lighter metals.

Ligand assisted copper-catalyzed Ullmann cross coupling reaction of bromaminic acid with amines

Three types of ligands have been developed for copper-catalyzed Ullmann cross coupling reaction of bromaminic acid with amines in aqueous solution. Ligands with large steric hindrance and strong electron-donating capacity were beneficial to the reaction. UV–Vis and CV analyses demonstrated that these ligands had strong coordination with copper(I), implying the effect of ligand coordination ability on the stability and catalytic activity of catalytic system.

Synthesis and thermal studies of mixed ligand complexes of Cu(II), Co(II), Ni(II) and Cd(II) with mercaptotriazoles and dehydroacetic acid

A series of new mixed ligand complexes of cobalt(II), nickel(II), copper(II) and cadmium(II) have been synthesized with 3benzyl1H4[(2 methoxybenzylidine) amino]1, 2, 4triazole5 thione (MBT), 3bezyl1H4[(4chlorobenzylidine) amino]1, 2, 4triazole5thione (CBT), 3benzyl 1H4[(4nitrobenzylidine)amino]1, 2, 4triazole 5thione (NBT) and dehydroacetic acid sodium salt (Nadha). The mixed ligand complexes have been characterized by elemental analysis, spec troscopic spectral measurements (IR, UVVis.), molar conductance, magnetic measurements and thermal studies. The stoichiometry of these com plexes is M:L1:L2 = 1:1:1, 1:2:1 or 1:1:2 where L1 = NBT, CBT and MBT and L2 = Nadha. Tetrahedral structure was proposed for all Cd(II) mixed ligand complexes while the square planar geometry was proposed for Cu(II) mixed ligand complex with NBT. Octahedral structure was proposed for Ni(II), Co(II) mixed ligand complexes and Cu(II) mixed ligand complexes with CBT and MBT ligands. The thermal decomposition study of the prepared complexes was monitored by TG, DTG and DTA analysis in dynamic nitrogen atmosphere. TG, DTG and DTA studies confirmed the chemical formulations of theses complexes. The kinetic parameters were determined from the the thermal decomposition data using the graphical methods of CoatsRedfern and HorwitzMetzger. Thermodynamic parameters were calculated using standard relations.

Flexible Bis(benzimidazole)-based Ligands Directed the Structure Characteristics of Coordination Polymers Based on Diphenic Acid Co-ligands:Syntheses, Structures and Properties

Two new coordination polymers [Cu_2(bbim)(dpa)_2(C_2H_5OH)_2](1), [Co(dpa)_2(bbbm)](2)(H_2dpa = diphenic acid, bbim = 1,1?-(1,6-hexanediyl)bis-1H-benzimidazole, bbbm = 1,1?-(1,4-butanediyl)bis-1 H-benzimidazole) constructed from bis(benzimidazole)-based ligands with different lengths and diphenic acid co-ligand have been synthesized under solvothermal conditions.Complex 1 possesses Cu-dpa helical chains. The adjacent chains are connected by the bbim ligands into two-dimensional(2D) 3-connected(63) topology. Differently, the layer structure of 2 was consisted by one-dimensional chains containing alternated 8-and 18-membered rings. Furthermore,the thermal stability and fluorescence property for all crystalline materials have been investigated.

Synthesis,Crystal Structure and Antitumor Activity of a Novel Zn(Ⅱ)Complex with 2-(Nicotinoyloxy)acetic Acid Ligand

A novel Zn（Ⅱ） complex, [ZnL2（H2O）4]·H2O（1, HL = 2-（nicotinoyloxy）acetic acid）, was synthesized using Zn（OAc）2·2H2O and 2-（nicotinoyloxy）acetic acid as raw materials. Its structure has been elucidated by elemental analysis, IR and single-crystal X-ray diffraction. The structural analysis revealed that complex 1 crystallizes in triclinic, space group P1 and the Zn（Ⅱ） atom is six-coordinated with two N atoms from two different 2-（nicotinoyloxy）acetate anion ligands and four O atoms from coordinated water molecules. Complex 1 forms a 3D network structure by O–H···O hydrogen bonds. The antitumor activities of 2-（nicotinoyloxy）acetic acid ligand and its Zn（Ⅱ） complex were evaluated against human lung adenocarcinoma A549 cells, human hepatoma SMMC-7721 cells and human colon carcinoma Wi Dr cells.

Enantioselective extraction of mandelic acid enantiomers based on chiral ligand exchange

Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu2+ at different pH values were studied in a water/alcohol two-phase system containing Cu2+ and N-n-（dodecyl-L-proline（A）.） The influences of the solvent sort, the pH value, the concentrations of Cu2+ and chiral ligand on the partition coefficient（K） and separation factor（α） were discussed. The experimental results show that the A formed has more stable ternary complex with D-mandelic acid enantiomer than with L-mandelic acid enantiomer. There is an important influence of the pH value on K and α. When the pH values are less than 3.5, the formation of binary complexes is thermodynamically unfavourable. K and α become maximum when pH values are above 3.5 and the molar ratio of the chiral ligand to Cu2+ is 2∶1.

A Pair of 3D Homochiral Coordination Polymers with Open Channels Constructed by Lactic Acid Derivative Ligands and In-situ Formed Anions

With the help of in-situ formed CH_3COO- anion, a pair of 3D homochiral coordination polymers with open channels were constructed by the assembly of lactic acid derivative ligands, 1.4-DIB ligands and Cd（II） ions, namely [Cd3（（R）-CIA）2（CH3CO2）_2（1.4-DIB）2（H2O）2]·x（Guest）（1-D） and [Cd3（（S）-CIA）2（CH3CO2）2（1.4-DIB）2（H2O）2]·x（Guest）（1-L）. They contain 1D interesting ladder-like Cd-（R）-CIA（3-） chains and exhibit SHG-active behavior and photoluminescent property.

Synthesis of Coordination Polymers Using Different Maleic Acid Ligands under Hydrothermal Conditions

A novel coordination polymer, [ Ni （mal） （1,10＇-phen） （ H2O） ] n （ 1 ） （ mal = malate, 1,10＇-phen = 1,10- phenanthroline） was synthesized using malic acid which was generated from maleic acid via hydrothermal reaction. Complex 1, which displays a two-dimensional supramolecular network, was formed by the addition reaction of Ni and maleic acid with water molecules. To our knowledge, several coordination polymers have been directly synthesized from malic acid, but these types of complexes have seldom been synthesized from maleic acid via hydrothermal reactions. When Ni（ Ⅱ ） ion was changed to Zn（ Ⅱ） ion under the same condition, two-dimensional covalent complex 2 [ Zn2 （fma） 2 （1,10＇-phen） 2 ] n （fma = fumatic acid） was formed. Furthermore, complex 2 exhibits intense photolumi- nescent property at room temperature.

Separation of Neutral Amino Acids with Ligand Exchange Resins

Four neutral amino acids (Gly, Ala,.Val and Leu) were separated with ligand exchange resins. The separation capacity of the ligand exchange resins is compared with that of common ion exchange resins. The effects of eluent, column temperature, and central metal ions of the support on the separation are studied. The relationship between matrix structure of resins and their separation capacity is analysed.

Significance of Ligand Exchange Relating to Sulfate in Retarding Acidification of Variable Charge Soils Caused by Acid Rain

For the purpose of evaluating the role of ligand exchange of sulfate ions in retarding the rate of acidification of variable charge soils, the changes in pH after the addition of different amounts of HNO_3 or H_2SO_4 to representative soils of China were measured. A difrerence between pH changes caused by the two kinds of acids was observed only for variable charge soils and kaolinite, but not for consted charge soils and bentonite. The larger the proportion of H_2SO_4 in the HNO_3-H_2SO_4 mixture, the lower the calculated H￣+ ion activities remained in the suspension. The difference in H￣+ ion activities between H_2SO_4 systems and HNO_3 systems was larger for soils with a low base-saturation (BS) percentage than those with a high BS percentage. The removal of free iron oxides from the soil led to a decrease in the difference, while the coating of Fe_2O_3 ona bentonite resulted in a remarkable appearance of the difference. The effect of ligand exchange on the acidity status of the soil varied with the soil type. SurfaCe soils with a hash organic matter content showed a less pronounced effect of ligand exchange than subsoils did. It was estimated that when acid rain chiefly containing H_2SO_4 was deposited on variable charge soils the acidilication rate might be slower by 20%-40% than that when the acid rain chiefly contained HNO_3 for soils with a high organic matter content, and that the rate might be half of that caused by HNO_3 for soils with a low organic matter content, especially for latosols.

Syntheses of Coordination Compounds of 2-Amino-3-Methylbutanoic Acid Their Mixed Ligand Complexes and Antibacterial Activities

Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However, for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.

Thin-Layer Chromatographic Separation of Amino Acid Enantiomers using Ligand Exchange

Silica gel thin-layer plates covered with L-arginine and copper acetate were used for the separation of amino acid enantiomers, The chromatographic selectivity and the effects of plate different preparation methods, sample molecular structure and solvent compositions on resolution performance were also discussed.

基于对苯二甲酸的MOFs对含氧阴离子的吸附及光降解研究

以对苯二甲酸为配体与金属盐反应得到两个金属-有机框架材料Cd-MOF和UiO-66,通过X射线粉末衍射仪(XRD)、热分析仪(TG)以及氮气吸脱附对两种MOFs材料进行表征,测试材料的纯度、热稳定性以及多孔性。用所合成的材料进行吸附和光催化降解含氧阴离子实验。结果表明:Cd-MOF对MnO^(-)_(4)、Cr_(2)O_(7)^(2-)和CrO_(4)^(2-)的吸附率分别可以达到100%、57%、62%,经过光降解后的去除率可达到100%、84%、87%,UiO-66对MnO^(-)_(4)、Cr_(2)O_(7)^(2-)、CrO_(4)^(2-)的吸附率分别可以达到66%、25%、60%,经过光降解后的去除率可达到99%、40%、87%。相对于吸附能力,两种MOFs材料对含氧阴离子尤其是含Cr阴离子均表现出更好的光催化降解能力,Cd-MOF对含氧阴离子的去除率优于UiO-66。机理研究表明,在光催化降解过程中产生了活性物质·O^(-)_(2)和·OH,它们的产生有助于提高降解效率。

基于Fas/FasL信号通路对桂药生精胶囊治疗少精子症的临床研究

目的探讨桂药生精胶囊对少精子症(肾精亏虚型)患者的精子浓度(SC)、前向运动精子比例(PR)、PR+非前向运动精子比例(NP)、精子总数、精子脂肪酸合成酶(Fas)信使RNA(mRNA)、脂肪酸合成酶配体(FasL)mRNA表达水平及精浆Fas蛋白、FasL蛋白表达水平的影响。方法选取2019年10月至2020年3月就诊于广西中医药大学附属瑞康医院男性科门诊的少精子症(肾精亏虚型)患者60例,随机分为对照组和治疗组,每组30例。对照组采用左卡尼汀治疗,治疗组在对照组的基础上联合桂药生精胶囊治疗,12周为1个疗程。观察治疗前后两组患者的SC、PR、PR+NP、精子总数、精子Fas mRNA、FasL mRNA和精浆Fas蛋白、FasL蛋白表达水平。结果治疗组总有效率比对照组高(P<0.05)。治疗前两组患者SC、PR、PR+NP和精子总数比较,差异均无统计学意义(P>0.05)。治疗后两组患者精子SC、PR、PR+NP和精子总数均比治疗前高(P<0.05),且治疗组患者精子SC、PR和精子总数高于对照组(P<0.05)。治疗前两组患者精浆Fas和FasL蛋白表达水平比较,差异均无统计学意义(P>0.05)。治疗后两组精浆Fas蛋白表达水平低于治疗前(P<0.05),且治疗组Fas蛋白表达水平低于对照组(P<0.05)。治疗前两组患者精子Fas mRNA和FasL mRNA表达水平比较,差异均无统计学意义(P>0.05)。治疗后两组患者精子Fas mRNA和FasL mRNA表达水平低于治疗前(P<0.05),且治疗组Fas mRNA表达水平低于对照组(P<0.05)。结论桂药生精胶囊能明显提高少精子症(肾精亏虚型)患者的SC、PR、精子总数,降低精子Fas mRNA及精浆Fas蛋白的表达水平。

基于Fas/FasL信号通路探索舒芬太尼对急性心肌梗死大鼠心功能和心肌细胞凋亡的影响

目的基于脂肪酸合成酶(Fas)/脂肪酸合成酶配体(FasL)信号通路探索舒芬太尼对急性心肌梗死(AMI)大鼠心功能和心肌细胞凋亡的影响。方法选择健康雄性SD大鼠108只,适应性饲养7天,随机分为对照组、模型组、舒芬太尼低剂量组、舒芬太尼高剂量组、舒芬太尼高剂量+Fas阴性对照组、舒芬太尼高剂量+Fas慢病毒组,每组18只。模型组、舒芬太尼低剂量组、舒芬太尼高剂量组、舒芬太尼高剂量+Fas阴性对照组、舒芬太尼高剂量+Fas慢病毒组通过冠状动脉左前降支结扎法制作AMI模型;对照组除不结扎冠状动脉左前降支外,其余步骤与AMI模型相同。舒芬太尼低剂量组和舒芬太尼高剂量组分别于AMI模型制作成功后腹腔注射0.1、1µg/kg舒芬太尼。舒芬太尼高剂量+Fas阴性对照组和舒芬太尼高剂量+Fas慢病毒组分别于AMI模型制作成功后腹腔注射1µg/kg舒芬太尼,尾静脉注射200 nmol/kg NC shRNA慢病毒或Fas shRNA慢病毒。对照组和模型组腹腔注射等量生理盐水。术后72 h,采集大鼠尾静脉血,采用ELISA法检测血清肌钙蛋白T;采用超声心动图检测左心室射血分数(LVEF)、左心室缩短分数(LVFS)、左心室舒张末期内径(LVEDd)和左心室收缩末期内径(LVESd)。待大鼠心功能检测完成后,腹主动脉取血,采用ELISA法检测血清TNF-α、IL-6。所有大鼠断头处死,留取心脏,随机取6只大鼠的心脏组织,TTC染色,计算心肌梗死面积;随机取6只大鼠的心脏组织,HE染色,观察心肌组织病理形态变化,采用TUNEL法检测细胞凋亡情况;取剩余6只大鼠的心脏组织,采用Western blotting法检测细胞凋亡相关蛋白Bcl-2、Bax、Caspase-3及Fas/FasL信号通路相关蛋白表达。结果与对照组比较,模型组血清肌钙蛋白T水平升高,LVEDd、LVESd升高,LVEF、LVFS降低,血清TNF-α、IL-6水平升高,心肌梗死面积增大,细胞凋亡率及Bax、Caspase-3、Fas、FasL蛋白表达升高,Bcl-2蛋白表达下降(P均<0.05);与对照组比较,模型组心肌细胞形态模糊、纹理消失、排列紊乱、心肌间小血管扩张、细胞数量减少,可见大量炎性细胞浸润。与模型组比较,舒芬太尼低剂量组和舒芬太尼高剂量组血清肌钙蛋白T水平降低,LVEDd、LVESd降低,LVEF、LVFS升高,血清TNF-α、IL-6水平降低,心肌梗死面积减小,细胞凋亡率及Bax、Caspase-3、Fas、FasL蛋白表达降低,Bcl-2蛋白表达升高(P均<0.05);与模型组比较,舒芬太尼低剂量组和舒芬太尼高剂量组心肌细胞形态、纹理、排列、血管扩张、细胞数量及炎性细胞浸润显著改善。以舒芬太尼高剂量组上述效果改善较为明显。与舒芬太尼高剂量+Fas阴性对照组比较,舒芬太尼高剂量+Fas慢病毒组血清肌钙蛋白T水平升高,LVEDd、LVESd升高,LVEF、LVFS降低,血清TNF-α、IL-6水平升高,心肌梗死面积增大,细胞凋亡率及Bax、Caspase-3、Fas、FasL蛋白表达升高,Bcl-2蛋白表达降低(P均<0.05);与舒芬太尼高剂量+Fas阴性对照组比较,舒芬太尼高剂量+Fas慢病毒组心肌细胞形态模糊、纹理消失、排列紊乱、心肌间小血管扩张、细胞数量减少,炎性细胞浸润明显。结论舒芬太尼可改善AMI大鼠心功能,抑制心肌细胞凋亡,并且1µg/kg舒芬太尼的作用效果要优于0.1µg/kg舒芬太尼;抑制Fas/FasL信号通路激活可能是舒芬太尼改善AMI大鼠心功能的作用机制之一。

基于一种唑类羧酸配体的两种配合物的合成、结构及染料吸附性能研究

以1-(3,5-二羧基苄基)-1,2,4-1H-三唑-3-羧酸(H_(3)L1)为有机配体,选择Cu^(2+)和Pb^(2+)为金属中心,通过溶剂热反应制备得到两种新的配合物[Cu(L1)·(CH_(3)CN)_(2)]·H_(2)O(1)和[Pb(L2)](2),H_(2)L_(2)为H_(3)L1原位脱羧产物,并通过单晶X-射线衍射、红外光谱、X-射线粉末衍射、热重分析等对配合物进行表征和分析.染料吸附实验结果表明,配合物1对亚甲基蓝的吸附效率为84.0%,而配合物2对结晶紫的吸附效率为60.2%.

泛癌分析揭示SREK1在低级别胶质瘤中促进CD274表达

目的剪接调节谷氨酸和富赖氨酸的蛋白质1(SREK1)在多种肿瘤中的泛癌分析,揭示SREK1在泛癌中的作用。方法利用在线数据库GEPIA 2、TIMER 2.0、TISIDB和cBioPortal分析SREK1表达对肿瘤患者预后的影响、在低级别胶质瘤(LGG)肿瘤组织中的表达、遗传变异的特征及其表达对肿瘤组织中免疫细胞的浸润和免疫—肿瘤靶基因的相关性分析。结果LGG肿瘤组织中,SREK1表达与记忆B细胞、活化的CD4+T细胞、Th2细胞、中性粒细胞、NKT细胞以及单核细胞和CD56dimNK细胞的浸润存在相关性(P均<0.05)。SREK1与免疫—肿瘤靶基因如信号传导及转录激活蛋白3(STAT3)、Ⅰ型干扰素受体1(IFNAR1)、核受体亚家族3C组成员1(NR3C1)和表皮生长因子受体(EGFR)、表面抗原分化簇274(CD274)等表达在LGG中均呈正相关(P均<0.05)。结论SREK1是LGG患者的危险因子之一,可能通过促进CD274的表达来加剧LGG的进展。

半乳糖上调内皮细胞Siglec-9聚糖配体水平抑制巨噬细胞活性

目的探究半乳糖对人原代肺动脉内皮细胞上唾液酸特异性Ig样凝集素-9(sialic-acid-binding immunoglobulin-like lectin 9,Siglec-9)聚糖配体表达的影响及作用机制。方法采用流式细胞术确定内皮细胞表面Siglec-9聚糖配体的表达并鉴定该聚糖配体末端糖苷键类型;分别用左旋葡萄糖、葡萄糖、N-乙酰基葡萄糖、甘露糖、N-乙酰基甘露糖、半乳糖、唾液酸、蔗糖处理内皮细胞48 h,采用流式细胞术检测内皮细胞Siglec-9聚糖配体的表达;将内皮细胞分为对照组和半乳糖组(n=3),Western blot、流式细胞术、免疫荧光分析半乳糖对内皮细胞Siglec-9聚糖配体表达的影响;α2-3,6,8唾液酸酶处理内皮细胞后,Western blot检测半乳糖对内皮细胞Siglec-9聚糖配体恢复时间的影响;半乳糖处理内皮细胞后,Western blot检测分析细胞内唾液酸合成关键酶(GNE、NANS、NANP、CMAS、NPL以及ST3Gals)表达水平,并用RT-qPCR验证相关蛋白的mRNA表达;siRNA敲低NANP、CMAS及ST3Gal-Ⅲ,Western blot检测内皮细胞Siglec-9聚糖配体水平变化;巨噬细胞与内皮细胞共培养实验分析Siglec-9聚糖配体的增加对巨噬细胞的凋亡与吞噬能力的影响。结果内皮细胞上表达有Siglec-9聚糖配体且该配体为末端结构为α2-3连接的唾液酸糖蛋白;与对照组比较,半乳糖组内皮细胞上该聚糖配体表达水平显著增加(P<0.01),但半乳糖的添加对该配体的自我恢复时间无影响;与对照组比较,半乳糖处理的内皮细胞中NANP、CMAS、ST3Gal-Ⅲ表达水平升高(P<0.05,P<0.01),且RT-qPCR验证结果与其一致;抑制内皮细胞中NANP、CMAS、ST3Gal-Ⅲ的表达后,内皮细胞Siglec-9聚糖配体水平下降(P<0.01)。共培养实验中,与未处理组比较,半乳糖处理的内皮细胞促进巨噬细胞凋亡增加(P<0.01),并导致其吞噬能力减弱(P<0.05)。结论半乳糖通过NANP-CMAS-ST3Gal-Ⅲ通路上调内皮细胞上Siglec-9聚糖配体水平,从而抑制巨噬细胞活性。

羧酸配体金属Co配合物的合成、结构及磁性

羧酸配体配合物在气体吸附/分离、催化、光学和磁学等众多领域均有潜在的应用价值。以5-氨基间苯二甲酸(5-H_(2)AIPC)和吡嗪甲酸(2-HPC) 2种羧酸作为配体,在溶剂热条件下与氯化钴反应,合成2种新型金属钴配合物{[Co_(2)(μ_(3)-OH_(-))_(2)(5-HAIPC)(2-PC)]}_n(1)和{[Co_(2)Cl_(2)(2-PC)_(2)(H_(2)O)_(3)]}_n(2)。通过X-射线单晶衍射、红外光谱和热重分析对配合物1和2的结构进行了表征。X-射线单晶衍射结果表明:配合物1属于C2/c空间群,由椅式四核簇经5-氨基间苯二甲酸和吡嗪甲酸2种配体连接形成三维框架结构。配合物2属于P2_1/c空间群,由配体吡嗪甲酸与金属中心Co2连接形成无限延伸的一维链,配体吡嗪甲酸与Co1连接形成二维层状结构,金属中心Co1和Co2通过配体连接进而通过氢键组装成1个三维超分子结构。对2种配合物的磁性进行测试研究,结果表明:配合物1和2均呈反铁磁性。

新型吡啶甲酸类铱磷光材料的合成、晶体结构及性能

铱磷光材料由于发光效率高、热稳定性好、发光颜色易调控等优点,成为目前综合性能最优异的有机电致发光材料。Ir(C^N)2(L^X)型铱磷光配合物是最为重要的一类铱磷光发光材料,通过调控配体的化学结构,如引入供/吸电子基团、增大共轭程度等来达到改变发光颜色、发射波长和性能等目的。本工作从辅助配体着手,选用N^O型的吡啶甲酸衍生物为辅助配体,通过不同性质的基团对其结构进行调控;分别以3-三氟甲基-2-吡啶甲酸(Tricid)和异喹啉-1-甲酸(Qicid)为辅助配体,以2-(2,4-二氟苯基)-5-甲基吡啶(Medfppy)为主配体,设计合成出两种吡啶甲酸类铱磷光材料Ir1和Ir2。通过核磁共振谱、质谱和单晶X射线衍射等测试手段表征了它们的组成和化学结构,并确定了Ir1和Ir2的晶体结构,Ir1为单斜晶系,P2_(1)/c空间群;Ir2为三斜晶系,P-1空间群,均呈现出稍微扭曲的八面体构型;通过热重分析测试了材料的热稳定性,Ir1和Ir2的热分解温度分别为319℃和364℃;通过紫外-可见光谱和光致发光光谱研究了材料的光物理性能,Ir1和Ir2在二氯甲烷溶液中的最大发射波长分别为582 nm和607 nm;通过循环伏安法测试了材料的电化学性质,并计算得到材料的HOMO-LUMO能级。研究结果表明:与吡啶甲酸(Pic)上引入吸电子基团(-CF_(3))相比,增大共轭程度对铱磷光材料的发射波长作用程度较大;增大共轭程度不仅使配合物的最大发射波长产生了红移,还提高了材料的热稳定性,对设计新型的铱磷光材料具有一定的借鉴意义。