【作者】 李伟；

【导师】 潘春阳；

【作者基本信息】 广东工业大学 ， 化学工程与技术， 2022， 硕士

【摘要】 本文论述了七例不同的新型硼酸盐晶体材料,通过单晶X射线衍射表征了它们的结构,通过固体紫外可见漫反射光谱、红外光谱、X-射线粉末衍分析（PXRD）和元素分析进一步表征了它们的结构。还通过热刻蚀制得了一系列硼酸盐基催化剂,测量了系列催化剂的氧还原反应（ORR）催化活性。化合物Co₂（DMEDA）₃[B₅O₇（OH）₃]₂（DMEDA=N,N-二甲基乙二胺,1）与化合物Zn₂（DMEDA）₃[B₅O₇（OH）₃]₂（2）都是通过溶剂热法合成的。1与2是同构化合物。晶体学参数:单斜晶系,P2₁/c,a=13.1790（5）?,b=16.6760（8）?,c=16.7519（6）?,α=90.00?,β=100.499（2）?,γ=90.00?,Z=4。它们的结构中含有[B₅O₇（OH）₃]^2-硼氧簇和两种配位方式的金属原子,硼氧簇彼此间通过氢键连接。金属配合物桥连硼氧簇,使得结构中具有一维氢键链,一维链与链之间通过氢键连接形成三维开放骨架。2的成功合成说明通过调控晶体结构中的金属阳离子能够合成新型的金属硼酸盐。化合物[Ni（AEEA）][B₅O₆（OH）₄]（AEEA=羟乙基乙二胺,3）和[Ni（atta）（SO₄）_0.5]·[B₅O₆（OH）₄]（atta=N¹,N¹,N²-tris（2-aminoethyl）ethane-1,2-diamine,4）都是通过溶剂热法合成的。3的晶体学参数:单斜晶系,P2₁/c,a=8.4086（4）?,b=11.6933（4）?,c=14.4535（6）?,α=90.00°,β=90.4321（18）°,γ=90.00°,Z=4。4的晶体学参数:单斜晶系,P2₁/c,a=9.0512（2）?,b=15.2776（3）?,c=15.0142（3）?,α=90.00°,β=15.0142（3）°,γ=90.00°,Z=4。两者都是孤立镍硼酸盐,但两者的结构表现出了巨大的差异,3的结构中含有[Ni（AEEA）]⁺金属镍配合物,和[B₅O₆（OH）₄]^-硼五聚阴离子簇,其开放骨架是由丰富的氢键连接而成。而4是一例孤立结构的硫酸硼酸盐,硫酸根单元的引入,使其结构中含有非常特殊的金属氧硫键。两者结构的差异也带了性质的不同。通过紫外光谱分析,3的带隙约为4.75 e V,4的带隙约为4.38 e V,这表明硫酸根单元的引入造成的结构变化使得硼酸盐的带隙减小。同时,通过ORR催化活性测试,3-C系列催化剂的半波电位(E_1/2)为0.78 V,4-C系列催化剂的E_1/2为0.75 V,两者ORR活性的差异归因于结构的差别。化合物Co₂（C₃H₄N₂）₈（SO₄）₂·2H₃BO₃（5）是利用溶剂蒸发法合成的。晶体学参数:三斜晶系,P1,a=9.1985（7）?,b=9.6099（6）?,c=11.5412（7）?,α=76.555（2）°,β=87.681（3）°,γ=82.367（3）°,Z=1。与4类似,它也是一例新型的硫酸硼酸盐,结构中同样含有特殊的金属氧硫键。与4的不同点在于,其结构中的钴配合物通过[SO₄]^2-单元桥连形成了一维杂化链,孤立的硼酸分子通过氢键连接链与链形成三维超分子结构。其带隙约为3.66 e V。测试了其ORR催化活性,5-C系列催化剂最高的E_1/2为0.83 V。通过与4进行比较,发现硼酸盐结构中巨大的孔道结构和空间可以更好的暴露活性位点,进而提高催化活性。化合物[Cu（1-MI）₄]·[B₅O₆（OH）₄]₂·1-MI₂（1-MI=1-甲基咪唑,6）的制备使用的是较为便捷的溶剂蒸发法。晶体学参数:单斜晶系,C2/c,a=15.1658（4）?,b=11.3616（4）?,c=26.8956（11）?,α=90.00°,β=105.0050（10）°,γ=90.00°,Z=4。6是由[Cu（1-MI）₄]²⁺,1-MI和[B₅O₆（OH）₄]^-簇组成的孤立硼酸盐。其带隙约为5.43 e V。通过ORR催化活性测试,6-C系列催化剂表现出的ORR催化活性优于3和4,其最高的E_1/2为0.79 V。在化合物6的实验思路上,使用与6相同的方法成功合成了化合物[Cu（EIM）₄][B₅O₆（OH）₄]₂·3H₂O（7,EIM=1-乙基咪唑）。晶体学数据:三斜晶系,P1,a=9.3010（4）?,b=9.5408（4）?,c=12.6456（6）?,α=106.412（2）°,β=91.722（2）°,γ=104.795（2）°,Z=1。7由金属配合物和[B₅O₆（OH）₄]^-簇组成。其带隙约为3.23 e V。7-C系列催化剂表现出的ORR催化活性比6更好,其最高的E_1/2为0.82 V。对6和7的结构性质进行比较分析表明,引入催化活性更好的金属元素是提高硼酸盐基催化剂催化活性的有效途径。硼酸盐基催化剂的ORR活性还受到样品碳含量、结构的影响。本文详细论述了在温和条件下合成的七例硼酸盐材料。它们表现出了很多有趣的结构与性质,同构化合物1和2证实了金属元素对结构的差异性影响。3,4和5表明往硼酸盐体系中引入阴离子基团是可行的,随着阴离子基团的引入也造成了样品结构和性质的巨大转变。6与7的结构与性质证实了通过选择反应物可以调控硼酸盐的结构和硼酸盐基催化剂的ORR活性。更多还原

【Abstract】 In this thesis,seven different new borate crystalline materials are prepared,their structures are characterized by single crystal X-ray diffraction and further characterized by UV-vis,IR,PXRD and elemental analysis.A series of borate-based catalysts were prepared by thermal etching method,and the catalytic activity of the series of catalysts for oxygen reduction reaction was measured.Co₂（DMEDA）₃[B₅O₇（OH）₃]₂（DMEDA=N,N-Dimethylethylenediamine,1）and Zn₂（DMEDA）₃[B₅O₇（OH）₃]₂（2）were synthesized by solvothermal method.1 and 2 are isostructural compounds.Crystallographic parameters:Monoclinic,P2₁/c,a=13.1790（5）?,b=16.6760（8）?,c=16.7519（6）?,α=90.00?,β=100.499（2）?,γ=90.00?,Z=4.Their structure contains[B₅O₇（OH）₃]^-clusters and cobalt atoms,and the[B₅O₇（OH）₃]^-clusters are connected with each other by hydrogen bonds.The cobalt atoms connect with the boron-oxygen clusters,so that the structure has a one-dimensional chain structure,and then one-dimensional chains are connected by hydrogen bonds to form a three-dimensional open framework structure.The successful synthesis of 2 shows that new metal borates can be synthesized by regulating the metal cations in the crystal structure.We compared the subtle differences with its isomer.[Ni（AEEA）][B₅O₆（OH）₄]（AEEA=2-（2-Aminoethylamino）ethanol,3）and[Ni（atta）（SO₄）_0.5]·[B₅O₆（OH）₄]（atta=N¹,N¹,N²-tris（2-aminoethyl）ethane-1,2-diamine,4）were all synthesized by solvothermal method.Crystallographic parameters of 3:Monoclinic,P2₁/c,a=8.4086（4）?,b=11.6933（4）?,c=14.4535（6）?,α=90.00°,β=90.4321（18）°,γ=90.00°,Z=4.Crystallographic parameters of 4:Monoclinic,P2₁/c,a=9.0512（2）?,b=15.2776（3）?,c=15.0142（3）?,α=90.00°,β=15.0142（3）°,γ=90.00°,Z=4.Both are new nickel borates,but the structures of the two compounds show great differences.The structure of 3 contains[Ni（AEEA）]⁺complex,and[B₅O₆（OH）₄]^-.The introduction of sulfate unit makes its structure containing a very special metal oxygen-sulfur bond.As we knew.it is the first nickel complex sulfate borate that was synthesized under mild conditions.The band gaps E_gof 3 and 4 are about 4.75 e V and 4.28 e V,respectively.This suggests that the structural change caused by the introduction of sulfate groups reduces the band gap of sample.Through the ORR catalytic activity test,3-C series catalysts exhibit the highest half-wave potential(E_1/2)at the potential of 0.78 V,4-C series catalysts exhibit the highest half-wave potential(E_1/2)at the potential of 0.75 V.The difference in catalytic activity of 3and 4 is attributed to their different structures.Co₂（C₃H₄N₂）₈（SO₄）₂·2H₃BO₃（5）was synthesized by solvent evaporation method.Crystallographic parameters:Triclinic,P1,a=9.1985（7）?,b=9.6099（6）?,c=11.5412（7）?,α=76.555（2）°,β=87.681（3）°,γ=82.367（3）°,Z=1.It is the first cobalt complex sulfate borate.The difference from 4 is that the cobalt complex in its structure is bridged by[SO₄]^2-unit to form a one-dimensional chain structure,and the chains are linked with isolated borate molecules through hydrogen bonds to form a three-dimensional supramolecular structure.The value of its band gap is about 3.66 e V.We tested its ORR catalytic activity,5-C series catalysts exhibit the highest E_1/2at the potential of 0.83 V.By comparison with 4,we found that the huge pore structure and space in the structure of borate-based catalysts can better expose the active sites,thereby enhancing their catalytic activity.[Cu（1-MI）₄]·[B₅O₆（OH）₄]₂·1-MI₂（6,1-MI=1-methylimidazole）were synthesized by solvent evaporation method.Crystallographic parameters:Monoclinic,C2/c,a=15.1658（4）?,b=11.3616（4）?,c=26.8956（11）?,α=90.00°,β=105.0050（10）°,γ=90.00°,Z=4.6is an isolated borate composed of[Cu（1-MI）₄]²⁺,1-MI and[B₅O₆（OH）₄]^-clusters.The value of its band gap is about 5.43 e V.The ORR catalytic activity of 6 was better than that of 3 and4.Its highest E_1/2is 0.79 V.Based on the experimental idea of 6,we successfully synthesized the[Cu（EIM）₄][B₅O₆（OH）₄]₂·3H₂O(7,（EIM=1-ethylimidazole）using the same method as6.Crystallographic data:Triclinic,P1,a=9.3010（4）?,b=9.5408（4）?,c=12.6456（6）?,α=106.412（2）°,β=91.722（2）°,γ=104.795（2）°,Z=1.7 consists of metal complexes and[B₅O₆（OH）₄]^-clusters.The value of its band gap is about 3.23 e V.It exhibits better ORR catalytic activity than 6 with the highest E_1/2of 0.82 V.The comparative analysis of the structural properties of 6 and 7 shows that the introduction of metal elements is a feasible method to improve the ORR activity of borate-based catalysts.The ORR activity of borate-based catalysts is also affected by the carbon content and structure of the samples.In this thesis,seven examples of borate materials synthesized under mild conditions.They exhibit many interesting structures and properties.The isostructural 1 and 2 confirmed the differential influence of metal elements on the structure.3,4 and 5 show that it is feasible to introduce anionic groups into the borate system.The introduction of anionic groups also caused a dramatic transformation in the structure and properties of the samples.The structures and properties of 6 and 7 demonstrate that the structure of borate and the ORR activity of borate-based catalysts can be regulated by choice of reactants.更多还原