CAJ | 학술논문

以1,2,4,5-均苯四羧酸(btec)和二-吡啶-(3,2-d:2,3′-f)-二氮萘(Dpq)为混合配体,水热合成了一种三维超分子配合物:[Co_2(Dpq)_2(btec)(H_2O)_6]·2H_2O, 并通过元素分析、红外光谱、热重分析和X射线衍射测试技术对其结构进行了表征. 晶体结构解析结果表明,该配合物属单斜晶系,P2_1/c 空间群,晶胞参数为:a=0.897 8(5) nm,b=2.982 2(16) nm,c=0.705 8(4) nm,β=94.199(6)°,V=1.884 8(18) nm~3,Z= 2,R_1=0.035 0,wR_2=0.079 6. 该化合物由1,2,4,5-均苯四羧酸中羧基氧原子、二-吡啶-(3,2-d:2,3′-f)-二氮萘的螯合氮原子及水分子中氧原子与中心Co(Ⅱ)离子配位,形成六配位的扭曲八面体几何构型. 羧酸作为桥连配体连接2个相邻的中心Co(Ⅱ)离子形成钴配合物的双核单元,双核单元之间通过氢键及π-π堆积作用相互连接构成三维超分子网状结构. 电化学实验结果表明,钴配合物修饰碳糊电极(Co-CPE)在0.1 mol/L乙酸-乙酸钠缓冲溶液中电位范围+600～-300 mV内有1对归属于Co(Ⅱ)/Co(Ⅲ)的氧化还原峰,而且此修饰电极对亚硝酸根的氧化有很好的电催化效果.
이1,2,4,5-균분사최산(btec)화이-필정-(3,2-d:2,3′-f)-이담내(Dpq)위혼합배체,수열합성료일충삼유초분자배합물:[Co_2(Dpq)_2(btec)(H_2O)_6]·2H_2O, 병통과원소분석、홍외광보、열중분석화X사선연사측시기술대기결구진행료표정. 정체결구해석결과표명,해배합물속단사정계,P2_1/c 공간군,정포삼수위:a=0.897 8(5) nm,b=2.982 2(16) nm,c=0.705 8(4) nm,β=94.199(6)°,V=1.884 8(18) nm~3,Z= 2,R_1=0.035 0,wR_2=0.079 6. 해화합물유1,2,4,5-균분사최산중최기양원자、이-필정-(3,2-d:2,3′-f)-이담내적오합담원자급수분자중양원자여중심Co(Ⅱ)리자배위,형성륙배위적뉴곡팔면체궤하구형. 최산작위교련배체련접2개상린적중심Co(Ⅱ)리자형성고배합물적쌍핵단원,쌍핵단원지간통과경건급π-π퇴적작용상호련접구성삼유초분자망상결구. 전화학실험결과표명,고배합물수식탄호전겁(Co-CPE)재0.1 mol/L을산-을산납완충용액중전위범위+600～-300 mV내유1대귀속우Co(Ⅱ)/Co(Ⅲ)적양화환원봉,이차차수식전겁대아초산근적양화유흔호적전최화효과.
A new 3D supramolecular compound, [Co_2(Dpq)_2(btec)(H_2O)_6]·2H_2O, was obtained from the hydrothermal reaction of cobalt(Ⅱ) nitrate with mixed ligands [1,2,4,5-benzenetetracarboxylate(btec) and dipyrido[3,2-d:2′,3′-f]quinoxaline(Dpq)], and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. The results reveal that the compound belongs to the monoclinic system with P2_1/c space group. The cell parameters are a=0.897 8(5) nm, b=2.982 2(16) nm, c=0.705 8(4) nm, β=94.199(6)°, V=1.884 8(18) nm~3, Z=2, R_1=0.035 0, wR_2=0.079 6. The Co(Ⅱ) is coordinated with two nitrogen atoms of one Dpq molecule, one oxygen atom from the bridging ligand btec, and three oxygen atoms from coordinated water molecules, respectively, rendering a six-coordinate mode in a distorted octahedron geometry. Two adjaceut Co(Ⅱ) ions are linked by the bridging ligand btec to construct a dinuclear unit. The 3D supramolecular network of the title compound is formed through hydrogen bonds and π-π stacking interactions. Moreover, the electrochemical properties of carbon paste electrode modified by the compound(Co-CPE) were studied, and the results indicate that the Co-CPE exhibited one-electron redox wave in potential range of 600 to -300 mV due to the metal cobalt ion redox Co(Ⅱ)/Co(Ⅲ). The Co-CPE has good electrocatalytic activity toward the oxidation of nitrite in a 0.1 mol/L HAc-NaAc solution.