单一配体与混合配体协同构筑的一系列多酸基化合物:结构、电化学及选择性光催化性能研究

A series of POM-based compounds constructed by mono-and mixed-ligands synergetically:structures,electrochemical and selective photocatalytic properties

通过使用吡嗪(pz)及其衍生物2,3-萘吩基-苯并吡嗪(npz)和2,3-二苯基-苯并吡嗪(dpz),水热合成了1个基于Lindqvist型和6个Keggin型多酸的化合物,该系列化合物由单一配体或混合配体共同修饰多阴离子而构筑:[Ag^I_2(npz)_4(W_6O_(19))]·(npz)(1),[Ag^I_2(npz)_3(HPW_(12)O_(40))](2),[Ag^I_3(npz)_4(PMo_(12)O_(40))](3),[Ag^I_4(pz)_5(SiMo_(12)O_(40))](4),[Ag^I_4(npz)_2(pz)(PMo^VMo_(11)^(VI)O_(40))](5),[Ag^I_4(npz)_4(dpz)_2(SiW_(12)O_(40))(H_2O)_2](6),{Ag^I_5K^I_2(npz)_4(dpz)_2[H(PW^VW_(11)^(VI)O_(40))_2]}(7),并用X射线单晶衍射表征了它们的结构.化合物1中包含一个扭曲的"I"型的[Ag(npz)_2]^+亚单元,其中两个npz相互垂直.两个[Ag(npz)_2]^+亚单元对称的支撑在[W_6O_(19)]^(2-)阴离子上.在化合物2中,由一个二配位连接型和两个单配位终端npz配体构筑[Ag_2(npz)_3]^(2+)簇,该簇由[PW_(12)O_(40)]^(3-)进一步连接形成"日出"型链.化合物3中包含一个孤立的[Ag_2(npz)_3]^(2+)簇和一个单支撑的多阴离子[Ag^I(npz)(HPW_(12)O_(40))]^-.化合物4展示了一个蜂窝状的Ag-pz层,包含两种环路:六元环I和八元环II.多酸阴离子靠Ag连接形成的多酸二聚体,并倾斜嵌入较大的环路II中.在化合物5中,1个pz和2个npz被4个Ag^I连接形成一个直线型的[Ag_4(npz)_2(pz)]^(4+)亚单元.PMo_(12)多阴离子交替连接链状亚单元从而构筑一个一维链结构.化合物6中存在孤立的[Ag_2(npz)_2(dpz)(H_2O)]^(2+)亚单元和多阴离子.化合物7中,Keggin-K无机链被Ag^I-npz-dpz亚单元连接形成一个二维层.相邻层被多阴离子进一步连接构筑三维框架.此外,还研究了该系列多酸基化合物的电化学和光催化性质.

By using pyrazine(pz)and its derivatives 2,3-naphthalenylphenazine(npz)and 2,3-diphenylpyrazine(dpz),one Lindqvist-and six Keggin-based compounds,[AgI2(npz)4(W6O19)]·npz(1),[AgI2(npz)3(HPW12O40)](2),[AgI3(npz)4-(PMo12O40)](3),[AgI4(pz)5(SiMo12O40)](4),[AgI4(npz)2(pz)(PMoVMo11VIO40)](5),[AgI4(npz)4(dpz)2(H2O)2(SiW12O40)](6)and{AgI5KI2(npz)4(dpz)2[H(PWVW11VIO40)2]}(7),have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analyses.In compound 1,there is a distorted'I'-type[Ag(npz)2]+subunit with two npz arranging vertically.Two[Ag(npz)2]+subunits support the[W6O19]2-anion symmetrically.In compound 2,there are[Ag2-(npz)3]2+clusters with one linking and two terminate npz,which are further linked by[PW12O40]3-anions to form a'sunrise'-like chain.In compound 3,there exist a discrete[Ag2(npz)3]2+cluster and a mono-supporting anion[AgI(npz)-(HPW12O40)]-.In compound 4,there are two kinds of cycles in honeycomb-like Ag-pz layer:six-membered cycle I and eight-membered cycle II.An anion dimmer linked by a AgIion embeds in bigger cycle II.In compound 5,one pz and two npz are connected by four AgIions to build a linear[Ag4(npz)2(pz)]4+subunit.The PMo12anions link the linear subunits alternately and a 1D chain is formed.In compound 6,there exists discrete[Ag2(npz)2(dpz)(H2O)]2+subunit and Keggin anion.In compound 7,the Keggin-K inorganic chains are connected by AgI-npz-dpz subunits to form a 2D layer.The adjacent layers are further linked by anions to build a 3D framework.Moreover,we also have investigated the electrochemical and photocatalytic properties of 1–7.