TeCl4溶解在鹼性室溫融鹽中藉由滴定及光譜分析是以TeCl62 -型態存在,而由循環伏安圖結果顯示,TeCl62-於-0.68V 經四個電子還原至Te元素,並在-1.1V進一步還原成Te(-II ).此外,Te(IV)會與Te(-II)反應生成碲固體,因而造成 循環伏安圖的改變.利用電位階升法探討Te(IV)與Te(-II) 在碳素電極上還原為Te(0)之成核現象,結果發現Te(IV)至 Te(0)為動力控制,而Te(-II)至Te(0)屬於三度空間逐 步成核.TlCl3溶解在鹼性室溫融鹽中是以TlCl63-形式存在 ,其電化學行為是先在獲得兩個電子還原成Tl(I)之後,再經一個電 子反應還原至元素態Tl.而Tl(I)是以TlCl43-方式存在. 利用電位階升法討論Tl(I)在鎢電極與鎳電極上還原之成核現象,結 果發現皆屬於三度空間瞬時成核. The electrochemistry of Te(IV)an d Tl(I)chloride in basic molten salts was investigated at a glas sy carbon and tungsten electrode at 30oC.Absorption spectroscopy and titration experiments sugge st that tellurium(IV)chloride is complexed as TeCl62- in theseme lts.TeCl62- can be reduced to el emental tellurium via a four ele ctron process.The nucleation pro cess for the electrodeposition o f Te from reduction of TeCl62- e xhibits characteristics indicati ve of kinetic control.Elemental Te can be further reducedto a Te (-II)species which undergoes a r eaction with Te(IV) to form Te.E lemental Te can also via 3D prog ressive nucleation with diffusio n controlled growth.Tl(I)underwe nt a quasi-reversible two-electr on oxidation process to produce Tl(III),and a one-electron reduc tion process to produce metal th allium.Titration experiments sug gest that thallium(III) chloride is complexed as TlCl63- in thes e melts.The formalredox potentia l obertained from Nernst plots i s dependent upon the pCl of the melt,indicating the loss of chlo ride ion from the coordination s phere of the complexe anion duri ng reduction to from a species o f the type TlCl43-.The nucleatio n process for theelectrodepositi on of Tl from reduction of TlCl4 3- exibits characteristics indic ative of instantaneous nucleatio n.
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