(中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083)
摘 要: 采用超聲耦合隔膜電積技術(shù)從氯鹽體系(Sn(Ⅱ)-Cl--H2O)中電積錫，通過循環(huán)伏安法、線性掃描伏安法、計時電流法及計時電位法，對比研究有無超聲耦合條件下錫隔膜電積的電化學(xué)機理。循環(huán)伏安曲線及線性掃描曲線分析表明，超聲耦合可使錫隔膜電沉積的控制步驟由無超聲耦合時的擴散控制轉(zhuǎn)變?yōu)橛谐曬詈蠒r的電化學(xué)控制；超聲耦合條件下提高溫度、酸度及超聲功率有利于錫的電積；計時電流測試表明，超聲耦合錫隔膜電積初始過程遵循擴散控制的三維成核和晶粒長大機制，超聲波在此過程起到細化晶粒及加快反應(yīng)進程的作用。超聲耦合后，錫的沉積由高擇優(yōu)取向(易產(chǎn)生錫“晶須”)逐漸趨于無擇優(yōu)取向，陰極錫傾向于生成規(guī)則的網(wǎng)狀結(jié)構(gòu)，錫“晶須”得到遏制。同等條件下超聲耦合更有利于獲得結(jié)構(gòu)更致密、形貌更平整的陰極錫。
關(guān)鍵字: 超聲波；隔膜電積；氯鹽體系；電化學(xué)機理
（School of Metallurgy and Environmental, Central South University, Changsha 410083, China）
Abstract:Tin was electrodeposited from chloride solutions by using a membrane cell in ultrasonic field. Cyclic voltammetry(CV), linear sweep voltammetry(LSV), chronoamperometry (CHR) and chronopotentiometry were applied to investigate the electrochemical mechanism of tin electrodeposition under ultrasonic field. Cyclic voltammetry and linear sweep voltammetry diagrams analysis shows that the application of ultrasound can change the tin membrane electro-deposition reaction from diffusion control to electrochemical control, and the increasing of temperature, acidity and ultrasonic power is beneficial to tin electrodeposition. Chronoamperometry curves show that the initial process of tin electrodeposition follows the diffusion controlled three-dimensional nucleation and grain growth mechanism. The coupling ultrasonic field plays a role in refining the grain and accelerating the electro-deposition reaction in this process, and the high preferential orientation of tin (tin whisker) tends to be no preferred orientation. The tin deposition tends to form regular network structure, and the tin whisker can be restrained. The ultrasonic coupling is more favorable to obtain the more compact and more smooth cathode tin under the same condition.
Key words: ultrasonic; membrane electrodeposition; acid chloride electrolyte; electrochemical mechanism
