巴拉刈在黏粒修飾電極對鄰苯二酚電化學分析上的影響

The Effect of Paraquat on Electrochemical Behavior of Catechol at Clay Modified Electrodes

曾綉丹(Hsiu-Dan Zen) ； 陳鴻基(Horng-Ji Chen) ； 曾志明(Jyh-Myng Zen)

《台灣農學會報》 13卷6期 (2012/12) Pp. 595-617

https://doi.org/10.6730/JAAT.201212_13(6).0005

摘要

苯二酚是土壤腐植物質先驅物中很重要的成分，在影響土壤形成、理化和生物性質與土壤肥力上扮演非常重要的角色。以六種黏土礦物修飾電極對有、無巴拉刈存在時對鄰苯二酚進行電化學分析。試驗結果指出六種黏粒修飾電極偵測鄰苯二酚有兩個還原波電流量（ipc1, ipc2）及兩個氧化波電流量（ipa1, ipa2），其中以鄰羥基苯酮氧化成鄰苯的波電流量（ipa2）較大，且以高嶺石和坡縷石修飾電極偵測到的波電流量較高，高嶺石和坡縷石在六種黏土礦物中具有較多邊緣的-OH官能基。當有巴拉刈存在時，六種黏粒修飾電極對鄰苯二酚所偵測之還原波電流量（ipc1）明顯低於無巴拉刈時，其中尤以同屬於2：1型膨脹性黏土礦物的水輝石、鈉蒙特石與多鐵蒙特石修飾電極所偵測到之ipc1降低的情形較為明顯。此外，六種黏粒修飾電極在有巴拉刈時偵測到之ipa2（31.5～54.2μA）均比無巴拉刈時之ipa2（53.0～72.7μA）低，顯示當巴拉刈的氧化還原反應有助於黏土礦物催化鄰苯二酚之聚合。巴拉刈對不同黏土礦物在鄰苯二酚的電化學催化氧化還原反應上的影響也不同。

關鍵字

黏土礦物 ； 鄰苯二酚 ； 電化學分析

並列摘要

Benzenediol is an important precursor of soil humus and plays a significant role in soil pedogenesis, the physical, chemical and biological properties of soil and soil fertility. We studied the electrochemical behavior of catechol at six clay-modified electrodes in the absence/ presence of paraquat. The results indicated the presence of two reduction peaks (ipc1, ipc2) and two oxidation peaks (ipa1, ipa2) of catechol at the six clay-modified electrodes with larger ipa2 from o-hydroxyphenylketone to o-benzoquinone. Higher ipa2 were detected at the kaolinite and palygorskite modified electrodes among six clay-modified electrodes due to more of edge -OH group. Paraquat significantly decreased the ipc1 of catechol especially at hectorite, montmorillonite and ferruginous smectite of 2: 1 swelling clay minerals. The effects of paraquat on electrocatalytic polymerization of catechol are different for different clay minerals. Nonetheless, clay minerals were proved to promote the electrocatalytic polymerization of catechol through the redox reaction of paraquat.

並列關鍵字

Clay minerals ； Catechol ； Electrochemical behavior