Surface charging of layered double hydroxides during dynamic interactions of anions at the interfaces

CORC > 生态环境研究中心 > 中国科学院生态环境研究中心 > 环境纳米材料实验室

	Surface charging of layered double hydroxides during dynamic interactions of anions at the interfaces
	Xu, Zhi Ping ; Jin, Yonggang ; Liu, Shaomin ; Hao, Zheng Ping ; Lu, Gao Qing (Max)
刊名	JOURNAL OF COLLOID AND INTERFACE SCIENCE
	2008-10-15
卷号	326 期号:2 页码:522-529
关键词	layered double hydroxide zeta potential surface charging anion adsorption and exchange point of zero charge agglomeration
英文摘要	In this research, we investigated the effect of dynamic anion adsorption/exchange on the surface charging property Of Mg2Al-Cl-LDH and Mg2Al-CO3-LDH particles that show the average zeta potential of 41 and 34 mV in the as-prepared suspension, respectively. The addition of NaCl up to 3 x 10(-3) M in the suspension does not obviously affect the zeta potential of both LDHs, which can be attributed to the less affinity of Cl- to LDH. The introduction of Na2CO3 severely reduces the zeta potential at the CO32- concentration higher than 1 x 10(-4) M, and to the negative value in both LDH systems at ca. 2 x 10(-3) M, which is presumably resulted from the exchange and the re-orientation of CO32- in a tilt/vertical style on the surface. All four organic anions (dodecyl sulfate, folate, citrate and polyacrylate) also significantly affect the zeta potential of the LDH particles. At the lower concentrations of organic anionic groups (<1 x 10(-4) M), the zeta potential was slightly affected, i.e. limited exchange/adsorption. However, the concentration increasing to some point suddenly decreases and reverses the zeta potential of the LDH Particles, which is presumably caused by the hydrophobic interactions that bind the hydrophobic hydrocarbon chains (especially in dodecyl sulfate) into the micelle-like bilayer bunches on the LDH Surface. in addition, the effect of pH in 5.5-11.0 on the LDH particle surface charging is mainly reflected through the conversion of CO32- to HCO3-/H2CO3 when pH decreases from ca. 11 to 6, with limited contribution from protonation/depprotonation and exchange/adsorption. (C) 2008 Elsevier Inc. All rights reserved.
WOS记录号	WOS:000259243600033
内容类型	期刊论文
源URL	[http://ir.rcees.ac.cn/handle/311016/22011]
专题	生态环境研究中心_环境纳米材料实验室
推荐引用方式 GB/T 7714	Xu, Zhi Ping,Jin, Yonggang,Liu, Shaomin,et al. Surface charging of layered double hydroxides during dynamic interactions of anions at the interfaces[J]. JOURNAL OF COLLOID AND INTERFACE SCIENCE,2008,326(2):522-529.
APA	Xu, Zhi Ping,Jin, Yonggang,Liu, Shaomin,Hao, Zheng Ping,&Lu, Gao Qing .(2008).Surface charging of layered double hydroxides during dynamic interactions of anions at the interfaces.JOURNAL OF COLLOID AND INTERFACE SCIENCE,326(2),522-529.
MLA	Xu, Zhi Ping,et al."Surface charging of layered double hydroxides during dynamic interactions of anions at the interfaces".JOURNAL OF COLLOID AND INTERFACE SCIENCE 326.2(2008):522-529.