Anion exchange in Zn-Al layered double hydroxides: In situ X-ray diffraction study

作者：Salak Andrei N^*; Tedim Joao; Kuznetsova Alena I; Zheludkevich Mikhail L; Ferreira Mario G S

来源：Chemical Physics Letters, 2010, 495(1-3): 73-76.

DOI：10.1016/j.cplett.2010.06.041

Anion exchange capacity is a key factor for the application of Zn-Al layered double hydroxides (LDHs) as nano-containers in active corrosion protection. In this work, the nitrate-pyrovanadate anion exchange/re-exchange processes in these LDHs were investigated in situ. We demonstrate that the exchange reactions lead to a decrease of the average crystallite size of LDHs as a result of mechanical fragmentation of the crystallites rather than dissolution/recrystallization. The fragmentation occurs due to fast anion exchange in the initial stage, and can be controlled by changing the ratio of the available substituent anions to the replacement anions and application of a mechanical activation.

• 出版日期2010-7-29