TY - JOUR
T1 - Synthesis and photochemical properties of zinc-aluminum layered double hydroxide/organic UV ray absorbing molecule/silica nanocomposites
AU - He, Q.
AU - Yin, S.
AU - Sato, T.
N1 - Funding Information:
This work was partly supported by the JSPS Postdoctoral Fellowship for Foreign Researchers in Japan (ID No. P00312) and by Ministry of Education, Culture, Sports, Science and Technology of Japan, a Grant-in-Aid for the COE project, Giant Molecules and Complex Systems.
PY - 2004/2
Y1 - 2004/2
N2 - Organic ultraviolet (UV) ray absorbents have been used as sunscreen materials, but may pose a safety problem when used at high concentration. In order to prevent direct contact of organic UV ray absorbent to the human skin several organic UV absorbents such as 4-hydroxy-3-methoxybenzoic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 4-hydroxy-3-methoxycinnamic acid, 4,4′-diaminostilbene-2,2′-disulfonic acid, p-aminobenzoic acid and urocanic acid were intercalated into Zn2Al layered double hydroxides (Zn2Al-LDHs) by anion-exchange and/or co-precipitation reaction. Thereafter, the obtained nanocomposites were coated with amorphous silica. Significant amounts (20-40mass%) of organic UV absorbers were intercalated as univalent and/or divalent anions. The UV ray absorption ability of the organic UV absorbents increased and their catalytic activity for the air oxidation of castor oil greatly decreased when they were intercalated into the interlayer spaces of the Zn2Al-LDHs. The deintercalation of organic molecules from LDHs by the anion exchange reaction with carbonate ion could be greatly depressed by coating the nanocomposite powder with amorphous silica.
AB - Organic ultraviolet (UV) ray absorbents have been used as sunscreen materials, but may pose a safety problem when used at high concentration. In order to prevent direct contact of organic UV ray absorbent to the human skin several organic UV absorbents such as 4-hydroxy-3-methoxybenzoic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 4-hydroxy-3-methoxycinnamic acid, 4,4′-diaminostilbene-2,2′-disulfonic acid, p-aminobenzoic acid and urocanic acid were intercalated into Zn2Al layered double hydroxides (Zn2Al-LDHs) by anion-exchange and/or co-precipitation reaction. Thereafter, the obtained nanocomposites were coated with amorphous silica. Significant amounts (20-40mass%) of organic UV absorbers were intercalated as univalent and/or divalent anions. The UV ray absorption ability of the organic UV absorbents increased and their catalytic activity for the air oxidation of castor oil greatly decreased when they were intercalated into the interlayer spaces of the Zn2Al-LDHs. The deintercalation of organic molecules from LDHs by the anion exchange reaction with carbonate ion could be greatly depressed by coating the nanocomposite powder with amorphous silica.
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U2 - 10.1016/j.jpcs.2003.08.031
DO - 10.1016/j.jpcs.2003.08.031
M3 - Article
AN - SCOPUS:0942267889
VL - 65
SP - 395
EP - 402
JO - Journal of Physics and Chemistry of Solids
JF - Journal of Physics and Chemistry of Solids
SN - 0022-3697
IS - 2-3
ER -