Formation of photo- and thermo-stable layered double hydroxide films with photo-responsive wettability by intercalation of functionalized azobenzenes

Fabrication and properties of Acid Yellow 49 dye-intercalated layered double hydroxides film on an alumina-coated aluminum substrate

“…The CIE 1976 L*a*b* is a color scale based on the Opponent-Colors theory, among L*, a* and b* values indicate the level of lightedark, redegreen and yellowe blue colors [33,34]. Unlike the XRD pattern of powdered ZnAleNO 3 eLDHs which always show strong [00l] reflections, the [00l] reflections of the ZnAleNO 3 eLDH film precursor are relatively weak, which indicates that the LDH platelet crystallites mainly grew on the surface of aluminum with their c axis parallel to the substrate [28]. After reaction with PPDB, the diffraction peaks of the ZnAleNO 3 eLDH film precursor at 10.06 and 20.18 (2q) disappears and two new diffraction peaks appears below 10 , suggesting that PPDB anions have been incorporated into the galleries of the ZnAleLDH with an expansion of d-spacing from 0.88 nm to 2.51 nm because of the much larger size of PPDB than that of NO 3 À anion.…”

“…Substrates such as metal sheets [16,17], metal alloys [18,19], porous anodic alumina/ aluminum [20], glass [21], sulfonated polystyrene [22], boehmitecoated materials [23] and Al 2 O 3 -coated materials [24] have been utilized to prepare LDH films by this method, which have the good mechanical strength and high adhesion to the substrate. The LDH films have been employed as heterogeneous catalysts [25], anticorrosion coatings for metals [18], adsorbents [23], modified electrodes [26], components in optical or magnetic devices [27,28], and sensors [29]. However, there still remains a need for new functional LDH films.…”

Recent Advances in Stimuli‐Responsive Photofunctional Materials Based on Accommodation of Chromophore into Layered Double Hydroxide Nanogallery

“…For example, Chen et al [42] have fabricated a hybrid film with a fluorine-containing azobenzene within the LDH on a porous anodic alumina/aluminum substrate. Irradiation with UV light led to a switch in wettability of the film from superhydrophobic to hydrophilic as shown in Figure 8, and this process could be reversed by subsequent irradiation with visible light.…”

Superhydrophobic Surfaces by Electrochemical Processes

“…Zhang et al used AAO substrates to form layered double hydroxides (LDH) such as NiAl‐LDH–CO 3 2− and ZnAl‐LDH–NO 3 − by simple immersion process 45–47. For example, for the elaboration of ZnAl‐LDH–NO 3 − , the AAO substrates were placed in solutions containing Zn(NO 3 ) 2 , NH 4 NO 3 and NH 4 OH.…”