Intercalation Of Kaolinite Research Articles

Application of modified kaolinite in improving thermal stability of polydimethylsiloxane

AbstractThis research investigated the chemical structure and morphology of the hydrogenated tallow amine (HTA)‐intercalated kaolinite by XRD, FT‐IR, and TEM measurements. The experimental outcomes show that intercalation of kaolinite by HTA, with an intercalation rate of 63.2%, expands the interlayer distance with a subsequent dominant basal XRD peak at 2θ ≈ 7.9°. Furthermore, a composite was created from the HTA‐intercalated kaolinite and polydimethylsiloxane (PDMS) through a favorable interaction between the end silanol groups of PDMS and the modified kaolinite surface. Thermogravimetry‐differential scanning calorimetry results indicate that introducing the HTA‐intercalated kaolinite into the PDMS matrix increases the thermal stability of the composite from 178 to 343 °C. However, the thermal stability of the composite is lower than that of other published materials. The synthesis of kaolinite/PDMS composite with enhanced structural and thermal stability outcomes has been provided via a simple and effective solution method that should have further applications.

Role of Impurities in Kaolinite Intercalation and Subsequent Formation of Nanoscrolls.

Kaolinite (Kaol)-methanol (MeOH) compounds (Kaol-Me) are widely used as the starting materials for further intercalation. The conventional approach to prepare Kaol-Me compounds is to wash dimethyl sulfoxide (DMSO)-intercalated Kaol (Kaol-DMSO) for 16 days, and MeOH must be refreshed every day. Herein, we report a new and much more efficient method to prepare Kaol-Me from Kaol-DMSO by the promotion of AlCl3 under mild conditions, and the corresponding mechanism is investigated. The X-ray diffraction (XRD), Fourier transform infrared spectroscopy, and X-ray fluorescence characterization results reveal that the electric double layer resulting from the impurities absorbed on the kaolinite surface prevents weakly polar molecules from entering the kaolinite interlayers, which is probably the key reason that MeOH must be refreshed daily in the preparation of Kaol-Me compounds. After being treated with HCl to remove the impurities, Kaol-Me-HCl was successfully intercalated by cetyltrimethyl ammonium bromide and subsequently predominantly curled into nanoscrolls.

Effect of original crystal size of kaolinite on the formation of intercalation compounds of coal-measure kaolinite

Coarse crystalline (14.8–19.8 µm) and crypto crystalline (0.51–0.92 µm) coal-measure kaolinite were selected to explore the effect of original crystal sizes on intercalation. Characterization methods of SEM, XRF, XRD, FT-IR, and TG-DTG were utilized to study the original crystal size distribution, chemical composition, crystal structure changes, vibrational characteristics of functional groups, and thermal stability before and after intercalation. The test results reflected that the original crystal size significantly affects the formation of intercalated compounds. Coal-measure kaolinite intercalation compounds have been successfully prepared. Nonlinear fitting curves between the different characterization methods and the original average crystal size showed a significant positive correlation. The results showed that the intercalation effect of coarse crystalline was more significant than those of crypto crystalline, that is to say, the larger the original crystal sizes of coal-measure kaolinite, the higher the intercalation rate, the higher the grafting rate and the more pronounced the mass loss rate. Based on the theory of surface energy and surface charge of mineral particles, the electrical double layer theory which was different from the previous researchers was proposed to explain the intrinsic mechanism of the effect of original crystal size on intercalation.

On the Unusual Temperature Dependence of Kaolinite Intercalation Capacity for N-methylformamide

Many kaolinites are known to exhibit limited intercalation capacity which affects their usage. Some reports have linked this lack of reactivity to particular structural features or to slow kinetics; others recommended increasing intercalation temperature as a remedy. The purpose of the current study was to investigate systematically the N-methylformamide (NMF) intercalation capacity of three kaolinites differing in layer stacking order (KGa-1b, KGa-2, and Imerys Hywite Alum) in the 5–150°C temperature range. Near-infrared spectroscopy (NIR) was employed to record the full kinetics of intercalation in closed systems with excess NMF. Increasing intercalation temperature accelerated the reaction, but the NMF uptake decreased and eventually vanished. Complementary thermogravimetric analysis (TGA) confirmed this unexpected trend. All kaolinites exhibited the same behavior, but the amount of inert material was in the order of their stacking-fault concentration at all temperatures: KGa-2 > Hywite > KGa-1b. Subjecting the samples to stepwise temperature changes showed that, once intercalated, the NMF could not deintercalate and was removed from equilibrium with the surrounding fluid. Thus, intercalation capacity was not a unique feature of the material because it depended on thermal history. As stacking order and thermal history had no detectable effect on the NMF-hosting environment, the unusual temperature dependence was attributed tentatively to the adverse effect of temperature on the adsorption of NMF on the edges of the crystallites, which is a prerequisite for intercalation.

Development of carbon-coated aluminosilicate nanolayers composite shape-stabilized phase change materials with enhanced photo-thermal conversion and thermal storage

Latent heat thermal energy storage (LHTES) system that centers on organic phase change materials (PCM) is regarded as an efficient strategy for the utilization of solar energy. The leakage problem and insensitivity to the sunlight of organic PCM significantly limit the large-scale application in the solar energy storage field. In the current study, a composite shape-stabilized phase change material (ss-PCM) for solar energy utilization was fabricated by incorporating stearic acid (SA) into the carbon-coated aluminosilicate nanolayers developed through intercalation of kaolinite with potassium acetate and then calcination. The resulting composite ss-PCM without leakage possesses excellent encapsulation ability (63.8%) and high latent enthalpy (132.0 J/g), which are ascribed to the higher specific surface area and pore volume of the carbon-coated aluminosilicate nanolayers, and good compatibility. The photo-thermal conversion efficiency of the final composite ss-PCM is up to 92.1%. After 500 heating-cooling cycles, the number of thermal cycles does not show an apparent effect on the enthalpy of the composite ss-PCM, implying its outstanding thermal cycle stability. The mechanism of leakage proof and photo-thermal conversion performance enhancement of composite ss-PCM were explored. The leakproof ability of composite ss-PCM is not only related to the solid capillary force and surface tension of carbon-coated aluminosilicate nanolayers but also the strong chemical bond between SA molecules and these nanolayers. The carbon layers of the supporting material provide an excellent light absorption property. Hence, this work may offer a new idea for designing and constructing the clay mineral (kaolinite) with a special nanolayer structure for preparing composite ss-PCM with superior photo-thermal conversion and solar energy storage capacity.

The preparation of high-yield uniform nanotubes from coal-measure kaolinite

A clean and efficient method was used to prepare kaolinite nanotubes from coal-measure kaolinite. Dimethyl sulfoxide, methanol, and cetyltrimethylammonium chloride were used to prepare intercalation compounds. We characterized the structures, surface functional group changes, morphology, and intercalation rates by x-ray diffraction (XRD), fourier transform infrared spectrometer (FT-IR), scanning electron microscopy (SEM), and transmission electron microscope (TEM). The intercalation rates of intercalation compounds of CK-D, CK-M, and CK-CTAC obtained from the x-ray diffraction (XRD) patterns reach 96.62%, 89.05%, and 86.96%, respectively. The morphology of the intercalation compounds of CK-D and CK-M did not change significantly before and after intercalation, showing a flaky accumulation similar to the original coal-measure kaolinite. Meanwhile, the macromolecular structure of the cetyltrimethylammonium chloride agent had a significant effect on the morphological changes of the kaolinite intercalation compounds. It can directly increase the basal spacing of coal-measure kaolinite from 7.15 Å to 38.38 Å, which is 5.36 times the original basal spacing. The energy input of the ultrasonic instrument can accelerate and enhance the exfoliation process of nanotube formation.

Efficient preparation of coal-series kaolinite intercalation compounds via a catalytic method and their reinforcement for styrene butadiene rubber composite

A series of coal-series kaolinite intercalation compounds were efficiently prepared via a catalytic method. The efficiently prepared intercalation samples were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The intercalation ratio (IR) of kaolinite-dimethyl sulfoxide increased from 53.3% to 70.9% through the introduction of an inorganic acid. The intercalation time of kaolinite-methyl alcohol compound sharply decreased from 336 h from 12 h, and IR significantly increased from 9.2% to 41.8%. The kaolinite-stearic acid intercalation product was successfully and efficiently prepared through three rounds intercalation based on the kaolinite-dimethyl sulfoxide and kaolinite-methyl alcohol compound. The intercalated kaolinite particles had a physical dispersion in styrene butadiene rubber (SBR) matrix. The scorch time (t10) and curing time (t90) of the filled SBR composites decreased simultaneously relative to pure SBR, but the minimum torque and maximum torque presented no obvious change. The kaolinite-stearic acid intercalation gave a progressive reinforcement on mechanical properties of the filled styrene butadiene rubber composite. The tear strength and tensile strength of the SBR composite filled by kaolinite-stearic acid intercalation compound at 50 phr loading were 28.3 kN/m and 8.7 Mpa, respectively. The reinforcement of mechanical properties of the filled SBR composite is attributed to the fine dispersion of kaolinite lamellar-like structure in rubber matrix with restriction for rubber chains motion via trapping rubber chains in the house-of-cards structure and strong interaction with rubber chains via surface functional groups.

Zirconia-Intercalated Kaolinite: Synthesis, Characterization, and Evaluation of Metal-Ion Removal Activity

AbstractThe intercalation of kaolinite through the insertion of ions or molecules amongst the structural aluminosilicate layers is a vital process in numerous clay-based applications and products. Layer neutrality and hydrogen bonding limits direct intercalation into kaolinite, other than for small molecules. Synthesizing zirconia-intercalated kaolinite is not a straightforward matter. To overcome this barrier, raw Egyptian kaolin (UnK) or its acid-activated product (HK) was sonicated and impregnated in aqueous ZrOCl2·8H2O solution followed by thermal treatment at various temperatures (100, 200, 300, and 500°C). The intercalation process was confirmed using various spectroscopic and analytical techniques. The direct intercalation of ZrO2 into the kaolinite layers was observed even through a mild thermal treatment (100, 200, and 300°C). The mechanism of intercalation was suggested to occur by binding ZrO2 to the Si/AlO groups with a preference for the acid-activated HK, causing variable enlargements of the basal spacing and producing very perturbed layers. Interestingly, the surface area increased by 250% as a result of zirconia intercalation. Scanning electron microscopy (SEM) images showed a remarkable improvement in the stacking order of the kaolinite particles. The impact of ZrO2 intercalation into kaolinite also enhanced its adsorption efficiency for Pb2+, Cu2+, and Cd2+ ions. Preliminary investigations showed that the zirconia-intercalated HK demonstrated a removal efficiency, which is three times greater than that of pristine HK. The adsorption tendency toward Pb2+ ions was greater than those of Cu2+ and Cd2+ and followed the order: Pb2+ >> Cu2+ > Cd2+. The study suggests that the chemical modification of kaolin by zirconia via a direct intercalation technique, which greatly improves its functionality as demonstrated by the selective sorption of heavy metal ions, is worthy of further study.

Insights on the intercalation mechanism of the coal-bearing kaolinite intercalation based on experimental investigation and molecular dynamics simulations

Insights on the intercalation mechanism of the coal-bearing kaolinite intercalation based on experimental investigation and molecular dynamics simulations

A kaolinite-tetrabutylphosphonium bromide intercalation compound as an effective intermediate for intercalation of bulky organophosphonium salts

A kaolinite-tetrabutylphosphonium bromide (TBPBr) intercalation compound (Kaol-TBPBr) underwent intercalation of dodecyltributylphosphonium bromide (C12TriBPBr), while a kaolinite-dimethyl sulfoxide (DMSO) intercalation compound (Kaol-DMSO) and methoxy-modified kaolinite (MeO-Kaol) showed no such capability. As for the reaction of Kaol-TBPBr and C12TriBPBr, the X-ray diffraction (XRD) patterns revealed expansion of the basal spacing from 1.53 nm of Kaol-TBPBr to 2.10 nm. Fourier transform infrared, solid-state 13C nuclear magnetic resonance (NMR) with cross polarization and magic angle spinning (13C CP/MAS NMR) spectroscopies and the C/P and the Br/P molar ratios indicated intercalation of C12TriBPBr between the layers of kaolinite upon removal of the pre-intercalated TBPBr. As concerns the reactions of Kaol-DMSO and C12TriBPBr, the XRD patterns exhibited no difference as compared to that of Kaol-DMSO or the decrease in basal spacing from the 1.12 nm of Kaol-DMSO to the 0.72 nm of pristine kaolinite. With respect to the reactions of MeO-Kaol with C12TriBPBr, the XRD patterns displayed no expansion of the basal spacing from 0.86 nm of MeO-Kaol. Kaol-TBPBr was also used as an intermediate for successful intercalation of relatively bulk organophosphonium salts, hexadecyltributylphosphonium bromide, tetradecyltrihexylphosphonium chloride and tetraoctylphosphonium bromide. These results clearly reveal the versatility of Kaol-TBPBr as an effective intermediate for use in kaolinite intercalation chemistry.

Grafting of L-proline and L-phenylalanine amino acids on kaolinite through synthesis catalyzed by boric acid

The amidation reaction catalyzed by boric acid between the amino acids proline and phenylalanine and the alkoxide 3-aminopropyltriethoxysilane was studied. Afterwards, the modified alkoxide was used to functionalize the clay mineral kaolinite. The hybrid material was characterized by powder X-ray diffraction, molecular absorption spectroscopy in the infrared region, thermal analysis and scanning electron microscopy, to understand the influence of the reaction time on the kaolinite intercalation process, in order to improve this functionalization route for both amino acids. The reaction times evaluated varied from 0 to 24 h, keeping the reflux temperature fixed at 180 °C, being then reacted with kaolinite previously intercalated with dimethyl sulfoxide (DMSO). After 24 h of reaction the modified alkoxide interacted effectively, replacing the DMSO molecules and resulting in the formation of covalent bonds between the modified alkoxide and the clay. The material showed greater dispersion of the organic phase along the layered matrix, and significantly increased its thermal stability, with maximum loss at 320 °C. The sample containing phenylalanine was more agglomerated than that containing proline, with 2.4 times in mol number. In all cases, the crystallinity of the material decreased by the interaction of the modified alkoxide with the kaolinite matrix, the modified alkoxide being partially outside the interlayer space because of its large molecular size.

Flame Retardancy and Thermal Behavior of an Unsaturated Polyester Modified with Kaolinite-Urea Intercalation Complexes.

Organic modified kaolinite-urea intercalation complex (KUIC) was prepared using dimethyl sulfoxide (DMSO) as the precursor of kaolinite intercalation. Its structure was characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). Subsequently, as a synergistic agent, KUIC was combined with flame retardant ammonium polyphosphate (APP) to improve the flame retardant and smoke suppression performance of unsaturated polyester (UP) resin. A cone calorimeter (CONE) was used to study its flame retardancy and smoke suppression, and a scanning electron microscope (SEM) and thermogravimetry (TG) were used to study the micro morphology of the char and flame retardant mechanism. The results show that 12 phr of APP and 3 phr of KUIC were doped into UP to obtain a 28.0% limiting oxygen index (LOI) value. Compared with UP, the heat release rate and smoke production of UP/APP/KUIC composites were greatly decreased. Meanwhile, KUIC indeed enhanced the mechanical properties of UP.

Glowing kaolinite intercalated with N-Methyl imidazole and Eu3+/Tb3+ salts and potential application in UV-to-red light conversion

Kaolinite, one of the most ubiquitous clay minerals on the earth, is a hydrated aluminum disilicate with the composition of Al2Si2O5(OH)4, 1:1 dioctahedral and structurally asymmetric layers. This type of lamella mineral provides a platform to create artificially functional materials. Herein, we present a facile approach to prepare the glowing Kaolinites via a stepwise of intercalation of Kaolinite with N-Methyl imidazole (abbr. NMI) and Eu3+/Tb3+ nitrate salts in sequence, which are labeled as K-NMI-Eu and K-NMI-Tb, respectively, and characterized by microanalysis, thermogravimetric (TG), IR spectroscopy, powder X-ray diffraction techniques. Under ultraviolet irradiation, K-NMI-Eu and K-NMI-Tb emit the characteristic luminescence of Eu3+/Tb3+ ion with quantum yields of 25.5% (Eu3+) and 16.3% (Tb3+), respectively. We further fabricated the composite films of K-NMI-Eu with polyvinylidene fluoride (PVDF), K-NMI-Eu@PVDF-X (X = 1, 2, 5 and 10%, representing the mass percentage of K-NMI-Eu in film). The mechanical performances of composite films are almost the same as that of the pure PVDF film even if the X value is up to 10%. K-NMI-Eu@PVDF-10% emits intense red luminescence under ultraviolet irradiation at ambient condition, indicating that K-NMI-Eu is a good ultraviolet-converted-red light material potentially used for the agricultural light conversion film.

Effects of bleaching and functionalization of kaolinite on the mechanical and thermal properties of polyamide 6 nanocomposites.

Polyamide 6 nanocomposites (PA6)/kaolinite were prepared by melt compounding. First, kaolinite was bleached via a solvothermal reaction using oxalic acid as a bleaching agent; then, the bleached product was modified using dimethylsulfoxide (DMSO) and subsequently methanol (MeOH) via a displacement method. Thus, cetyltrimethyl ammonium bromide (CTAB) and triethoxy(octyl)silane (TEOS) molecules were intercalated into kaolinite nano-platelets. Seven types of nanocomposites were prepared using pristine, bleached or intercalated kaolinite. The kaolinite powder and the nanocomposite specimens were characterized by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), thermal analysis, scanning electronic microscopy (SEM), whiteness index and tensile tests. The influence of the bleaching process of kaolinite and the intercalation methods on the whiteness index of the nanocomposites was also observed, in which the whiteness index of the functionalized kaolinite nanocomposites was enhanced by up to 10.65% when compared to neat PA6. The thermal results revealed that the intercalation and functionalization greatly affect the thermal stability of the virgin polymer. On the other hand, the intercalation of kaolinite enhances the dispersion/distribution, improves the interfacial adhesion, and increases the aspect ratio of the kaolinite nanoparticles; this affords remarkable nanocomposite property enhancements, represented by a high Young's modulus value of 4.68 GPa and a maximum percentage growth of 80.6% for silane-grafted kaolinite nanoparticles at just 8 wt%.

Enhanced interlayer trapping of Pb(II) ions within kaolinite layers: intercalation, characterization, and sorption studies

Lead (Pb(II)) pollution in water poses a serious threat to human health in many parts of the world. In the past decades, research has been aimed at developing efficient and cost-effective methods to address the problem. In this study, dimethyl sulfoxide (DMSO) and potassium acetate (K-Ac) intercalated kaolinite complexes were synthesized and subsequently utilized for Pb(II) removal from water. The intercalation of kaolinite with DMSO was found to be useful for expanding the interlayer space of the clay mineral from 0.72 to 1.12 nm. Kaolinite intercalation with K-Ac (KDK) increased the interlayer space from 1.12 to 1.43 nm. The surface area of KDK was found to be more than threefold higher as compared to natural kaolinite (NK). Batch experimental results revealed that the maximum Pb(II) uptake capacity of KDK was 46.45 mg g−1 which was higher than the capacity of NK (15.52 mg g−1). Reusability studies showed that KDK could be reused for 5 cycles without substantially losing its adsorption capacity. Furthermore, fixed-bed column tests confirmed the suitability of KDK in continuous mode for Pb(II) removal. Successful application of intercalated kaolinite for Pb(II) adsorption in batch and column modes suggests its application in water treatment (especially removal of divalent metals).

Influencing parameters of direct homogenization intercalation of kaolinite with urea, dimethyl sulfoxide, formamide, and N-methylformamide

A detailed investigation of the influencing parameters of the homogenization intercalation method was carried out for a medium-defect kaolinite (Hinckley index = 0.8). The direct synthesis of kaolinite-urea, kaolinite-dimethyl sulfoxide, kaolinite-formamide, and kaolinite-N-methylformamide complexes was systematically studied and the effect of the reaction parameters was analyzed. The Avrami-Erofeev equation modified for diffusion was applied to describe the intercalation kinetics. The present study revealed that the homogenization method reduces the shortcomings of the conventional solution and mechanochemical methods. The homogenization method requires an order of magnitude lower amount of reagents, and results in low-defect complex structures identical to those obtained by the solution method, with a high degree of intercalation. Comparing the studied reaction parameters, the intercalation of kaolinite with urea, dimethyl sulfoxide, and N-methylformamide strongly depends on the aging temperature. Heating at slightly above room temperature (60 °C or 80 °C) makes it possible to complete the intercalation in a short time, while at room temperature the maximum intercalation can take ten times longer. In the case of formamide, the aging temperature has a weaker effect; the reaction rate constant of its intercalation did not increase significantly up to 50 °C.

Effect of alkylamine chain length on high-temperature phase transformation and thermal decomposition process of kaolinite intercalation compounds

The structural changes and thermal decomposition of kaolinite (Kaol) intercalation compounds during heating process limit their application in polymers which need to be heated during the preparation process. In this study, homologous compounds, namely, hexylamine (HEA) and octadecylamine (OCA), were used to intercalate Kaol to explore the effect of molecular chain length on the structural stability and thermal decomposition of intercalated compounds. After the intercalation by HEA and OCA, the expansion only occurred along the C-axis, and the basal spacing increased to 28.7 and 57.3 Å, respectively. The morphology of Kaol changed remarkably, and all appeared curly. Compared with Kaol/HEA intercalation compounds, the Kaol/OCA intercalation compounds had better curling effect due to their different molecular chain length. The thermal decomposition process of Kaol/alkylamine intercalation compounds can be divided into two distinct stages. The molecules that adhered to the surface of the nanoscrolls and existed in the lumen of nanoscrolls began to deintercalate in the first step, and the other molecules that intercalated Kaol layers began to decompose in the second step. Thus, Kaol can be used as a potential carrier material, a carrier of sustained-release drug, or a carrier material for the catalyst. The reaction is regulated by controlling the temperature of the reaction.

Improvement of water vapor barrier and mechanical properties of sago starch‐kaolinite nanocomposites

AbstractThe composite films of sago starch were prepared by incorporation of various amount of kaolinite (K) and kaolinite intercalated by dimethyl sulfoxide (DMSO) (KD) via solution blending method in order to reduce the water vapor transmission and enhance mechanical properties of starch based films. The kaolinite intercalation by DMSO and the composite films were characterized by using X‐ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscope techniques. The result showed that well‐dispersed kaolinite layers were delaminated in the starch matrix attesting to intercalate and exfoliate composite films. The effect of kaolinite content on the water vapor transmission and tensile properties of the composite films was investigated. The water vapor transmission of the starch film (neat starch film ca. 0.132 g.cm3/h) decreased with the addition of K and KD to the starch. It was also observed that the maximum tensile strength (5.18 MPa) was attained for the composite film with 4% by weight of clay content. The improvement in the tensile strength and modulus of starch‐based composites was due to the strong interfacial interaction between matrix and kaolinite clay, correlating to the change of morphology of the starch composite films as revealed by scanning electron microscopy.

Facile one-step microwave-assisted modification of kaolinite and performance evaluation of pickering emulsion stabilization for oil recovery application

A facile one-step microwave-assisted method was proposed for kaolinite intercalation and grafting. The structure, morphology, composition, and size distribution of kaolinite sheets were investigated using various methods, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric (TG) analysis. The potential application of the modified kaolinite as an oil/water emulsion stabilizer was studied. The results verified that intact kaolinite sheets were obtained. The dodecane/water emulsion stabilized by the modified kaolinite remained stable for more than 60 days. The effective performance suggests that the effectiveness of the proposed kaolinite modification method may be useful for Pickering emulsion stabilization in oil recovery applications.

Preparation of azobenzene-intercalated kaolinite and monitoring of the photoinduced activity

AbstractSystems consisting of layered structures and photoactive molecules have been studied extensively. The structures of resulting complexes may be controlled by UV–Vis radiation, which subsequently affects their materials properties. This study describes a synthesis route for obtaining a photoresponsive kaolinite intercalation compound. The material was prepared by co-intercalating azobenzene and benzylalkylammonium chlorides into a methoxy form of kaolinite. The resultant materials possessed large basal spacing values in the range of 45–55 Å. The UV–Vis and Fourier-transform infrared spectroscopy analyses confirmed the reversible photoisomerization of azobenzene upon exposure to UV and Vis radiation. This phenomenon was significantly influenced by the type and amount of co-intercalated molecules. Upon multiple trans–cis conversions, the azobenzene partially evaporated. For the first time, a kaolinite-based material was prepared that exhibited photochromic behaviour upon UV and Vis irradiation.