Recently, polymer composites reinforced with low fractions of thermomiotic nanoceramics have triggered a lot of research. The efforts have been focused on achieving considerable reduction of the coefficient of thermal expansion (CTE) of polymeric materials without deterioration of other physical properties. In this context, polyethylene (PE) composites reinforced with different loads of Al 2 Mo 3 O 12 nanofillers (0.5-4 mass %) were fabricated by micro-compounding. To enhance the interfacial interaction between the two components, chemical functionalization of Al 2 Mo 3 O 12 was performed with vinyltrimethoxysilane (VTMS) prior to micro-compounding. Infrared spectroscopy and thermogravimetry demonstrated the successful grafting of VTMS on the Al 2 Mo 3 O 12 surface. The composites showed strongly decreased CTEs, up to 46 % reduction for loadings of 4 mass % compared with neat PE, suggesting intimate filler-matrix interactions. The variation of CTEs of the composites in terms of the filler fraction was successfully described by Turner's model allowing calculation of the bulk modulus of monoclinic Al 2 Mo 3 O 12 (13.6 ± 2.6 GPa), in agreement with the value obtained by an ultrasonic method. The thermal stability of the composites was improved, although the addition of functionalized fillers decreased the degree of crystallinity of the PE to a small extent. The Young's modulus and yield strength of the composites increased from 6.6 to 19.1 % and 4.0-6.0 %, respectively, supporting the existence of strong filler-matrix interactions, contributing to an efficient load transfer. Finite element analysis of thermal stresses Electronic supplementary material The online version of this article (

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Zero thermal expansion phases from the A 2 M 3 O 12 and related thermomiotic (negative thermal expansion) families are natural candidates for applications where high thermal shock resistance is the principal requirement. However, their mechanical properties are largely unknown, as are sintering routes for consolidation into bulk objects. Therefore, a preliminary case study on the effect of microstructure on mechanical strength and thermal shock resistance of Al 2 W 3 O 12 has been performed. All thermal and mechanical properties necessary for calculation of thermal shock resistance figures of merit have been measured experimentally. Tensile strengths were measured by four-point flexural test and analyzed by the Weibull method. The microstructure of bulk specimens, conventionally pressureless sintered at 1273 K, was coarse-grained, containing microcracks, and inhomogeneous with respect to density due to the agglomeration of nanoparticles, and led to low tensile strength. Despite this, thermal shock resistance features evaluated for Al 2 W 3 O 12 are encouraging. The Hasselman figure of merit for thermal shock resistance for severe heating conditions of Al 2 W 3 O 12 was 120 K, comparable to sapphire, the state-ofthe-art material for some advanced thermal shock resistance applications. This study shows that zero thermal expansion phases from the A 2 M 3 O 12 family have potential to be transformed into useful engineering ceramics for thermal shock resistance applications.

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The efficiency of photo-oxidation of pollutants catalysed by semiconductors is still limited for real-world applications due to several drawbacks, such as a) insufficient absorption of visible radiation, which predominates in solar spectrum, b) rapid free electron to hole recombination, c) small surface area, built from equilibrium crystallographic facets with low adsorption capacities and d) photo-corrosion. The present study disclosures new mesoporous heterostructures, built from exfoliated lepidocrocite-like ferrititanates and TiO 2 (anatase)-acetylacetone charge transfer complex, capable of reducing free electron-to-hole recombination rate through a robust charge separation and sensitive to the visible light spectrum. The synthesis route is based on soft-chemistry and low temperature calcination at 300°C. Two different partially pillarized heterostructures, denoted as HM-1 and HM-2, have been synthesized. It was observed that the heterostructure HM-1 was four times more active toward photocatalytic degradation of NO gas in comparison to the benchmark photocatalytic material P25. The lower activity of the heterostructure HM-2, comparable to that of P-25, was attributed to the high value of Urbach energy that indicates high number of defect sites within energy band-gap of the constituent semiconductor components. [Ti] anatase/[Ti] ferrititanate mol ratio might also play a role in photocatalytic efficiency.