X-ray photon detection is important for a wide range of applications. The highest demand, however, comes from medical imaging, which requires cost-effective, high-resolution detectors operating at low photon flux, therefore stimulating the search for novel materials and new approaches. Recently, hybrid halide perovskite CH3NH3PbI3 (MAPbI3) has attracted considerable attention due to its advantageous optoelectronic properties and low fabrication costs. The presence of heavy atoms, providing a high scattering cross-section for photons, makes this material a perfect candidate for X-ray detection. Despite the already-successful demonstrations of efficiency in detection, its integration into standard microelectronics fabrication processes is still pending. Here, we demonstrate a promising method for building X-2 ray detector units by 3D aerosol jet printing with a record sensitivity of 2.2 x 10 8 µC Gyair -1 cm -2 when detecting 8 keV photons at dose-rates below 1 Gy/s (detection limit 0.12 Gy/s), a fourfold improvement on the best-in-class devices. An introduction of MAPbI3-based detection into medical imaging would significantly reduce health hazards related to the strongly ionizing Xrays photons.

The controllable synthesis of rutile TiO 2 single crystal particles with preferential orientation of {111} facets still remain a scientific and technological challenge. Here, we developed a facile route to fabrication of rutile TiO 2 nanorod crystals (RTiO 2 NRs) having high ratios of oxidative {111} to reductive {110} surfaces. RTiO 2 NRs were synthesized using a peroxo-titanium complex (PTC) approach, which was controlled by changing the Ti/H 2 O 2 ratio.The thus obtained RTiO 2 NRs revealed a high tendency to agglomerate through orientationdependent attachment along the {110} facets. This resulted in an increased {111}/{110} surface ratio and lead to a markedly improved photocatalytic activity of RTiO 2 NRs aggregates. The reported findings illustrate the rich potential of the herein proposed facile and energy-efficient synthesis of nanostructured rutile TiO 2 -based photocatalysts.

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The influence of modification and vacuum/supercritical CO (scCO) drying methods on the surface properties, morphology and thermal stability of cellulose nanocrystals (NC) was presented in this study. Introduction of reactive vinyl groups on NC surface was performed by either direct esterification with oleic acid, linseed or sunflower oil fatty acids; or by amidation of maleic acid/ethylene diamine with methyl ester of fatty acid. Obtained modified NC (m-NC) were characterized using FTIR and Raman spectroscopy; and by determination of acid, iodine and ester values. Structural analysis of m-NC showed varieties of forms, from spongy to nanostructural non-uniform layered morphology with observable agglomeration, which confirmed morphology dependence on modification/processing methods Thermogravimetry-MS spectrometry showed different thermal stability and degradation pathways of NC/m-NC. Incorporation of 1 wt% of reactive m-NC in unsaturated polyester lead to high performance nanocomposites and contributed to increase of stress at break in the range from 76 to 93%.

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