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The "on‐demand" capture and utilization of CO2 is effectively realized with a readily accessible dual function organic composite. The covalent and controlled derivatization of graphene oxide (GO) surface with naturally occurring arginine led to a "smart" material capable of capturing (chemisorption) CO2 from high‐purity flue‐gas as well as low‐concentration streams (i. e. direct air capture) and concomitant chemical activation toward the incorporation into cyclic carbonates. The overall integrated CO2 capture and conversion (ICCC) strategy has been fully elucidated mechanistically via dedicated computational, spectroscopic and thermal analyses. [ABSTRACT FROM AUTHOR]

Trigonal‐prismatic coordinated transition metal dichalcogenides (TMDCs) are formed from stacked (chalcogen)–(transition metal)–(chalcogen) triple layers, where the chemical bond is covalent within the triple layers and van der Waals (vdW) forces are effective between the layers. Bonding is at the origin of the great interest in these compounds, which are used as 2D materials in applications such as catalysis, electronics, photoelectronics, sensors, batteries and thermoelectricity. This paper addresses the issue of modelling the structural disorder in multilayer TMDCs. The structural model takes into account stacking faults, correlated displacement of atoms and average crystallite size/shape, and is assessed by simulation of the X‐ray diffraction pattern and fitting to the experimental data relative to a powdered sample of MoS2 exfoliated and restacked via lithiation. From fitting, an average crystallite size of about 50 Å, nearly spherical crystallites and a definite probability of deviation from the fully eclipsed atomic arrangement present in the ordered structure are determined. The increased interlayer distance and correlated intralayer and interlayer atomic displacement are attributed to the presence of lithium intercalated in the vdW gap between triple layers (Li/Mo molar ratio of about 0.06). The model holds for the whole class of trigonal‐prismatic coordinated TMDCs, and is suitably flexible to take into account different preparation routes. [ABSTRACT FROM AUTHOR]

Nanolubricants, thanks to their ability to reduce friction and wear, are increasingly studied in the transport and automotive sectors. These systems are generally produced with a two‐step procedure by dispersing nanoparticles into base oils. Very recently, one‐step methods have received increasing attention for the production of highly stable nanosuspensions at lower cost. Degradation‐decomposition of the base oil can however occur during the synthesis affecting the final performances. In this work, copper‐based nanolubricants were produced using a new procedure that preserves the base oil from the degradation induced by the synthesis and allows producing highly stable nanolubricant. The produced fluid showed a monodisperse distribution of nanometric particles and a good stability up to at least 60 days from its production. The as‐produced nanolubricants showed notable performance reducing the friction coefficient even up to 32.7% for Cu concentration of 0.01 vol% at 80°C. [ABSTRACT FROM AUTHOR]

A synthetic sequence for the preparation of fully conjugated 2,7-disubstituted fluorazone (9H-pyrrolo[1,2--a]indol-9-one) derivatives has been developed comprising an Elming–Clauson–Kaas-type pyrrole formation, POCl3-mediated ring closure, selective halogenation and elongation of the conjugated backbone through cross-coupling reactions. As a proof of principle, this methodology was used to prepare for the first time two organic D–π–A dyes containing the fluorazone moiety. The new compounds display broad absorption bands in the visible-light region when adsorbed on nanocrystalline TiO2 and electrochemical properties compatible with their employment as photosensitizers in dye-sensitized solar cells. Small-scale photovoltaic devices fabricated with the fluorazone dyes yielded power conversion efficiencies in the range of 2.1–2.4 %, which correspond to approximately 70 % of the efficiency obtained with the reference organic dye DF15 under the same conditions. [ABSTRACT FROM AUTHOR]

ZrB2-based laminates were produced by tape casting and pressureless sintered at 2150°C in argon atmosphere using silicon nitride as sintering aids. Two different configurations were considered: planar (tile) and tubular (roll). After sintering, the laminates reached different relative densities depending on their composition (with or without SiC additions as secondary phase) or the final shape (tiles or rolls). Traces of the formation of oxygen\xE2\x80\x90free crystalline phases such as B4C and BN were found in all samples. The RT flexural strength of bars cut from the tile configuration was mainly affected by the coarse microstructure, residual porosity, and layer stacking sequence. A very low scattering of the flexural strength values was registered in ZrB2-SiC laminates because of the homogeneous microstructure and the absence of any defects between the layers. Tape casting allowed the production of thin homogenous laminates with a significant reduction of weight and a careful microstructure control. [ABSTRACT FROM AUTHOR]