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Recently there has been a renewed interest in the development and use of pedagogical games, as they provide an interesting approach to the appropriation of knowledge in the context of active learning. However, most didactic games fail to completely implement a cycle of reflection and action, thereby fostering mostly lower-order thinking skills and memorization as opposed to critical thinking and problem solving skills. This limitation can be traced back to the ineffective carrot and stick approach to game design that is widely applied in the context of pedagogical games. In this article, we discuss the development of a pedagogical game in which the game elements were carefully chosen to seamlessly merge with the desired chemistry content and therefore create an engaging and fun learning experience. In particular, in order to allow complex concepts to naturally emerge from a simple set of rules, we followed the so-called European approach to game design. The resulting game, MOL (Mastering the Organic chemistry Laboratory), was tested with 77 students of ages between 19 and 21 enrolled in organic chemistry courses for chemical engineering majors and 26 students of ages between 17 and 18 enrolled in a 12th grade chemistry class. The results of these classroom implementations indicate that MOL clarifies several key concepts regarding organic reactions, particularly kinetic and thermodynamic aspects. Furthermore, they suggest that MOL can be effectively used to demonstrate how the aforementioned concepts interrelate in a real laboratory situation, therefore stimulating a sense of critical thinking.

The present work reports Förster resonance energy transfer (FRET) from 1,8-naphthalimide (NI) donors bound to the pore walls of mesoporous silicas to perylenediimide (PDI) acceptors doped into the mesochannels. Mesoporous organosilicas containing covalently bound NI were synthesized by co-condensation of tetraethylorthosilicate (TEOS) with N-(3-(triethoxysilyl)­propyl)-1,8-naphthalimide (TEPNI) in the presence of a block copolymer surfactant as a template. The resulting materials were highly ordered, presenting a 2D hexagonal structure, and displayed easily tunable optical properties, which could be controlled by the amount of NI in the sample. A sample prepared from a diluted TEPNI solution (SBANId) presented a blue, monomerlike emission. In contrast, when a concentrated TEPNI solution was used, the resulting material (SBANIc) displayed a green, excimerlike emission. For the FRET studies, N,N′-bis­(2,6-dimethylphenyl)-3,4,9,10-perylenediimide was doped into the pores of the SBANI samples from chloroform solutions. When excited at the NI absorption maximum (350 nm), PDI-doped SBANIc showed intense quenching of the NI emission band, even at very low PDI doping, with quenching efficiencies reaching nearly 80% with only 0.6 mol % PDI (PDI/NI ≈ 1:170). The emission of PDI was observed at higher doping ratios, even though the PDI hardly absorbs at 350 nm, thus evidencing FRET from the host NI to the guest PDI. SBANI materials with a suitable amount of the PDI dopant displayed a white emission, spanning the whole visible spectrum.

This naphthalene diimide derivative, DC18, forms highly conjugated semiconducting stacked assemblies over electrodes after electrochemical conditioning. These molecular materials are very efficient towards electrochemical photoreduction of oxygen under visible light.

Polyureas (PURs) are a competitive polymer to their analogs, polyurethanes (PUs). Whereas PUs’ main functional group is carbamate (urethane), PURs contain urea. In this revision, a comprehensive overview of PUR properties, from synthesis to technical applications, is displayed. Preparative routes that can be used to obtain PURs using diisocianates or harmless reagents such as CO2 and NH3 are explained, and aterials, urea monomers and PURs are discussed; PUR copolymers are included in this discussion as well. Bulk to soft components of PUR, as well as porous materials and meso, micro or nanomaterials are evaluated. Topics of this paper include the general properties of aliphatic and aromatic PUR, followed by practical synthetic pathways, catalyst uses, aggregation, sol–gel formation and mechanical aspects.

Addition of NaCl and LiCl salts to glycerol–urea synthesis leads to the formation of rods and small spheres of ZnO-NPs.

Mesoporous gamma-aluminas (γ-Al 2 O 3 ) were synthesized starting from an unusual precursor of polyoxohydroxide aluminum (POHA). This precursor was obtained from aluminum oxidation in alkaline water-ethanol solvent in the presence of d-glucose that induces the formation of a gel, which leads to the POAH powder after ethanolic treatment. Precipitated POHAs were calcined at different temperatures (300, 400, 700 and 900 °C) resulting in the metastable γ-Al 2 O 3 phase. Whereas at 300 °C no γ-Al 2 O 3 phase was formed, unexpectedly, mesoporous γ-Al 2 O 3 was obtained at 400 ºC having a high specific surface area (282 m 2 /g) and a narrow pore size distribution. At higher temperatures, the aluminas had the expected decrease in surface area: 166 m 2 /g (700 °C) and 129 m 2 /g (900 °C), respectively. The structural change from POHA to alumina calcined at 400 ºC occurs directly without the need to isolate the hydroxide or oxyhydroxide aluminum precursors. Both POHA and transition aluminas were characterized by Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), N 2 sorption and Scanning Electron Microscopy (SEM). These findings show an alternative route to produce high standard aluminas.

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