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.

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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.

Ibuprofen (IBU) is one of the most-sold anti-inflammatory drugs in the world, and its residues can reach aquatic systems, causing serious health and environmental problems. Strategies are used to improve the photocatalytic activity of zinc oxide (ZnO), and thosethat involvethe inclusion of metalhave received special attention. The aim of this work was to investigate the influence of the parameters and toxicity of a photoproduct using zinc oxide that contains cerium (ZnO-Ce) for the photodegradation of ibuprofen. The parameters include the influence of the photocatalyst concentration (0.5, 0.5, and 1.5 g L−1) as well as the effects of pH (3, 7, and 10), the effect of H2O2, and radical scavengers. The photocatalyst was characterized by Scanning Electron Microscopy-Energy Dispersive Spectroscopy, Transmission electron microscopy, Raman, X-Ray Diffraction, surface area, and diffuse reflectance. The photocatalytic activity of ibuprofen was evaluated in an aqueous solution under UV light for 120 min. The structural characterization by XRD and SEM elucidated the fact that the nanoparticle ZnO contained cerium. The band gap value was 3.31 eV. The best experimental conditions for the photodegradation of IBU were 60% obtained in an acidic condition using 0.50 g L−1 of ZnO-Ce in a solution of 20 ppm of IBU. The presence of hydrogen peroxide favored the photocatalysis process. ZnO-Ce exhibited good IBU degradation activity even after three photocatalytic cycles under UV light. The hole plays akey role in the degradation process of ibuprofen. The toxicity of photolyzed products was monitored against Artemia salina (bioindicator) and did not generate toxic metabolites. Therefore, this work provides a strategic design to improve ZnO-Ce photocatalysts for environmental remediation.