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Industrial development and urbanization have increased the emission of Volatile Organic Compounds (VOCs) into the atmosphere, causing environmental and health risks. Several approaches are used for their abatement, including chemical, thermo‐ and photo‐catalytic oxidations, but they are not fully satisfactory. In this work, a thermoplastic TiO2‐based photo‐catalyst was used as a coating layer of a glass‐reactor. Solar‐triggered photocatalytic degradation of ethanol, toluene, and acetone (used as model VOCs) highlights the better performance of the coated photoreactor than that of TiO2 nanopowder. The influence of the pollutant flow rate on the photodegradation performance of the system was also investigated, revealing an inverse relationship between degradation and flow rates. The experimental data suggest that our approach provides a cost‐effective and efficient way to boost the abatement of VOCs, useful for further industrial‐scale applications. The morphology and the compositional homogeneity of the nanocomposite coating were addressed through Field Emission Scanning Electron Microscopy coupled with Energy Dispersive X‐ray Analysis. [ABSTRACT FROM AUTHOR]

For the first time, the simultaneous synthesis and deposition of heterometallic porphyrin conjugated polymer thin films from a simple and scalable gas‐phase approach are reported. The oxidative chemical vapor deposition (oCVD) reaction of 5,15‐(diaryl) porphyrins chelated with different metal cations (M = Co(II), Ni(II), Zn(II), Cu(II), Pd(II)) readily yields the formation of new hetero‐metalated fused porphyrin tapes, such as evidenced by in‐depth high‐resolution mass spectrometry studies. The impact of the coreactants on the regioselectivity of the intermolecular dehydrogenative coupling reaction and the formation of double or triple bonds between the porphyrin units is demonstrated. The oCVD reaction of multiple porphyrins brings the possibility to easily engineer the chemical features and the electronic and optoelectronic properties of these highly conjugated porphyrin polymers. Particularly, it is demonstrated that porphyrin conjugated polymers having different chelated metal cations can achieve higher electrical conductivities and promote narrower bandgaps. The gas‐phase approach presented herein overcomes the main limitations of the conventional solution‐based approaches and opens the path to the engineering of a novel class donor–acceptor heterometallic polymers with high interest in several fields including multimetallic electrocatalysis, photocatalysis, sensing, and nonlinear optics applications. [ABSTRACT FROM AUTHOR]

Modulating the interfacial charge alignments by molecular engineering in an organic heterojunction device is a smart strategy to improve its conductivity, which can be exploited in high‐performance gas‐sensor development. Herein, the fabrication of new organic heterojunction devices based on porphyrin tapes and phthalocyanines and their potentiality in ammonia sensing at different relative humidity (rh) are investigated. The devices are built using dry approach relying on oxidative chemical vapor deposition for simultaneous synthesis, doping, and deposition of the porphyrin tape layer and physical vapor deposition of phthalocyanine layer. The association of the porphyrin tapes with copper phthalocyanine (CuPc) or its perfluorinated analogue (Cu(F16Pc)) in a bilayer device configuration reveals a nonlinear current–voltage characteristic, assigned to the formation of organic heterojunction at the bilayer interface. Cu(F16Pc)‐based devices reveal higher response, faster sorption kinetics, stable baseline, and less interference from rh fluctuations toward ammonia than CuPc‐based devices, which are attributed to more conducting interface in the former. Moreover, depending on the porphyrin tape associated, Cu(F16Pc)‐based devices exhibit sensitivity values 6.7 or 0.4% ppm−1 and detection limit of 1 ppm or 228 ppb allowing to obtain among the best NH3 sensors reported. [ABSTRACT FROM AUTHOR]