Aromatic polyamides represent an important class of polymeric materials from both the
academic and the industrial points of view. Unfortunately, because of strong intermolecular interactions
mainly due to hydrogen bonding, their solubility in common organic solvents is often extremely poor. In
most cases, this drawback does not allow aramide molecular characterization. In the present work, the
above difficulties have been overcome by a functionalization reaction leading to N-allyl derivatives of the
parent aramide, that are easily soluble in organic solvents. Poly(p-phenylene terephthalamide) has been
chosen as the reference aramide to be functionalized, on the basis of its industrial relevance as well as
its insolubility in all organic media. Molar mass distribution of its N-allylated derivative has been obtained
by SEC, using chloroform + 0.3% acetic acid as mobile phase, thus allowing full molecular characterization
of the parent polymer.
Although organic solar cells have surpassed the 17% power conversion efficiency threshold, commercial modules efficiencies are only around 4–5%. One of the reason is the lack of effective solution‐processable hole transport materials that are a key element for the scale‐up on roll‐to‐roll printing equipments and the commercial development. Herein, a class of novel vanadium and molybdenum polyoxometallate salts are developed that, alone or in combination with a traditional poly(ethylene‐3,4‐dioxytiophene):poly(styrene sulfonate) (PEDOT:PSS) layer, can be used as anodic buffer layer in inverted polymer solar cells. These materials exhibit work function values around 5.8 eV that match well with highest occupied molecular orbital energies of typical polymer donors. They are tested with different widely used active systems, including PTB7:PC71BM, PV2000:PCBM, and PffBT4T:PC71BM. Vanadium and molybdenum polyoxometallate can be deposited from solutions and, contrary to PEDOT:PSS used alone, do not cause a drop of performances compared with evaporated molybdenum oxide (e‐MoOx); on the contrary, in the best cases they achieve similar performances to e‐MoOx. Slot‐die‐coated PV2000:PCBM solar cells on flexible substrate achieve a remarkable power conversion efficiency of almost 7.6%.
Catalytic systems for methane combustion, with Rh and Pt in a BaZrO3-based perovskite, were synthesized at the University of L’Aquila and tested at close to industrial conditions at the KTH Energy Centre in Stockholm. Because of the resistance to high temperature of BaZrO3 (up to ∼2600 °C), such systems are suitable for resolving stability problems frequently encountered with high-temperature operations. Furthermore, these perovskites contain the noble metal in a high oxidation state, giving rise to very active compounds. They also result in ultra-low emissions, compatible with legislation in such places as southern California and Japan.
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