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The development of cheap and robust heterogeneous catalysts for the Meerwein‐Ponndorf‐Verley (MPV) reduction is desirable due to the difficulties in product isolation and catalyst recovery associated with the traditional use of homogeneous catalysts for MPV. Herein, we show that microwave heated γ‐Al2O3 can be used for the reduction of aldehydes to alcohols. The reaction is efficient and has a broad substrates scope (19 entries). The products can be isolated by simple filtration, and the catalyst can be regenerated. With the use of microwave heating, we can direct the heating to the catalyst rather than to the whole reaction medium. Furthermore, DFT was used to study the reaction mechanism, and we can conclude that a dual‐site mechanism is operative where the aldehyde and 2‐propoxide are situated on two adjacent Al sites during the reduction. Additionally, volcano plots were used to rationalize the reactivity of Al2O3 in comparison to other metal oxides. [ABSTRACT FROM AUTHOR]

While photovoltaic blends based on non‐fullerene acceptors are touted for their thermal stability, this type of acceptor tends to crystallize, which can result in a gradual decrease in photovoltaic performance and affects the reproducibility of the devices. Two halogenated indacenodithienothiophene‐based acceptors that readily co‐crystallize upon mixing are studied, which indicates that the use of an acceptor mixture alone does not guarantee the formation of a disordered mixture. The addition of the donor polymer to the acceptor mixture readily suppresses the crystallization, which results in a fine‐grained ternary blend with nanometer‐sized domains that do not coarsen due to a high Tg ≈ 200 °C. As a result, annealing at temperatures of up to 170 °C does not markedly affect the photovoltaic performance of ternary devices, in contrast to binary devices that suffer from acceptor crystallization in the active layer. The results indicate that the ternary approach enables the use of high‐temperature processing protocols, which are needed for upscaling and high‐throughput fabrication of organic solar cells. Further, ternary devices display a stable photovoltaic performance at 130 °C for at least 205 h, which indicates that the use of acceptor mixtures allows to fabricate devices with excellent thermal stability. [ABSTRACT FROM AUTHOR]

Accurate complex dielectric functions are critical to accelerate the development of rationally designed metal alloy systems for nanophotonic applications, and to thereby unlock the potential of alloying for tailoring nanostructure optical properties. To date, however, accurate alloy dielectric functions are widely lacking. Here, a time‐dependent density‐functional theory computational framework is employed to compute a comprehensive binary alloy dielectric function library for the late transition metals most commonly employed in plasmonics (Ag, Au, Cu, Pd, Pt). Excellent agreement is found between electrodynamic simulations based on these dielectric functions and selected alloy systems experimentally scrutinized in 10 at% composition intervals. Furthermore, it is demonstrated that the dielectric functions can vary in very non‐linear fashion with composition, which paves the way for non‐trivial optical response optimization by tailoring material composition. The presented dielectric function library is thus a key resource for the development of alloy nanomaterials for applications in nanophotonics, optical sensors, and photocatalysis. [ABSTRACT FROM AUTHOR]

Fuel cells have the potential to play an important role in sustainable energy systems, provided that catalysts with higher activity and stability are developed. In this work, it is found that thin alloy films of single-target cosputtered platinum-yttrium exhibit up to seven times higher specific activity (13.4 ± 0.4 mA cm−2) for the oxygen reduction reaction (ORR) than polycrystalline platinum, and up to one order of magnitude higher mass activity (3.5 ± 0.3 A mg−1) than platinum nanoparticles. These alloys have the highest reported ORR activity for an as-deposited material, i.e., without any additional chemical or thermal treatment. The films show an improvement in stability over the same materials in nanoparticulate form. Physical characterization shows that the thin films form a platinum overlayer supported on an underlying alloy. The high activity is likely related to compressive strain in that overlayer. As sputtering can be used to mass-produce fuel cell electrodes, the results open new possibilities for the preparation of platinum-rare earth metal alloy catalysts in commercial devices. [ABSTRACT FROM AUTHOR]

Light absorption in plasmonic nanoantennas constitutes an interesting way of enhancing catalytic reactions occurring at surfaces of metals nanoparticles by forming hot electron–hole pairs. These can either directly transfer to empty orbitals of adsorbed species on the nanoparticle surface or thermalize via electron–phonon coupling and enhance reaction rates via a photothermal reaction channel. While this scheme, in principle, can be efficient for the well‐known plasmonic materials Ag and Au due to their large optical cross‐sections, other transition metals, which exhibit excellent catalytic properties, have spectrally broad and weak plasmon resonances. Thus, lower plasmon‐induced electron–hole pair excitation is expected, especially for sub‐10 nm nanoparticles, typical in heterogeneous catalysis. Here, a solution is presented to circumvent these limitations by challenging the established picture that plasmonic nanoparticles also constitute catalytically active entities in a plasmon mediated hot electron catalysis concept. Light absorption in catalyst nanoparticles can be engineered via an adjacent noble metal plasmonic nanoantenna that efficiently collects incident radiation with low losses, and couples it into the catalytic particles where the energy is dissipated due to the intrinsically high optical losses in transition metals at near‐visible frequencies. Absorption enhancement of 1–2 orders of magnitude is predicted in 3–4 nm sized Pd catalyst nanoparticles. [ABSTRACT FROM AUTHOR]

The high activity for the oxygen reduction reaction of thin platinum‐yttrium films is highlighted by Niklas Lindahl and co‐workers in article number 1700311. The alloy thin films are formed by sputtering using plasma (purple) from a target of platinum (gray) with attached foils of yttrium (blue). In acid, a strained platinum overlayer is formed. The strained surface provides improved activity for the reduction of oxygen (red), which is rate limiting when converting protons (white) into water while producing electrical energy in fuel cells. [ABSTRACT FROM AUTHOR]