Poly(vinylidene fluoride)-Stabilized Black γ-Phase CsPbI Perovskite for High-Performance Piezoelectric Nanogenerators.

Halide perovskite materials have been recently recognized as promising materials for piezoelectric nanogenerators (PENGs) due to their potentially strong ferroelectricity and piezoelectricity. Here, we report a new method using a poly(vinylidene fluoride) (PVDF) polymer to achieve excellent long-term stable black γ-phase CsPbI and explore the piezoelectric performance on a CsPbI@PVDF composite film. The PVDF-stabilized black-phase CsPbI perovskite composite film can be stable under ambient conditions for more than 60 days and over 24 h while heated at 80 °C.

Metal-Insulator-Semiconductor Anodes for Ultrastable and Site-Selective Upconversion Photoinduced Electrochemiluminescence.

Photoinduced electrochemiluminescence (PECL) allows the electrochemically assisted conversion of low-energy photons into high-energy photons at an electrode surface. This concept is expected to have important implications, however, it is dramatically limited by the stability of the surface, impeding future developments. Here, a series of metal-insulator-semiconductor (MIS) junctions, using photoactive n-type Si (n-Si) as a light absorber covered by a few-nanometer-thick protective SiO /metal (SiO /M, with M=Ru, Pt, and Ir) overlayers are investigated for upconversion PECL of the model co-reactant system involving the simultaneous oxidation of tris(bipyridine)ruthenium(II) and tri-n-propylamine.

Evidence of the Ambipolar Behavior of Mo Cluster Iodides in All-Inorganic Solar Cells: A New Example of Nanoarchitectonic Concept.

Ambipolar materials such as carbon nanotubes, graphene, or 2D transition metal chalcogenides are very attractive for a large range of applications, namely, light-emitting transistors, logic circuits, gas sensors, flash memories, and solar cells. In this work, it is shown that the nanoarchitectonics of inorganic Mo cluster-based iodides enable to form thin films exhibiting photophysical properties that enable their classification as new members of the restricted family of ambipolar materials. Thus, the electronic properties of the ternary iodide Cs[{MoI}I] and those of thin films of the aqua-complex-based compound [{MoI}I(HO)]·HO were investigated through an in-depth photoelectrochemical study.

Nanoscaffold effects on the performance of air-cathodes for microbial fuel cells: Sustainable Fe/N-carbon electrocatalysts for the oxygen reduction reaction under neutral pH conditions.

Nanostructured electrocatalysts for microbial fuel cell air-cathodes were obtained via use of conductive carbon blacks for the synthesis of high performing 3D conductive networks. We used two commercially available nanocarbons, Black Pearls 2000 and multiwalled carbon nanotubes, as conductive scaffolds for the synthesis of nanocomposite electrodes by combining: a hydrothermally carbonized resin, a sacrificial polymeric template, a nitrogenated organic precursor and iron centers. The resulting materials are micro-mesoporous, possess high specific surface area and display N-sites (N/C of 3-5 at%) and Fe-centers (Fe/C < 1.

Polyoxothiometalate-Derivatized Silicon Photocathodes for Sunlight-Driven Hydrogen Evolution Reaction.

Silicon photocathodes coated with drop-casted {MoS}-based polyoxothiometalate assemblies are demonstrated to be effective for sunlight-driven hydrogen evolution reaction (HER) in acid conditions. These photocathodes are catalytically more efficient than that coated with the parent thiomolybdate incorporating an organic ligand, as supported by a higher onset potential and a lower overvoltage at 10 mA cm. At pH 7.