The impressive optoelectronic performance and low production cost of metal halide perovskites have inspired applications well beyond efficient solar cells. Herein, we widen the materials engineering options available for the efficient and selective photocatalytic oxidation of benzylic alcohols, an industrially significant reaction, using formamidinium lead bromide (FAPbBr3) and other perovskite-based materials. The best performance was obtained using a FAPbBr3/TiO2 hybrid photocatalyst under simulated solar illumination. Detailed optical studies reveal the synergetic photophysical pathways arising in FAPbBr3/TiO2 composites. An experimentally supported model rationalizing the large conversion enhancement over the pure constituents shows that this strategy offers new prospects for metal halide perovskites in photocatalytic applications.

Inspired by efficient perovskite solar cells, we developed a threecomponent hybrid perovskite-based solar photocatalyst cell, NiO x /FAPbBr 3 /TiO 2 , for C(sp 3 )−H bond activation with high selectivity (∼90%) and high conversion rates (3800 μmol g −1 h −1 ) under ambient conditions. Time-resolved spectroscopy on our photocatalytic cell reveals efficient exciton dissociation and charge separation, where TiO 2 and NiO x serve as the electron-and hole-transporting layers, respectively. The photogenerated charge carriers injected into TiO 2 and NiO x drive the challenging C− H activation reaction via the synergetic effects of their band alignment relative to FAPbBr 3 . The reaction pathway is investigated by controlling the free-radical formation, and we find that C−H activation is mainly triggered by hole oxidation. Besides aromatic alkanes, also the C(sp 3 )−H bond in cycloalkanes can be oxidized selectively. This work demonstrates a generic strategy for engineering highperformance photocatalysts based on the perovskite solar cell concept.

Metal trihalide perovskites are rapidly redefining the landscape of solid-state semiconductors utilized as active medium in photovoltaics and in light generation. Within this materials space, organic-inorganic hybrid formamidinium lead bromide (FAPbBr3) has arisen as a promising candidate for efferent light emitting devices, due to its capacity for sharp and bright green light emissions (530 nm). Herein we have applied a facile single-step ligand-mediated method for phasecontrolled synthesis of FAPbBr3 cube-and rod-shaped nanocrystals (NCs), starting from different ratios of precursor agents. Examining their structural and optoelectronic properties-using a combination of synchrotron X-ray diffraction, X-ray spectroscopy, scanning electron microscopy and steady-state and time-resolved photoluminescence (PL)-we reveal the two NC types to fundamentally differ. While the cube-shaped NCs exhibit properties aligning with that of bulk FAPbBr3, the nanorods exhibit a two-phase microstructure and the coexistence of both a typical cubic perovskite structure alongside the formation of a new low-symmetry monoclinic phase (P2/m). Further, the two-phase nanorods display a bright dual PL emission (peaks centered near 490 nm and 530 nm) and complex luminescence dynamics, properties characteristic of quasi-2D perovskites. The two phase nanorods generation can be assigned to the proton exchange in the presence of excess of FA + during the synthesis.

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An electrochemical biosensing platform for serum autoantibodies (AAbs) detection is reported in this work, exploiting for the first time six Alzheimer's disease (AD)-specific phage-derived and frameshift aberrant HaloTag peptides as receptors, immobilized on magnetic microbeads (MBs) surface and captured on disposable electrodes to perform amperometric detection. Operational analytical characteristics and clinical diagnostic ability of the bioplatform were probed in optimized key experimental conditions by analysing serum AAbs of AD patients and healthy subjects. The value of 100 % obtained for AUC, sensitivity, and selectivity from the all peptides combined ROC curve, indicate full AD-diagnostic capability of the methodology, which was further implemented, as proof of concept, in a POC multiplexing platform to detect the signature in a single test over clinically actionable times (1 h 15 min), opening great promise for the type of diagnosis and AD patients' monitoring follow-up currently pursued.Alzheimer's disease (AD) is the most common form of dementia in elderly age groups worldwide, with an estimated prevalence of 10-30 % and an average duration of about 10 years since the first clinical symptoms. [1,2] However, AD has long preclinical and prodromal stages which extend the disease for up to 20 years.

A dual immunosensor is reported for the simultaneous determination of two important immunity-related cytokines: BAFF (B cell activation factor) and APRIL (a proliferation-induced signal). Sandwich-type immunoassays with specific antibodies (cAbs) and a strategy for signal amplification based on labelling the detection antibodies (dAbs) with binary MoS2/MWCNTs nanostructures and using horseradish peroxidase (HRP) were implemented. Amperometric detection was carried out at screen-printed dual carbon electrodes (SPdCEs) through the hydroquinone HQ/H2O2 system. The developed dual immunosensor provided limit of detection (LOD) of 0.08 and 0.06 ng mL−1 for BAFF and APRIL, respectively, and proved to be useful for the determination of both cytokines in cancer cell lysates and serum samples from patients diagnosed with autoimmune diseases and cancer. The obtained results agreed with those found using ELISA methodologies. Graphical abstract