Layered double hydroxides (LDHs) are an emergent class of biocompatible inorganic lamellar nanomaterials that have attracted significant research interest owing to their high surface-to-volume ratio, the capability to accumulate specific molecules, and the timely release to targets. Their unique properties have been employed for applications in organic catalysis, photocatalysis, sensors, drug delivery, and cell biology. Given the widespread contemporary interest in these topics, time-to-time it urges to review the recent progresses. This review aims to summarize the most recent cutting-edge reports appearing in the last years. It firstly focuses on the application of LDHs as catalysts in relevant chemical reactions and as photocatalysts for organic molecule degradation, water splitting reaction, CO₂ conversion, and reduction. Subsequently, the emerging role of these materials in biological applications is discussed, specifically focusing on their use as biosensors, DNA, RNA, and drug delivery, finally elucidating their suitability as contrast agents and for cellular differentiation. Concluding remarks and future prospects deal with future applications of LDHs, encouraging researches in better understanding the fundamental mechanisms involved in catalytic and photocatalytic processes, and the molecular pathways that are activated by the interaction of LDHs with cells in terms of both uptake mechanisms and nanotoxicology effects.

Recently, solid state photovoltaic Schottky diodes, able to detect ionizing radiation, in particular, x-ray and ultraviolet radiation, have been developed at the University of Rome “Tor Vergata.” We report on a physical and electrical properties analysis of the device and a detailed study of its detection capabilities as determined by its electrical properties. The design of the device is based on a metal/nominally intrinsic/p-type diamond layered structure obtained by microwave plasma chemical vapor deposition of homoepitaxial single crystal diamond followed by thermal evaporation of a metallic contact. The device can operate in an unbiased mode by using the built-in potential arising from the electrode-diamond junction. We compare the expected response of the device to photons of various energies calculated through Monte Carlo simulation with experimental data collected in a well controlled experimental setup i.e., monochromatic high flux x-ray beams from 6 to 20 keV, available at the Diamond Light Source synchrotron in Harwell (U.K.).

Ion stopping in warm dense matter is a process of fundamental importance for the understanding of the properties of dense plasmas, the realization and the interpretation of experiments involving ion-beam-heated warm dense matter samples, and for inertial confinement fusion research. The theoretical description of the ion stopping power in warm dense matter is difficult notably due to electron coupling and degeneracy, and measurements are still largely missing. In particular, the low-velocity stopping range, that features the largest modelling uncertainties, remains virtually unexplored. Here, we report proton energy-loss measurements in warm dense plasma at unprecedented low projectile velocities. Our energy-loss data, combined with a precise target characterization based on plasma-emission measurements using two independent spectroscopy diagnostics, demonstrate a significant deviation of the stopping power from classical models in this regime. In particular, we show that our results are in closest agreement with recent first-principles simulations based on time-dependent density functional theory.

Recently, a compact solid-state neutron detector capable of simultaneously detecting thermal and fast neutrons was proposed [M. Marinelli et al., Appl. Phys. Lett. 89, 143509 (2006)]. Its design is based on a $p$ -type/intrinsic/metal layered structure obtained by Microwave Plasma Chemical Vapor Deposition (CVD) of homoepitaxial diamond followed by thermal evaporation of an Al contact and a ${}^6\text{L}\text{iF}$ converting layer. Fast neutrons are directly detected in the CVD diamond bulk, since they have enough energy to produce the ${}^{12}\text{C}\left(n,\alpha \right){}^9\text{B}\text{e}$ reaction in diamond. Thermal neutrons are instead converted into charged particles in the ${}^6\text{L}\text{iF}$ layer through the ${}^6\text{L}\text{i}\left(n,\alpha \right)T$ nuclear reaction. These charged particles are then detected in the diamond layer. The thickness of the ${}^6\text{L}\text{iF}$ converting layer and the CVD diamond sensing layer affect the counting efficiency and energy resolution of the detector both for low- (thermal) and high-energy neutrons. An analysis is carried out on the dynamics of the ${}^6\text{L}\text{i}\left(n,\alpha \right)T$ and the ${}^{12}\text{C}\left(n,\alpha \right){}^9\text{B}\text{e}$ reactions products, and the distribution of the energy released inside the sensitive layer is calculated. The detector counting efficiency and energy resolution were accordingly derived as a function of the thickness of the ${}^6\text{L}\text{iF}$ and CVD diamond layers, both for thermal and fast neutrons, thus allowing us to choose the optimum detector design for any particular application. Comparison with experimental results is also reported.

Fabrication reproducibility and high performance reliability were obtained in fissile-material-free thermal neutron detectors based on chemical vapor deposited diamond in a multilayered $p$ -type/intrinsic/metal design. Under $\alpha$ particle irradiation, all the detectors (more than ten) have shown 100% charge collection efficiency and approximately 1.5% energy resolution. A ${}^6\mathrm{Li}\mathrm{F}$ layer was deposited on the detector surface as converting material for thermal neutrons through the ${}^6\mathrm{Li}(n,\alpha )\mathrm{T}$ nuclear reaction. Both the $2.73\mathrm{MeV}$ tritium and the $2.06\mathrm{MeV}$ $\alpha$ peaks are detected and clearly resolved. Stable performance and excellent linear behavior of the count rate versus the incident neutron flux were observed.