stability

Stability and dark hysteresis correlate in NiO-based perovskite solar cells

In perovskite solar cells (PSCs), the interfaces are a weak link with respect to degradation. Electrochemical reactivity of the perovskite’s halides has been reported for both molecular and polymeric hole selective layers (HSLs), and
here it is shown that also NiO brings about this decomposition mechanism. Employing NiO as an HSL in p–i–n PSCs with power conversion efficiency (PCE) of 16.8%, noncapacitive hysteresis is found in the dark, which is

Partially reversible photoinduced chemical changes in a mixed-ion perovskite material for solar cells

Metal halide perovskites have emerged as materials of high interest for solar energy-to-electricity conversion, and in particular, the use of mixed-ion structures has led to high power conversion efficiencies and improved stability. For this reason, it is important to develop means to obtain atomic level understanding of the photoinduced behavior of these materials including processes such as photoinduced phase separation and ion migration.

Stability of hydrogenated amorphous silicon diodes as thin film temperature sensors

This work reports on the characterization of stability of amorphous silicon diodes used as temperature sensors in lab-on-chip systems. We found that under constant forward current injection, the voltage drop over the diode changes depending on the values of current and injection time. The optimized operating conditions for practical applications have been established on the base of the obtained experimental data.

Stability of the stationary solutions of the Allen–Cahn equation with non-constant stiffness

We study the solutions of a generalized Allen–Cahn equation deduced from a Landau energy functional, endowed with a non-constant higher order stiffness. We assume the stiffness to be a positive function of the field and we discuss the stability of the stationary solutions proving both linear and local non-linear stability.

Simulated epidemics in 3D protein structures to detect functional properties

The outcome of an epidemic is closely related to the network of interactions between individuals. Likewise, protein functions depend on the 3D arrangement of their residues and the underlying energetic interaction network. Borrowing ideas from the theoretical framework that has been developed to address the spreading of real diseases, we study for the first time the diffusion of a fictitious epidemic inside the protein nonbonded interaction network, aiming to study network features and properties.

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