Advanced Materials Interfaces最新文献

There is an increasing interest in the exploration of non-Nickel cathode materials for steam electrolysis in solid oxide electrolysis cells (SOEC) for green hydrogen production with high Faradaic efficiencies. Ferrite-based ceramic materials have drawn a lot of attention in this regard due to their appreciable mixed ionic electronic conductivity. This work aims to explore a ferrite-based mixed ionic electronic conductor electrode for symmetrical SOEC that can contribute significantly to simplifying the manufacturing processes. A composite of silver (Ag) and A-site deficient lanthanum strontium cobalt ferrite ((La_0.60Sr_0.40)_0.95Co_0.20Fe_0.80O_3-x), is studied for steam electrolysis in a yttria stabilized zirconia electrolyte-supported symmetrical tubular solid oxide cell. A considerable current density of 250 mA cm⁻² is obtained at 1.5 V and 800 °C in a Helium-Steam atmosphere (50% humidified) with a corresponding polarization resistance as low as 0.15 Ω-cm². The polarization resistance is comparable to a number of electrodes reported in the literature for steam electrolysis. However, a 10% drop in current density is observed during the first 20 h of electrolysis at 1.5 V and 800 °C in a Helium-Steam atmosphere (50% humidified), but no further drop is encountered during the next 46 h of continuous operation.

p-Type Semiconductor

P-type oxide semiconducting materials processable at or slightly above room temperature are still rare. Notably, a 5 nm α-TeO₂ thin film represents such an electronically active material and can be gas phase deposited into a thin film transistor device architecture. Nature sometimes creates it as para tellurite polymorph in beautiful single crystals as found in the Bambollita mine, Moctezuma, Sonora, Mexico. More details can be found in article number 2301082 by Jörg J. Schneider and co-workers. Cover image by Dr. S. Okeil. We thank Borja Sainz de Baranda Graf for the image of the crystal.

Lead based bulk piezoelectric materials, e.g., PbZr_xTi_1-xO₃ (PZT), are widely used in electromechanical applications, sensors, and transducers, for which optimally performing thin films are needed. The results of a multi-domain Landau–Ginzberg-Devonshire model applicable to clamped ferroelectric thin films are used to predict the lattice symmetry and properties of clamped PZT thin films on different substrates. Guided by the thermal strain phase diagrams that are produced by this model, experimentally structural transitions are observed. These can be related to changes of the piezoelectric properties in PZT(x = 0.6) thin films that are grown on CaF₂, SrTiO₃ (STO) and 70% PbMg_1/3Nb_2/3O₃-30% PbTiO₃ (PMN-PT) substrates by pulsed laser deposition. Through temperature en field dependent in situ X-ray reciprocal space mapping (RSMs) and piezoelectric force microscopy (PFM), the low symmetry monoclinic phase and polarization rotation are observed in the film on STO and can be linked to the measured enhanced properties. The study identifies a monoclinic -rhombohedral M_C-M_A-R crystal symmetry path as the polarization rotation mechanism. The films on CaF₂ and PMN-PT remain in the same symmetry phase up to the ferroelectric-paraelectric phase transition, as predicted. These results support the validity of the multi-domain model which provides the possibility to predict the behavior of clamped, piezoelectric PZT thin films, and design films with enhanced properties.