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Proton-conducting oxides are potential materials for electrochemical devices such as fuel cells, hydrogen pumps, hydrogen sensors, and the tritium purification and recovery system in nuclear fusion reactors. The hydrogen concentration in oxide materials is important, but its precise measurement is difficult. In this study, thermal desorption spectroscopy (TDS) was used to investigate hydrogen dissolution and release behavior in three zirconates, BaZr 0.9 Y 0.1 O 3-α (BZY), BaZr 0.955 Y 0.03 Co 0.015 O 3-α (BZYC), and CaZr 0.9 In 0.1 O 2.95 (CZI) in the temperature range of 673–1273 K using deuterium (D 2) (1.33 kPa) and heavy water (D 2 O) (2.8 kPa, saturated pressure at room temperature). To compare the experimental results of the D 2 and D 2 O desorption profiles derived by TDS analysis, the simulation code of the tritium migration analysis program, version 4 (TMAP4) was employed. From TDS measurement, a similar trend of temperature-dependent hydrogen solubility was obtained for all samples compared to the literature data of HT- and DTO-exposed samples using a tritium imaging plate (TIP) method. A higher amount of hydrogen was dissolved in both BZY and BZYC under D 2 O exposure at 873 K, and the highest amount was found for BZYC. In most of the cases, the hydrogen diffusivities calculated by TMAP4 were higher than the experimental values, because oxygen is not considered a diffusion species in TMAP4. [Display omitted] • H- dissolution, release, solubility, and diffusivity behavior of BZY, BZYC, & CZI were investigated using D 2 & D 2 O by TDS method. • TDS results are compared with the previously reported TIP data. • TDS results are also compared with the simulation results of TMAP4. • Hydrogen diffusivities calculated by TMAP4 were higher than the experimental values. [ABSTRACT FROM AUTHOR]

• Conductivity of BZY and BZYC was investigated in six H-atmospheres including D 2 and D 2 O. • Cobalt not only improves the sinterability but also improves the conductivity at 500–800 °C. • Isotopic dependency was confirmed both in the dry and wet hydrogen atmospheres. [Display omitted] Among various perovskite proton conducting oxides, Y-doped BaZrO 3 perovskite is a promising material for electrochemical hydrogen devices due to its good chemical stability and higher proton conductivity at higher operating temperatures like 500–800 °C. For the practical application of the functional BaZrO 3 proton conductors in electrochemical hydrogen devices like tritium purification and recovery systems in a nuclear fusion reactor (where deuterium and tritium isotopes are utilized as fuel), it's necessary to understand the isotopic effect of proton conductivity. To understand the isotopic effect of proton conductivity in the barium zirconates, in this study, the proton conductivities in the Ar, (Ar + 4% H 2), (Ar + 4% D 2), (Ar + H 2 O), (Ar + D 2 O), and O 2 atmospheres were measured for two different compositions: BaZr 0.9 Y 0.1 O 2.95 (BZY), and BaZr 0.955 Y 0.03 Co 0.015 O 2.97 (BZYC) in the temperature range from 500 °C to 1000 °C. By comparing the obtained results, a significant difference in sinterability, conductivity, and the isotopic effect was observed due to the co-doping of the Co element in the BaZr 1−x Y x O 3-α proton conductor. [ABSTRACT FROM AUTHOR]

Polymer blend electrolytes based on poly(vinyl alcohol) (PVA) and sodium alginate (NaAlg) were prepared using the solution casting method. These electrolytes were doped with varying amounts of ammonium bromide (NH 4 Br). The compatibility of NH 4 Br with PVA:NaAlg polymers was examined through X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) studies. The FTIR assessment confirmed the formation of a complex between PVA:NaAlg and the added salt, as evidenced by modifications and reductions in the intensity of FTIR bands related to functional groups. The conductivity and dielectric behavior of the samples were analyzed using AC impedance spectroscopy. The sample with 20 wt% of added salt exhibited a higher ionic conductivity of 1.661×10−5 Scm−1. Activation energy and relaxation time were estimated, and dielectric studies revealed a non-Debye nature. The conduction mechanism was best described by the correlated overlapping large polaron tunneling model (OLPT). The highest conducting sample was found to be suitable for electrochemical devices, as demonstrated by transference number (TNM), cyclic volumetric (CV), and linear sweep voltammetry (LSV) analyses. This high-conductivity sample can be employed in electrochemical devices such as EDLC. The cyclic voltammetry (CV) curve exhibited a nearly rectangular shape with non-faradaic peaks. GCD(Galvanostatic charge-discharge) analysis yielded specific capacitance, power density, and energy density values of 125.01 Fg−1 , 1037 WKg−1, and 14.06 WhKg−1 respectively. These results indicate that polymer electrolytes show great promise as electrolytes in proton-conducting electrochemical devices. [Display omitted] • Solid polymer electrolytes including PVA blend NaAlg and concentrated NH 4 Br electrolytes were synthesized. • Ionic conductivity and stability are higher in solid polymer electrolytes. • Transference number reveals the inter-ion interactions that explain the high proton transport. [ABSTRACT FROM AUTHOR]

Carbon-based nanocomposites (NCs) attracted much attention in heterogeneous catalysis to remove organic dyes. Herein, a novel low-cost green approach was utilized to design a reduced graphene oxide (rGO) impregnated with Sn or Ag nanoparticles (NPs) using ginger extract as a green reducing agent. The synthesized NCs were characterized utilizing X-ray diffraction (XRD), Fourier transformation infrared (FTIR), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), Raman spectroscopy, and thermal gravimetric analysis (TGA). The synthesized NCs were assessed for their catalytic reduction activity towards methylene blue (MB) dye. XRD displayed the characteristic peaks of Sn- and Ag-NPs and the reduction of GO, referring to successful NC formation. FTIR and Raman confirmed the reduction of GO and the incorporation of Sn and Ag-NPs into the GO surfaces. TEM results proved that either Sn- or Ag-NPs was uniformly dispersed on rGO sheets with average sizes of 4.129 and 7.293 nm, respectively. EDX spectra of Sn@rGO- and Ag@rGO-NCs revealed the presence of C, O, Sn, and Ag. TGA confirmed the increased thermal stability of the NCs as compared to GO. Ag@rGO-NC exhibited stronger catalytic MB reduction (97% after 10 min) than Sn@rGO-NC (80% after 20 min). To the best of our knowledge, this is the first time Sn@rGO-NC has been designed for MB catalytic reduction, which gives rise to its promising capacity for future catalytic applications. • Sn@rGO and Ag@Rgo novel green composites were produced. • The efficiency of the catalytic dye reduction of the produced composites was estimated. • The reduction efficiency of 80% within 20 min for Sn@rGO-NC was observed. • The reduction efficiency of 97% within 10 min for Ag@rGO-NC was observed. • Chemical stability and high efficiency make it as candidates for the reduction of organic dyes. [ABSTRACT FROM AUTHOR]

Although perovskite solar cells (PSCs) have shown considerable advancement in recent years, their extensive usage is hindered by the major challenge of ensuring long-term stability. However, the enhanced stability of 2D-structure Dion-Jacobson (DJ) phase halide perovskites makes them a promising alternative to the traditional 3D perovskites, suggesting potential for broader application. In this numerical simulation, bulky organic ammonium spacer pentamethylenediamine (PeDA) was incorporated into DJ perovskite films with four different layer numbers (n = 3, 4, 5, and 6), which correspond to PeDAMA 2 Pb 3 I 10 , PeDAMA 3 Pb 4 I 13 , PeDAMA 4 Pb 5 I 16 , and PeDAMA 5 Pb 6 I 19 , respectively. Various parameters were adjusted to assess their impact on device performance. A current density–voltage (J-V) characterization was conducted for each value of n to compare their efficiencies. The number of layers was found to significantly influence efficiency, with the highest performance achieved at n = 6, resulting in an open-circuit voltage (V OC) of 1.27 V, a short-circuit current density (J SC) of 22.83 mA/cm2, a power conversion efficiency (PCE) of 21.17%, and a fill factor (FF) of 72.72%. These results demonstrate the potential of DJ perovskite solar cells with PeDA spacers as stable and efficient alternatives for photovoltaic applications. • Bulky organic ammonium spacer was incorporated into 2D-DJ perovskites with four different layer numbers. • DJ perovskite solar cells were simulated and optimized using SCAPS tool. • The number of layers significantly influenced the efficiency, with the highest performance achieved at n = 6. [ABSTRACT FROM AUTHOR]