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The present work investigates the NO2 sensing properties of acceptor-doped ferrite perovskite nanostructures. The Sr-doped BiFeO3 nanostructures were synthesized by a salt precursor-based modified pechini method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The synthesized materials were drop coated to fabricate chemoresistive gas sensors, delivering a maximum sensitivity of 5.2 towards 2 ppm NO2 at 260 degrees C. The recorded values of response and recovery time are 95 s and 280 s, respectively. The sensor based on Bi0.8Sr0.2FeO3-delta (BSFO) that was operated was shown to have a LOD (limit of detection) as low as 200 ppb. The sensor proved to be promising for repeatability and selectivity measurements, indicating that the Sr doping Bismuth ferrite could be a potentially competitive material for sensing applications. A relevant gas-sensing mechanism is also proposed based on the surface adsorption and reaction behavior of the material.

All-solid-state Li-metal batteries (ASSLBs) are highly desirable, due to their inherent safety and high energy density; however, the irregular and uncontrolled growth of Li filaments is detrimental to interfacial stability and safety. Herein, we report on the incorporation of piezo-/ferroelectric BaTiO 3 (BTO) nanofibers into solid electrolytes and determination of electric-field distribution due to BTO inclusion that effectively regulates the nucleation and growth of Li dendrites. Theoretical simulations predict that the piezoelectric effect of BTO embedded in solid electrolyte reduces the driving force of dendrite growth at high curvatures, while its ferroelectricity reduces the overpotential, which helps to regularize Li deposition and Li + flux. Polarization reversal of soft solid electrolytes was identified, confirming a regular deposition and morphology alteration of Li. As expected, the ASSLBs operating with LiFePO 4 /Li and poly(ethylene oxide) (PEO)/garnet solid electrolyte containing 10% BTO additive showed a steady and long cycle life with a reversible capacity of 103.2 mAh g −1 over 500 cycles at 1 C. Furthermore, the comparable cyclability and flexibility of the scalable pouch cells prepared and the successful validation in the sulfide electrolytes, demonstrating its universal and promising application for the integration of Li metal anodes in solid-state batteries.

Electron transporting layers facilitating electron extraction and suppressing hole recombination at the cathode are crucial components in any thin-film solar cell geometry, including that of metal-halide perovskite solar cells. Amorphous tantalum oxide (Ta2O5) deposited by spin coating was explored as an electron transport material for perovskite solar cells, achieving power conversion efficiency (PCE) up to ~14%. Ultraviolet photoelectron spectroscopy (UPS) measurements revealed that the extraction of photogenerated electrons is facilitated due to proper alignment of bandgap energies. Steady-state photoluminescence spectroscopy (PL) verified efficient charge transport from perovskite absorber film to thin Ta2O5 layer. Our findings suggest that tantalum oxide as an n-type semiconductor with a calculated carrier density of ~7 x 10(18)/cm(3) in amorphous Ta2O5 films, is a potentially competitive candidate for an electron transport material in perovskite solar cells.

For achieving a sustainable energy future, energy consumption through renewable sources needs to be maximized and greenhouse emissions should be radically reduced. Automotive exhausts sharing the largest global NOX emissions must meet regulated standards by after-treatment systems (ATS) equipped with smart electronic feedback loops through on-board NOX monitoring. Herein, we demonstrate an efficient (Dy, W) co-doped Bi2O3-based electrochemical sensing architecture equipped with Ln(2)NiMnO(6) double perovskite oxides (DPOs) as electrode materials for selective nitric oxides (NO) detection. The sensor configuration facilitates operation in a wide temperature range (325 & DEG;C-500 & DEG;C) with high sensitivity of 50 mV/decade, a response time below 60 sec. and detection abilities as low as 200 ppb. While investigating the impact of rare-Earth cations, a predominant Ni3+-O-Mn3+ interaction and acquisition of optimal e(g) (1) electron configuration of transition metal atoms in La2NiMnO6 was found responsible for improved electrocatalytic and redox chemical activity that substantiates the sensing behavior. The study carefully scrutinizes the sensing mechanism to abide by the mixed-potential model. Moreover, the durability assessed over a month of operation supported the applicability of presented sensing elements in on-board NOX monitoring systems.