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Supercapacitors are a promising candidate in applications that necessitate high electrochemical stability and storage energy. In this study, NiCo 2 O 4 nanosheets were prepared hydrothermally on an ITO substrate and investigated to be utilized as supercapacitor electrodes. The morphology of NiCo 2 O 4 nanosheets was examined by scanning electron microscopy (SEM ) and atomic force microscopy (AFM ). The SEM results showed a 3D-flower-like nanostructure with interconnected nanosheets which was confirmed by the AFM results. However, X-ray fluorescence (XRF) results showed that the as-prepared sample has stoichiometry of Nickle (1) : Cobalt (2) . The electrochemical measurements of the as-prepared NiCo 2 O 4 supercapacitor electrode such as cyclic voltammetry (CV ) and galvanostatic charge/discharge (GCD ) studies were done in a two-electrode system with 1.0 M KOH and 1.0 M H 2 SO 4 . CV curves showed quasi-rectangular shape and high electrochemical stability in KOH and H2SO4 electrolyte solutions. In addition, the integral areas of CV curves for both electrolytes are almost identical, indicating efficient charge transfer and ion transport at the electrode/electrolyte interface. Electrochemical impedance spectroscopy (EIS ) curves of KOH and H 2 SO 4 electrolyte revealed a significant difference. This difference indicates that, the charge transfer in H 2 SO 4 electrolyte is faster than charge transfer in KOH , resulting in a linear behavior of the EIS curve. A fabricated hybrid asymmetric supercapacitor (SC ) composed of NiCo 2 O 4 / ITO anode and graphite/ITO cathode delivered a specific capacity of around 235 F / g in KOH solution and 723 F / g in H 2 SO 4 electrolyte at 10 mV/s scan rate. The superior electrochemical performances could be attributed to the large surface area that facilitates charge transfer at the electrode/electrolyte interface. [ABSTRACT FROM AUTHOR]

We report on the photocatalytic degradation activity of methylene blue (MB) using Cellulose acetate (CA) membranes embedded by metal oxide nanoparticles (NPs). Titanium dioxide and Cerium dioxide (TiO2 and CeO2) and their nanocomposites are used as nanofillers in CA membranes to enhance photocatalytic activity. The casted nanocomposite membranes are synthesized using the phase inversion method and characterized using X-ray diffraction, X-ray fluorescence, scanning electron microscopy, Fourier-transform infrared spectroscopy, and UV–Vis to investigate structural, surface morphological, elemental content, and the optical properties. In particular, surface morphological and optical results are analyzed to elucidate a deeper understanding of porosity and photocatalytic activity via the degradation of the MB dye. The as-prepared CA–NP membranes are tested for photocatalytic degradation of MB by exposing the membrane/MB dye combination to UV illumination for different exposure times. Results reveal that CA–TiO2 membrane exhibits the smallest nanopore size, the most efficient exciton separation, and the largest surface area as compared with CA–CeO2 and CA–TiO2–CeO2-casted membranes. Consequently, CA–TiO2 membrane shows a good cyclic photocatalytic degradation activity (about 64%). Furthermore, the obtained MB degradation activity follows the increasing trend: CA–TiO2 membrane (Energy gap E g = 3.26 eV , Absorption activity A % = 64 % ) > CA–TiO2–CeO2 membrane ( E g = 3.33 eV , A % = 15 % ) > CA–CeO2 ( E g = 3.4 eV , A % = 7 % ) that is directly correlated with the values of the E g of the NP component of the membranes, the high porosity, and large surface area of the membrane. This suggests the synergetic use of the two metal oxides in potential applications of the photocatalytic degradation of MB and other organic pollutants for water treatment. [ABSTRACT FROM AUTHOR]

Elastic electron–proton scattering (e–p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, rp. In 2010, a new method using muonic hydrogen atoms1 found a substantial discrepancy compared with previous results2, which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen3,4. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e–p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e–p experiments and enabled measurements at very small forward-scattering angles. Our result, rp = 0.831 ± 0.007stat ± 0.012syst femtometres, is smaller than the most recent high-precision e–p measurement5 and 2.7 standard deviations smaller than the average of all e–p experimental results6. The smaller rp we have now measured supports the value found by two previous muonic hydrogen experiments1,7. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant8—one of the most accurately evaluated fundamental constants in physics. A magnetic-spectrometer-free method for electron–proton scattering data reveals a proton charge radius 2.7 standard deviations smaller than the currently accepted value from electron–proton scattering, yet consistent with other recent experiments. [ABSTRACT FROM AUTHOR]