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The financial well-being (FWB) of individuals is a topic that is becoming increasingly important across a multitude of disciplines. In this study, we use the 2016 National Financial Well-Being Survey administered by the Consumer Financial Protection Bureau to assess the determinants of an individual's FWB. We identify 144 potential covariates that could explain variation in the FWB score of individuals. The statistical methodology of choice is the Bayesian LASSO, which is a covariate selection algorithm that also allows for the importance ranking of covariates. Out of the 144 potential covariates, we find that 26 have 95% credible intervals that do not contain zero. Broadly speaking, the results show that objective measures of financial competency and psychological and sociological factors contribute the bulk of the explanatory power that help explain an individual's FWB score., INTRODUCTION Financial well-being (FWB), often known as financial freedom, is the ability to make decisions that allow individuals to live a fulfilling life while still being able to satisfy their [...]

Environmental water pollution caused by hexavalent chromium (Cr(VI)) is a threat to living beings due to its carcinogenic nature. Herein, we report the synthesis of a highly fluorescent water-soluble conjugated polyelectrolyte PPMI and its application as a fluorescence sensor to monitor traces of carcinogenic Cr(VI) ions in water. PPMI was synthesized via the oxidative polymerization method followed by post-polymer functionalization. Fluorescent PPMI exhibited a photoluminescence quantum yield of 23.87 and displayed a rapid, very selective, and sensitive turn-off fluorescence signal in response to Cr(VI), with a significantly high quenching constant of 1.32 × 106 M−1. The mechanism of sensing was found to be static quenching. The limit of detection of this highly accessible analytical method was found to be in nanomolar ranges, i.e. 0.85 nM. Additionally, sensing on solid platforms such as economical paper strips was successfully achieved, which is very challenging and highly recommended for any reliable, portable, and economical analytical method. [ABSTRACT FROM AUTHOR]

Sol-gel prepared homogeneous Ba1 − xPbxTiO3 ceramics reveal elongation along the c-axis and contraction along the a-axis, thereby increasing the tetragonality (c/a ratio) with Pb doping. Raman spectral shape changes with composition and hardening and softening of vibrational modes are discussed and correlated to the structure and oxygen content. A new differential mode (in BaTiO3) predicted theoretically between two A1 Raman modes is experimentally detected at ∼71 cm−1. Tetragonal to cubic phase transition temperature (Tc) increases linearly with an increase in Pb content. Hence, appropriate Pb addition enhances Tc and thereby retains ferroelectricity until it reaches a higher temperature in the ceramics. Ferroelectricity in the solid solution was confirmed to enhance with an increase in Pb content from field-dependent polarization measurements. With Pb content, more than 50%, ferroelectric properties of the ceramics degrade and the materials become lossy due to the presence of O-defects originating from Pb-loss. This work provides an insight into how two well-known ferroelectric properties can be mixed to enhance its properties. [ABSTRACT FROM AUTHOR]

ZnCo2O4 has been studied as an electrode material for supercapacitor applications because of its excellent redox activity. It is known that morphology plays an important role in deciding the electrochemical behavior of material through factors such as specific surface area and active surface states. Surfactant plays a significant role in determining the morphology and hence surface area of the material. Here, we present an extensive comparative study on the effect of two surfactants, urea and hexamethylenetetramine (HMTA), on the morphology of ZnCo2O4 and its impact on both supercapacitor and oxygen evolution reaction (OER) performance. Synthesis of ZnCo2O4 using urea yields urchin-like morphology, which exhibits a specific capacity of 94 mAh g−1 at 2 A g−1 , which is much higher than the 34 mAh g−1 achieved through hexagonal sheet-type morphology obtained from HMTA as a surfactant. We fabricated a coin cell with the urea-derived material, which shows an energy density of 19 W h kg−1, a power density of 4125 W kg−1 , and a Coulombic efficiency of 97%. Further, a comparative study of OER for both types of morphology yields a lower overpotential of 336 mV for urea-derived urchin morphology compared to 362 mV for the HMTA-based sample. Other electrochemical parameters, such as Tafel slope, double-layer capacitance, and turn-over frequency, are also evaluated for both types of morphology. The better overall performance of urea-based urchin-like morphology is attributed to higher specific surface area and oxygen vacancies, as confirmed through Brunauer–Emmett–Teller (BET) and x-ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

A systematic study on the effect of gallium (Ga) doping (0 ≤ x ≤ 0.10) on the structural phase transition and grain growth of TiO2 is reported here. X-ray diffraction spectroscopy and Raman spectroscopy confirm that Ga doping inhibits the phase transition. Activation energy increases from 125 kJ/mol (x = 0.00) to 300 kJ/mol (x = 0.10) upon Ga incorporation. X-ray photoelectron spectroscopy shows the presence of Ti3+/Ga3+ interstitials, substitution (Ti4+ by Ga3+), and oxygen vacancies in the samples. At lower doping (x ≤ 0.05), interstitials play a more significant role over substitution and oxygen vacancies, thereby resulting in a considerable lattice expansion. At higher doping (x ≥ 0.05), the effect of interstitials is compensated by both the effect of substitution and oxygen vacancies, thereby resulting in relatively lesser lattice expansion. Inhibition of the phase transition is the result of this lattice expansion. The crystallite size (anatase) and particle size (rutile) both are reduced due to Ga incorporation. It also modifies optical properties of pure TiO2 by increasing the bandgap (from 3.06 to 3.09 eV) and decreasing the Urbach energy (from 58.59 to 47.25 meV). This happens due to regularization of the lattice by the combined effect of substitution/interstitials and oxygen vacancies. [ABSTRACT FROM AUTHOR]

A systematic study on the effect of gallium (Ga) doping (0 ≤ x ≤ 0.10) on the structural phase transition and grain growth of TiO2 is reported here. X-ray diffraction spectroscopy and Raman spectroscopy confirm that Ga doping inhibits the phase transition. Activation energy increases from 125 kJ/mol (x = 0.00) to 300 kJ/mol (x = 0.10) upon Ga incorporation. X-ray photoelectron spectroscopy shows the presence of Ti3+/Ga3+ interstitials, substitution (Ti4+ by Ga3+), and oxygen vacancies in the samples. At lower doping (x ≤ 0.05), interstitials play a more significant role over substitution and oxygen vacancies, thereby resulting in a considerable lattice expansion. At higher doping (x ≥ 0.05), the effect of interstitials is compensated by both the effect of substitution and oxygen vacancies, thereby resulting in relatively lesser lattice expansion. Inhibition of the phase transition is the result of this lattice expansion. The crystallite size (anatase) and particle size (rutile) both are reduced due to Ga incorporation. It also modifies optical properties of pure TiO2 by increasing the bandgap (from 3.06 to 3.09 eV) and decreasing the Urbach energy (from 58.59 to 47.25 meV). This happens due to regularization of the lattice by the combined effect of substitution/interstitials and oxygen vacancies. [ABSTRACT FROM AUTHOR]

Designing a photocatalyst material with reduced recombination of photogenerated charges is one of the most important aspects of hydrogen generation through solar water splitting. Here, we report hydrogen generation using the TiO2/ultrathin g-C3N4 (U-g-CN) heterostructure fabricated using a unique in situ thermal exfoliation process. Multilayer g-CN is converted into U-g-CN having a high surface (∼190 m2/g) area by calcination at ∼550 °C through oxygen-induced exfoliation, which also forms a robust heterostructure with TiO2. In addition, the presence of g-CN also inhibits further growth of TiO2 nanoparticles, thereby retaining a high specific surface area. The presence of U-g-CN causes a redshift (∼0.13 eV) in the absorption edge of heterostructure compared to that of bare TiO2, which extends the light absorption capability. Addition of 40 wt. % of multilayer g-CN to TiO2 shows an enhanced H2 evolution rate, which is ∼15 times and ∼4 times higher compared to that of bare TiO2 and U-g-CN, respectively. Photoluminescence (PL) and time-resolved PL (TRPL) studies indicate a reduced recombination rate of photogenerated charge carriers with an increase in the average lifetime from 10.53 (TiO2) to 13.32 ns (TiO2/U-g-CN40). The interfacial charge transport characteristics studied through impedance spectroscopy reveal a reduced charge transfer resistance at the semiconductor–electrolyte interface, which facilitates faster charge separation due to the heterostructure formation. The band edge positions are estimated through flatband potential from the Mott–Schottky measurements and optical absorption data, indicating a type-II heterojunction. More light absorption and enhanced separation of photogenerated charges at the heterojunction interface lead to better photocatalytic H2 generation. [ABSTRACT FROM AUTHOR]