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Metal oxide nanoparticles and their composites with conducting polymers, specifically Polyaniline (PANI) were utilized for fabricating nanoscale supercapacitor (SC) electrode materials. In the present study, we have synthesized pristine Pr 2 O 3 , NiO, Co 3 O 4 nanoparticles, binary PANI-Pr 2 O 3 , PANI-NiO, PANI-Co 3 O 4 , ternary Pr 2 O 3 –NiO–Co 3 O 4 , and quaternary PANI-Pr 2 O 3 –NiO–Co 3 O 4 spherical core-shell nanocomposite using co-precipitation and ultra-sonication methods. The grown samples were characterized with different analytical techniques. The XRD pattern revealed that the as-synthesized products were crystalline with Pr 2 O 3 hexagonal phase, NiO cubic phase, and Co 3 O 4 cubic phase in pure and nanocomposites. The Williamson-Hall, Scherrer, and size-strain plot methods were employed to study the crystalline development and contribution of micro-strain. FTIR pattern exhibited the metal-oxygen and PANI bond vibrations. FE-SEM images shown the spherical core-shell shape morphology of quaternary nanocomposite. EDX evident the presence of praseodymium, cobalt, and nickel in synthesized samples. UV–vis spectroscopy confirmed the absorption in the visible region. The IV graphs showed a higher conductivity of quaternary nanocomposite. The cyclic voltammetry results revealed that the quaternary nanocomposite has a higher specific capacitance 500 Fg-1 as compared to binary nanocomposites 134 F g−1 (PANI-Pr 2 O 3), 143 F g−1 (PANI-Co 3 O 4), 256 F g−1 (PANI-NiO), and PANI (90.8 F g−1) at a scan rate of 5 m Vs−1. The GCD results also showed that the quaternary nanocomposite has a higher specific capacitance of 905 F g−1 at current density 1 A g−1 with maximum energy density and power density of 87.99 kWhkg-1 and 2.6 k W kg−1 , respectively. The EIS curve also confirmed that the quaternary nanocomposite has a lower polarization resistance (R p) and solution resistance (R s). The higher capacitance of quaternary nanocomposite can facilitate ion transfer, and the formation of its core-shell structure flourish to enhance surface-dependent electrochemical properties. Furthermore, this study gives a novel research idea to manufacture electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Nowadays, environmental pollution due to discharge of organic pollutants from food, textile, and pharmaceutical industries into clean water and development of contagious diseases due to pathogenic organisms provide impetus to material researcher to fabricate novel design for efficient photocatalyst and antimicrobial agents. In this regard, designing a core-shell heterojunction catalyst based on metal oxides is considered an auspicious approach. In present study, combating the problems of singular oxides, core-shell PANI-CeO 2 -Fe 2 O 3 –NiO nanocomposite (PCFN) and CeO 2 –Fe 2 O 3 –NiO nanocomposite (CFN) was synthesized through sol-gel and oxidative polymerization route with cetyletrimethylammonium bromide (CTAB) as surfactant. The XRD, FTIR, and Raman confirmed the formation of nanocomposites with core-shell morphology composed of PANI (shell) and oxides (Core) in PCFN with a particle size of 52 nm (TEM). Surprisingly, PCFN has lower band gap, e−/h+ recombination, and larger charge transfer character than CFN. The decomposition test using MB and MO dyes showed that PCFN degraded 99%, 98%, while CFN degraded only 73% and 54%, respectively, under 50 min sunlight illumination. The reusability was assessed up to 7th cycle for PCFN. The influence of operational parameters (catalyst dose, dye concentration, pH) was tested for PCFN. Further, the antimicrobial action against S. aureus (gram + ve), E. coli (gram -ve) were also tested. The supreme performance of PCFN has been credited to heterostructure dual Z-scheme formation and core-shell morphology supported with PANI, which suppresses the e−/h+ recombination process by promoting their separation. The present finding indicated that the PCFN is a promising modifier for bacterial disinfection and acts as a superb photocatalyst through core-shell formation with PANI support. • Synthesis of core-shell PANI-CeO 2 -Fe 2 O 3 –NiO nanocomposite via solution method. • Enhanced photodegradation of MB and MO dyes under natural sunlight. • The higher ability to inhibit the growth of S. aureus and E. coli bacterial strains. • Dual Z-scheme heterostructure formation leads to better charge transfer. • Efficient catalyst for dye pollutant elimination and bacterial disinfection. [ABSTRACT FROM AUTHOR]

• Direct dual Z-scheme TiO-WO 3 -CeO 2 heterostructured nanocomposite successfully synthesized by co-precipitation route. • The nanocomposite TiO-WO 3 -CeO 2 showed boosted photocatalytic activity towards different pollutants. • Systematic investigations confirmed the superior charge separation by direct dual Z-scheme. • Enhanced antibacterial activity of nanocomposite against various pathogenic bacterial strain. • The higher super-capacitive behaviour of nanocomposite. [Display omitted] Direct dual Z-scheme heterostructured nanocomposite TiO 2 -WO 3 -CeO 2 (NC) and pristine metal oxides nanostructures (NSs) were fabricated using a facile co-precipitation route. XRD, FTIR, and Raman data have confirmed the formation of NSs and NC. FESEM images showed quasi-mesoporous morphology of as-grown nanocomposite. EDX analysis confirmed the existence of titanium (Ti), cerium (Ce), and tungsten (W) in grown NC. The energy bandgap of NC was narrow 2.45 eV as compared to NSs. The higher electrical conductivity and lower recombination rate of NC were observed in IV and PL analysis. The photodegradation efficiency of NC was recorded 99.8% after 60 min under sunlight radiation against methylene blue (MB), which was significantly higher than NSs. NC catalyst has shown excellent photodegradation against other organic pollutants and has superior recyclability up to 7th cycle toward MB dye with a ~ 6% deficit in photodegradation efficiency. The antimicrobial activity results indicated the higher inhibition ability of NC against E. coli , K. pneumoniae , S. aureus , P. Vulgaris , and P. aeruginosa with maximum inhibition zone diameter 25, 29, 26, 28, and 27 mm, respectively. The electrochemical tests including CV, EIS, and GCD exhibited the superior capacitive behaviour of NC. These results demonstrate that grown NC is an efficient material for electrochemical devices, water purification, and biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract: Tin oxide coated molybdenum oxide nanowires (SnO2/MoO3) are synthesized by a combination of hydrothermal and wet chemical routes. The electrochemical capacitance properties of the SnO2/MoO3 core shell composite nanowires are measured by cyclic voltammetry (CV) and galvanostatic charge–discharge method in 1M Na2SO4 aqueous solutions. The results showed that specific capacitance of SnO2/MoO3 core shell composite nanowires is 295Fg−1, which is much higher than the specific capacitance of pure individual MoO3 (69Fg−1) and SnO2 (96.6Fg−1). Moreover the synthesized core shell composite nanowires has also exhibited excellent long-term cycling stability (only 3% loss of its initial specific capacitance after 1000 cycles) which may lead to its multifarious usage in high-performance energy storage devices for future potential applications. [Copyright &y& Elsevier]

Binary NiO-Fe2O3, NiO-CdO nanocomposites, and ternary NiO-Fe2O3-CdO nanocomposite are synthesized using facile co-precipitation method, and their photocatalytic and antibacterial properties are studied. The as-obtained products are characterized using different analytical techniques. The microstructural parameters were calculated using X-ray diffraction data. UV–vis spectra technique was used to calculate the bandgap and listed 3.1, 2.7, and 2.5 eV for NiO-Fe2O3, NiO-CdO, and NiO-Fe2O3-CdO nanocomposite, respectively. The photocatalytic activity of as-obtained products was tested under visible light against methylene blue (MB) dye. The NiO-Fe2O3-CdO nanocomposite has shown higher degradation efficiency as compared to binary nanocomposites and revealed improve electron–hole separation efficiency. The photocatalytic performance of NiO-Fe2O3-CdO nanocomposite was also tested for other synthetic dyes such as rhodamine-B (RhB), methyl orange (MO), and cresol red (CR). The antibacterial performance of grown products was tested against E. coli bacteria. The ternary NiO-Fe2O3-CdO nanocomposite has shown higher antibacterial activity than binary NiO-Fe2O3 and NiO-CdO nanocomposites. [ABSTRACT FROM AUTHOR]