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This work reports the synthesis of β-cyclodextrin (β-CD)/cellulose (CA) nanofibers embedded with silver (Ag) and silver/iron (Ag/Fe) nanoparticles (NPs) via a benign process involving in situ electrospinning of the biopolymers with Ag and Fe salts. The electrospun nanocomposite fibers containing Ag+/Fe3+ ions were then subjected to UV photochemical reduction in the presence of water vapor under inert atmosphere to reduce the ions to zerovalent state. SEM and TEM revealed that the average diameter of the β-CD/CA nanofibers was 382.12 ± 30.09 nm and that the diameters of Ag and Ag/Fe NPs were 38.81 ± 8.21 nm and 56.29 ± 12.64 nm, respectively, after reduction. The XRD and EDS analysis confirmed the presence of the Ag and Fe NPs on the surface of the nanofibers. The effect of UV irradiation time on the reduction of the Ag+ and Fe3+ was studied by measuring the UV–vis absorbance of the reduced NPs. The biocidal effect of Ag and Ag/Fe was investigated using 12 different strains of bacteria. The Ag and Ag/Fe NPs embedded on the β-CD/CA nanofibers exhibited a strong biocidal effect on all of the bacteria strains.

A Ni-based metal–organic framework (Ni-MOF) has been synthesized using a microwave-assisted strategy and converted to nanostructured Ni/MOF-derived mesoporous carbon (Ni/MOFDC) by carbonization and acid treatment (AT-Ni/MOFDC). The materials are well characterized with Raman, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET), revealing that chemical etching confers on the AT-Ni/MOFDC-reduced average nanoparticle size (high surface area) and structural defects including oxygen vacancies. AT-Ni/MOFDC displays low series resistances and a higher specific capacity ( C s ) of 199 mAh g –1 compared to Ni/MOFDC (92 mAh g –1 ). This study shows that the storage mechanism of the Ni-based electrode as a battery-type energy storage (BTES) system can be controlled by both non-faradic and faradic processes and dependent on the sweep rate or current density. AT-Ni/MOFDC reveals mixed contributions at different rates: 75.2% faradic and 24.8% non-faradic contributions at 5 mV s –1 , and 34.1% faradic and 65.9% non-faradic at 50 mV s –1 . The full BTES device was assembled with AT-Ni/MOFDC as the cathode and acetylene black (AB) as the anode. Compared to recent literature, the AT-Ni/MOFDC//AB BTES device exhibits high energy (33 Wh kg –1 ) and high power (983 W kg –1 ) with excellent cycling performance (about 88% capacity retention over 2000 cycles). This new finding opens a window of opportunity for the rational designing of next-generation energy storage devices, supercapatteries, that combine the characteristics of batteries (high energy) and supercapacitors (high power).

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