ABSTRACT
It is common knowledge that the O2 evolution reaction (OER) is a crucial half-reaction in the electrolysis of water. However, it is currently difficult to create inexpensive OER electrode materials in a way that is efficient, simple, and environmentally friendly. In this research, metal oxy-hydroxides with numerous oxygen defects (M-OOHv) are created at surface of Cu foam (CF) using a unique, straightforward electro-oxidation reconstitution (ER) process. Different spectroscopic and microscopy methods are used to analyse the electrode characteristics of Al2Cu-MOF@M-OOHv-ER/CF; electrochemical measurements display a lower overpotential (η) of 366 mV @ 10 mA cm-2 and a Tafel slope of 95.2 mV dec-1 in 1.0 M KOH. X-Ray diffraction (XRD), scanning electron microscopy (SEM), and Raman studies confirm the phase transition of the metal-organic framework (MOF) to the M-OOH, which acts as the active site to boost the OER activity. Through spectroscopic and microscopic investigations, it is determined that the efficiency of bimetallic electrode materials and oxygen vacancies in the M-OOHv have an impact on the electron power density. The manufactured electrode material additionally showed good durability for 50 hours. As a result, the newly developed Al2Cu-MOF@M-OOHv-ER/CF nanomaterial has greater potential for both electrolysis of water and other energy storage equipment.
ABSTRACT
Pristine thermally evaporated nickel-(II)-tetraphenyl-21H,23H-porphyrin (NiTPP) thin films are amorphous, but after 4 and 8 h of UV illumination, the films become crystalline with preferred orientations of (112), (103) and (004) and crystallite sizes of (13, 18, 16) and (42, 31, 38) nm after 4 and 8 h, respectively. After UV illumination for 4 and 8 h, the NiTPP thin films are characterized by blueshifted absorption coefficients, increasing the optical and fundamental gap values and decreasing the dispersion parameter values. The dielectric properties display energy storage regions corresponding to the peak values of optical conductivity, which provides an elegant confirmation of the tailoring and tuning of band gaps, energy storage properties and optical conductivity by UV illumination time. Therefore, NiTPP films may be good candidates for environmental and energy storage applications.
ABSTRACT
Characterization of organic nickel-(II)-tetraphenyl-21H,23H-porphyrin films as a function of substrate type was performed for energy storage applications and consequently environmental enhancement. Nickel-(II)-tetraphenyl-21H,23H-porphyrin films show an amorphous phase. They have a crystallite size of 8-11 nm. Strain caused a shift of different humps' positions. The measured transmittance has high values within the range of 85-91%, and the absorption coefficient values were included within the high-absorption region. Both optical gap and fundamental gap, refractive index, carrier-concentration-to-effective-mass ratio and lattice dielectric constant were calculated, and they were found to be increased, except refractive index and lattice dielectric constant. The obtained data indicated that nickel-(II)-tetraphenyl-21H,23H-porphyrin films are a candidate for energy storage applications.