Studies on the fabrication of Ag/Hg₁Ba₂Ca₁Cu₂O₆₊ /CdSe heterostructures using the pulse electrodeposition technique

Abstract

Metal/superconductor/semiconductor (Ag/HgBaCaCuO/CdSe) heterostructures have been successfully fabricated using pulse-electrodeposition technique. The electrochemical parameters are optimized and diffusion free growth of CdSe onto Ag/HgBaCaCuO was obtained by employing under-potential deposition and by studying nucleation and growth mechanism during deposition. The heterostructures are characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM), scanning electron microscopy (SEM) studies and low temperature four probe electrical resistivity measurements. After the deposition of CdSe the critical transition temperature of HgBaCaCuO films was found be increased from 115 K with J c = 1.7 x 10 3 A/cm 2 to 117.2 K with J c = 1.91 x 10 3 A/cm 2 . When the heterostructure was irradiated with red He-Ne laser (2 mW), the T c was further enhanced to 120.3 K with J c = 3.7 x 10 3 A/cm 2 . This increase in superconducting parameters of HgBaCaCuO in Ag/ HgBaCaCuO/CdSe heterostructure has been explained at length in this paper.

Pseudocapacitive-battery-like behavior of cobalt manganese nickel sulfide (CoMnNiS) nanosheets grown on Ni-foam by electrodeposition for realizing high capacity

“…The maximum current is due to the overlap of diffusion zones formed around growing particles while the decreasing current behavior follows the Cottrell equation for planar diffusion. 5 The formation of an HIN of CoMnNiS (SEM micrograph) can be explained on the basis of the applied reduction potential and the additives 25 used in the electrodeposition process. By changing the reduction potential, the concentration of OH − ions at the electrode can be changed, which in turn influences pH of the solution as an increase in OH − will increase its pH.…”

“…In the former process nuclei are formed at the beginning of the electric pulse on active surface sites, while in the latter case simultaneous nuclei are formed during a continuous crystal growth process. [24][25][26][27][28] The behavior of the curve in region II, shown in the inset of Fig. 1(b) (i vs. t), corresponds to instantaneous nucleation of particles on Ni foam, thereby increasing the total surface area of the working electrode.…”

“…), showing the variation of Z and phase angle with frequency. A rise in phase angle to À66 25 ,. close to 90 , shows the capacitive behavior of the CoMnNiS electrode material.…”

Influence of Double-Pulse Electrodeposition Parameters on the Performance of Nickel/Nanodiamond Composite Coatings

“…Among them, DC electrodeposition and pulsed electrodeposition are more frequently used in production practice and have been widely used in precision instruments, electronic components, semiconductor nanoarray preparation, etc. [9][10][11][12][13][14][15][16]. The electrodeposition process has two processes: nucleation and crystal growth, which directly affect the microscopic morphology and properties of the deposit.…”