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Supercapattery is an energy storage device which shows high power and energy densities compared to supercapacitors and batteries. A simple and cost‐effective sol‐gel method was used to synthesize the aluminium‐doped cobalt oxide (Al‐Co3O4). The structural, morphological and composition analyses were investigated using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and X‐ray photoelectron spectroscopy (XPS). Further, Brunauer‐Emmett‐Teller (BET) calculations were performed, which showed an enhancement in surface area. The specific capacity of the Al‐doped sample was increased up to 708 C/g compared to the reference sample (Co3O4=420 C/g). A supercapattery device was designed by using the activated carbon as a negative electrode and the Al‐Co3O4 as the positive electrode in two electrode assemblies. The estimated value of the specific capacity of Al‐Co3O4 was 189 C/g. Furthermore, the obtained energy and power density values were 42 Wh/kg and 2080 W/kg, respectively. To investigate the stability, this device was subjected to 5000 charging/discharging cycles that maintained 90 % of its initial capacity. Our findings provide a foundation for improving the performance of energy storage devices. [ABSTRACT FROM AUTHOR]

Inverse perovskites are the counterparts to the largest family of crystalline perovskite materials and have attracted significant research interest because of their unconventional physical and chemical properties. Perovskite materials have been studied widely; however, less attention has been paid to their counterparts (inverse perovskites). In the present study, we report on the structural, electronic, elastic, mechanical, magnetic and thermodynamic properties of unexplored Rh-based XCRh3 (X = Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Zr, Nb, Mo, Tc, Ru, Pd, Ag) inverse perovskites. The first-principles density functional theory-based linearized augmented plane wave method as implemented in the Wien2k package with the generalized gradient approximation was employed for the investigation of the physical properties. The computed formation energies showed that the majority of these materials comparatively favor the ferromagnetic phase over the non-magnetic phase. Amongst the studied XCRh3, X = Ti-, V-, Cr-, Mn-, Zn- and Zr-based materials comprise negative formation energies confirming the energetic stability. All the compounds other than NbCRh3 and MoCRh3 were found mechanically stable. Spin-projected electronic properties of XCRh3 revealed the conducting features in both spin versions. The large magnetic moments per unit cell (> 3μB) of CrCRh3, MnCRh3, FeCRh3 and TcCRh3 were observed with dominant contribution from X-atoms. Mechanical anisotropy and other bulk mechanical parameters are elaborated and discussed in detail. The thermodynamic properties including specific heat capacity, thermal expansion coefficient and Debye temperature are scrutinized at different temperature and pressure ranges. [ABSTRACT FROM AUTHOR]

Cadmium ferrites belong to normal spinel ferrites, and they exhibit interesting electrical, magnetic, and optical properties. The pure and cerium-doped cadmium ferrites CdFe2−xCexO4 (x = 0.0, 0.125, 0.250, 0.375, 0.5) were synthesized by a chemical co-precipitating technique using sodium hydroxide as a co-precipitating agent. The structures and phase purity of fabricated nanomaterials were analyzed by X-ray diffraction (XRD). The crystallite size for all the prepared nanomaterials was in the range of 28–46 nm. The lattice constant and unit cell volume were found to decrease with the increasing concentration of Cerium, which was confirmed by the peak shift in the XRD pattern. The X-ray density for all nano ferrites increased with the enhancement of cerium composition. The resistivity of the nanomaterials has random behavior with the enhancement of cerium composition for a temperature, but the value of resistivity at x = 0.125 has the lowest value and at x = 0.375 has the highest value for almost all temperatures. For specific concentrations, a decreasing trend of resistivity of fabricated materials was found with an increment of temperature. The activation energies were also calculated, and it increased for x = 0.125 and then decreased for all the nanomaterials. For the confirmation of the M–O bonds, FTIR analysis of all the nano ferrites was also performed. The analysis shows a higher frequency absorption band in the range of 531.24–534.84 cm−1. This absorption band confirms that metal oxides are formed in all the synthesized nanoparticles. [ABSTRACT FROM AUTHOR]

Cadmium ferrites belong to normal spinel ferrites, and they exhibit interesting electrical, magnetic, and optical properties. The pure and cerium-doped cadmium ferrites CdFe2−xCexO4 (x = 0.0, 0.125, 0.250, 0.375, 0.5) were synthesized by a chemical co-precipitating technique using sodium hydroxide as a co-precipitating agent. The structures and phase purity of fabricated nanomaterials were analyzed by X-ray diffraction (XRD). The crystallite size for all the prepared nanomaterials was in the range of 28–46 nm. The lattice constant and unit cell volume were found to decrease with the increasing concentration of Cerium, which was confirmed by the peak shift in the XRD pattern. The X-ray density for all nano ferrites increased with the enhancement of cerium composition. The resistivity of the nanomaterials has random behavior with the enhancement of cerium composition for a temperature, but the value of resistivity at x = 0.125 has the lowest value and at x = 0.375 has the highest value for almost all temperatures. For specific concentrations, a decreasing trend of resistivity of fabricated materials was found with an increment of temperature. The activation energies were also calculated, and it increased for x = 0.125 and then decreased for all the nanomaterials. For the confirmation of the M–O bonds, FTIR analysis of all the nano ferrites was also performed. The analysis shows a higher frequency absorption band in the range of 531.24–534.84 cm−1. This absorption band confirms that metal oxides are formed in all the synthesized nanoparticles. [ABSTRACT FROM AUTHOR]

In this report, Mg(0.6)Zn(0.4)Fe2O4 (MZF) and CuxMg(0.6)Zn(0.4)Fe2O4 (CMZF) where (x = 0.2) were synthesized via sol–gel method. The composite of CuxMg(0.6)Zn(0.4)Fe2O4 with reduced graphene oxide (CuxMg(0.6)Zn(0.4)Fe2O4@rGO) was fabricated by wet chemical approach to get over the adverse impacts of toxic dyes and pathogenic bacterial strains. The rGO possesses high stability, larger surface area and an enhanced ability for electron transport during photocatalysis. X-ray diffraction, Scanning electron microscopy, Fourier transform infrared spectroscopy, Mott Schottky and UV–Visible spectroscopy were used to analyze the physiochemical properties of manufactured materials. Methylene blue (MB) and benzoic acid (BA) degradation was performed under the visible light of the Xenon lamp. The photocatalytic activity of MB exhibited degradation efficiency by MZF, CMZF, and CMZF@rGO was 16.67%, 42.72% and 76.19% respectively and degradation of BA by MZF, CMZF, and CMZF@rGO was 26.92%, 44.44% and 60.42% respectively. The composite (CMZF@rGO) exhibited the best degradation efficiency than bare and doped materials (MZF and CMZF) due to the greater surface area. As surface area increased, the e−/h+ pair recombination rate decreased. Therefore, the photocatalytic efficiency of the material enhanced. It is examined, CMZF@rGO has potential applications in the photocatalytic degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

The rapid recombination of charges of photogenerated electrons and holes severely limits single semiconductor photocatalytic applications. In this study, a simple and facile sol-gel approach was used to synthesize Ba 2- x Ho x Sr 2- y Ni y Fe 12 O 22 ( x = 0, 0.1 and y = 0, 0.5). The composite of holmium-nickel doped barium-strontium ferrite with MXene (Ba 1.9 Ho 0.1 Sr 1.5 Ni 0.5 Fe 12 O 22 @MXene) was synthesized by ultrasonication method. These synthesized samples were subsequently used to photodegrade rhodamine B (RhB) and pendimethalin under visible light illumination. The results of the experiments demonstrated that MXene, as a cocatalyst, considerably reduces the rate of recombination of charges and broadens absorption of visible light by providing increased surface functional groups to improve the photocatalytic activity of synthesized samples. MXene is thermally stable, have high electrical conductivity, have adjustable bandgap, and hydrophilic in nature. The optimized Ba 1.9 Ho 0.1 Sr 1.5 Ni 0.5 Fe 12 O 22 @MXene composite demonstrated an excellent photocatalytic rate by degrading 78.88% RhB and 75.59% pendimethalin in 140 minutes. Moreover, the scavenging experiment revealed that photogenerated electrons and holes were the primary active species involved in RhB and pendimethalin photodegradation, respectively. Ba 1.9 Ho 0.1 Sr 1.5 Ni 0.5 Fe 12 O 22 @MXene showed increased photocatalytic behavior because it has increased surface area which decreases rate of recombination of electron and hole pair, hence photocatalytic activity increases. It is observed that Ba 1.9 Ho 0.1 Sr 1.5 Ni 0.5 Fe 12 O 22 @MXene has potential application in photocatalytic degradation of harmful pollutants., Competing Interests: There are no conflicts of interest to declare for our manuscript being submitted to your journal., (This journal is © The Royal Society of Chemistry.)

Metallic nanowires (NWs) and their different compounds display incredible prospects for their use in various applications including media storage, sensor and solar cell devices along with the biological drug delivery systems. In this research work, the metallic NWs like nickel nanowires (Ni-NWs) are synthesized successfully by employing electrodeposition process. Anodic aluminum oxide (AAO) templates are employed as a platform with copper metal coating which acts as an active cathode. The synthesized Ni-NWs are examined through various characterization techniques including X-ray diffraction (XRD), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM) to study the crystal structure, surface morphology and magnetic properties, respectively. The XRD analysis shows the development of various diffraction planes like Ni (111), Ni (200), Ni (220) which confirms the formation of polycrystalline nickel NWs. The SEM analysis reveals that the range of diameter and length of nickel NWs are found to be ∼160 to 200 and ∼4 to 11 micron respectively showing high aspect ratio (ranged from ∼200 to 300). The ferromagnetic behavior of Ni-NWs is confirmed by the hysteresis loop carried out for parallel and perpendicular configurations having H c = 100 and 206 Oe, respectively. The obtained results suggest that the synthesized Ni- NWs may be used for high-density media storage devices., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors.)

Two-dimensional (2D) material-based heterostructures gain increasing interest due to their extraordinary properties and excellent potential for the optoelectronic devices. This study deals with modulation of electronic and optical properties of the ZrS 2 /PtS 2 van der Waals heterostructure under vertical strain and an external electric field based on first principles calculation. Different stacking of ZrS 2 and PtS 2 layers are considered for the heterostructure formation and the most stable structure with lowest binding energy is selected for further calculations. The stable ZrS 2 /PtS 2 heterostructure shows an indirect band gap of 0.74 eV, which is smaller than that of both ZrS 2 and PtS 2 monolayers. With the applied external electric field, the band gap value of the ZrS 2 /PtS 2 heterostructure increases with the negative electric field and decreases with the positive electric field. It is observed that the indirect-to-direct band gap transition occurs when the highest negative value of the electric field is applied. In the case of vertical strain applied to the heterostructure, with an increase in compressive strain, the band gap decreases and vice versa for tensile strain. Optical absorption spectra show significant absorption in the visible light region to the ultraviolet light region. This study shows that the electronic and optical properties of ZrS 2 /PtS 2 heterostructures can be modulated by using vertical strains and an external electric field., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)