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Due to the development of the petroleum industry, more severe mining conditions put forward higher corrosion resistance requirements for materials. In this paper, the corrosion resistance and corrosion behavior of four TC4-xNi-yNb (x, y = 0, 0.5) alloys were investigated in a 1 mol/L HCl solution through microscopic characterization, electrochemical tests and corrosion weight loss testing. The results demonstrated that the addition of Ni and Nb elements could improve the corrosion resistance of TC4 alloy to varying degrees. The addition of niobium formed niobium oxide in the passive film, while the addition of nickel thickened the passive film without formation of nickel oxides. The improvement of corrosion resistance of TC4 by nickel is more significant. Finally, a new highly corrosion resistant alloy TC4-0.5Ni-0.5Nb is preferred. [ABSTRACT FROM AUTHOR]

Sintering additives have been widely employed to achieve good sinterability of barium-based proton-conducting perovskites (based on BaZrO 3 , BaCeO 3 , BaTiO 3 , BaHfO 3 , BaThO 3 , and BaSnO 3). This is of particular importance for the fabrication of multilayered ceramic cells, in which the thin-film electrolyte layer can be primarily densified at relatively low sintering temperatures (1350–1500 °C). The introduction of sintering additives facilitates the fabrication of gas-tight ceramics; however, the precise nature of their localization due to submicron states as well as their effects on the functional properties remain uncertain and even questionable. In this study, we present a comprehensive characterization of ceramic materials based on Y-doped BaSnO 3 prepared with the addition of 1 wt% of three sintering additives (copper, cobalt, and nickel oxides). Although these introduced oxides belong to a group of compounds with similar physicochemical properties, each additive exerts a distinct influence on the microstructural and electrochemical properties of the ceramics owing to their own chemical localization features. The present work provides a detailed discussion of these features, employing a precise microstructural analysis of both the as-prepared ceramics and their reduced derivatives to facilitate exsolution processes. The obtained findings can be extrapolated to other proton-conducting perovskites, thereby providing a rationale for revisiting the application of high-quality ceramics in protonic ceramic electrochemical cells. [Display omitted] • MO x sintering additives (M = Cu, Co, Ni) were used to prepare dense BaSnO 3 ceramics. • The effect of MO x on the microstructural properties was comprehensively evaluated. • Both oxidized and reduced Y-doped BaSnO 3 ceramic materials were analyzed. • The localization nature of MO x was revealed. [ABSTRACT FROM AUTHOR]

Alumina supported copper oxide (CuO/Al2O3) and Nickel Oxide (NiO) loaded polymer composite matrices supported n‐hexadecane (HD) based composite phase change materials (PCMs) are prepared and characterized. The polymer composites assigned as supporting matrices for shape‐stabilization of PCM are synthesized by emulsion‐templating approach, and the composite PCMs are prepared by impregnation of HD into polymer composite matrices. The effect of CuO/Al2O3 and NiO particles of different sizes used as heat transfer promoters in the supporting matrices, on the morphological properties, thermal stabilities, and latent heat storage characteristics (LHS) of the composite PCMs are evaluated using different characterization methods. The melting temperature of the obtained composite PCMs is found to be ≈18 °C and the latent heat of melting values varied in the range of 95.0−114.5 J g−1. The heat transfer properties of the composite PCMs are investigated by performing a T‐History test for obtaining heat storage and release curves. The composite PCMs with NiO loaded supporting matrices are exhibited higher thermal stability and heat storage capacity in addition to enhanced thermal conduction properties than the CuO/Al2O3 included composite PCMs. According to the results, it is revealed that shape‐stabilized, thermally enhanced composite PCMs are remarkable energy storage materials with the potential for use in low‐temperature thermal energy storage systems. [ABSTRACT FROM AUTHOR]

Nanosized materials are increasingly being recognized as inherent components in the development of energy storage devices and other state-of-the-art dielectric applications. In this work, nickel oxide (NiO), cobalt oxide (Co3O4) and NiO–Co3O4 nanocomposites in different compositions (10%, 20%, 30% and 40%) were successfully synthesized through hydrothermal method, optimizing concentrations of the precursors, and X-ray diffraction confirmed single-phase polycrystalline NiO and Co3O4. SEM images showed that distinct morphologies for each material and FTIR spectra reveal Ni–O and Co–O. UV–visible analysis shows a plasmon peak at 307 nm for NiO and excition absorption at 282 nm for Co3O4. NiO–Co3O4 nanocomposites displayed band gaps ranging from 2.37 eV to 2.67 eV. Dielectric properties showed a decrease in εʹ with frequency, attributed to Maxwell–Wagner and hopping models. AC conductivity increased with frequency due to Co3O4 content and oxygen vacancies. The study suggests potential applications in supercapacitors, spintronics, high-frequency devices and ultra-high dielectric materials. [ABSTRACT FROM AUTHOR]

Magnetic Cobalt Oxide (CoO/Co2O3/Co3O4) and Nickel Oxide (NiO) Nanoparticles have been widely reported as heterogeneous catalysts for the preparation of derivatives of heterocycles. These are abundant, eco-friendly, relatively nontoxic and inexpensive catalysts. This review consists of the previous 10-year publications on the catalytic applications of Cobalt Oxide and Nickel Oxide Nanoparticles for the synthesis of heterocycles and their derivatives. Among the various metal oxide nanomaterials reported in the literature as catalyst materials for the synthesis of varied heterocycles and their derivatives, we have kept our focus on the key materials viz. Cobalt Oxide and Nickel Oxide Nanoparticles. In the conclusion part, we have also commented on the better options for the catalyst selection among the reports covered in this paper. This paper will definitely be useful for new researchers in the metal oxide nanomaterials-based catalytic applications for synthetic heterocyclic compounds. [ABSTRACT FROM AUTHOR]

The composites based on hollow glass microspheres (HGMs) decorated with nanoparticles of nickel and iron oxides were prepared from the nitrate solutions with ultrasound treatment. Further exposition of these composites in a hydrogen-helium flow leads to the formation of nanosized bimetallic particles of Ni(80)Fe(20) (number in the brackets is estimated as wt%) that are effective in the catalytic reaction of CO2 hydrogenation to methane. Investigation of CO2 conversion was carried out under gas chromatographic control, and methane yield was evaluated for composites with 20 and 60 wt% of grafted bimetallic mass. The TPD MS method was used to study the processes of desorption of particles involved in the mechanism of methane formation. Textural and structural characteristics of as-prepared and post-reacted composites were examined using low-temperature nitrogen adsorption and X-ray diffraction methods. [ABSTRACT FROM AUTHOR]

The composites based on hollow glass microspheres (HGMs) decorated with nanoparticles of nickel and iron oxides were prepared from the nitrate solutions with ultrasound treatment. Further exposition of these composites in a hydrogen-helium flow leads to the formation of nanosized bimetallic particles of Ni(80)Fe(20) (number in the brackets is estimated as wt%) that are effective in the catalytic reaction of CO2 hydrogenation to methane. Investigation of CO2 conversion was carried out under gas chromatographic control, and methane yield was evaluated for composites with 20 and 60 wt% of grafted bimetallic mass. The TPD MS method was used to study the processes of desorption of particles involved in the mechanism of methane formation. Textural and structural characteristics of as-prepared and post-reacted composites were examined using low-temperature nitrogen adsorption and X-ray diffraction methods. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO), nickel hydroxide (Ni(OH)2), and nickel sulfide (NiS) nanoparticles have been fabricated using a simple co-precipitation method. The effect of different structures and morphologies of the prepared nanoparticles on a supercapacitor have been investigated. The prepared nanoparticles were characterized by UV, XRD, FESEM, and EDAX. The XRD demonstrated face centered cubic (FCC), hexagonal, and rhombohedral molecular structures of the nanoparticles. The FESEM analysis found a non-uniform aggregated spherical morphology of NiO, a rock-like morphology of Ni(OH)2, and an irregular spherical morphology of NiS. In KOH electrolyte, NiO stainless-steel electrodes showed a better performance, exhibiting a high specific capacitance of 438 F/g with a good cycling stability of 87% after 1000 cycles. NiO has the lowest conducting resistance among the three nanoparticles, was effectively optimized as a superior electrode, and yielded the greatest pseudo-capacitance by carbon-free electrode fabrication. This study suggests simple ways to enhance a supercapacitor's electrochemical characteristics. [ABSTRACT FROM AUTHOR]

Molybdenum trioxide (α‐MoO3) is a promising and inexpensive alternative to platinum group metals (PGMs), for electrocatalytic hydrogen evolution reaction (HER). However, to make it a viable candidate for electrocatalytic systems, we must address the hurdles associated with its inferior electrical conductivity and lack of active sites. Unlike Mo‐based compounds such as MoS₂ and MoSe₂, which possess catalytically active edges, α‐MoO₃ lacks inherent active sites for HER. Previous studies have employed various strategies to activate MoO₃ for HER, yet its activation in near‐neutral conditions remain largely unexplored. In this study, a previously known α‐MoO3 intercalating {Ni(H2O)6}2+, [MoVI2O6(CH3COO){NiII(H2O)6}0.5] ⋅ H2O (Ni(H2O)6@MoO3) is prepared via a simple and scalable room‐temperature aqueous synthesis. In the subsequent aerial thermal annealing process at 300, 400 and 500 °C, Ni(H2O)6@MoO3 acts as a self‐sacrificial template, yielding mixed metal oxide composites of nickel and molybdenum (named as MoO3‐300, MoO3‐400 and MoO3‐500). The HR‐TEM and XPS analyses confirm the formation of the Ni2O3 phase alongside the orthorhombic α‐MoO3. The annealing temperature plays a key role in the crystallinity, phase, morphology, and electrocatalytic performance of the resulting composites. The composite formed at 400 °C (MoO3‐400) shows the best electrocatalytic performance among them, showcasing a fivefold enhancement in the HER current density as compared to that shown by commercially available α‐MoO3 in mildly acidic acetate buffer. The enhanced performance towards HER by MoO3‐400 could be attributed to the nanostructured morphology attained via thermal treatment, which provides greater access to the surface sites and the synergistic interaction between the nickel oxide phases and MoO₃ structure, enabling an intermediate pH HER activity rarely reported for molybdenum oxide materials. [ABSTRACT FROM AUTHOR]

The objective of this research is to explore the photocatalytic properties of poly(vinyl chloride) (PVC) films, both pure and doped with varying concentrations of nanoscale nickel oxide (NiO), fabricated using the spin-coating technique. The concentrations of NiO used were 8%, 10%, and 20%. Various analytical methods were employed to characterize the samples. The presence of NiO nanocrystals within the PVC films was confirmed through X-ray diffraction, Raman spectroscopy, and infrared spectroscopy. X-ray diffraction analysis revealed an average particle size of 12 nm for the NiO. Raman spectroscopy of the nanocomposites showed additional low-intensity lines characteristic of the NaCl phase of NiO cubic (NaCl type) within the PVC host matrix, indicating excellent crystalline quality with low defect density. FTIR infrared spectroscopy confirmed the presence of peaks corresponding to the Ni–O bond vibration, with increased visibility of the absorption band of NiO as doping percentages increased. Optical analysis revealed distinct differences between the spectra of pure and doped matrices. Doping led to increased absorption, characterized by the emergence of absorption bands and a redshifted absorption edge compared to the bulk semiconductor. The optical band gap of the nanocomposites decreased with increasing NiO concentration, ranging from 3.71 to 3.90 eV. PVC/NiO nanocomposites exhibited broad luminescence across the visible to near-UV range, suggesting potential applications in optical systems operating within this spectral range. Photocatalytic activity assessments demonstrated that the inclusion of NiO nanoparticles enhanced the efficiency of the composites under UV light. The (PVC/20% NiO) sample exhibited a 65% efficiency in removing MR within 100 min, comparable to other samples with lower efficiency. The photodecomposition reaction of MR followed first-order kinetics, characterized by a rate constant (k) of 0.0098 min−1. [ABSTRACT FROM AUTHOR]

The conversion of ambient mechanical vibrations into electricity using piezoelectric nanogenerators (PENGs) has garnered significant attention from researchers over the past few years, in light of its potential in wearable applications. The high flexibility and significant ferroelectricity of poly(vinylidene fluoride) (PVDF) make them the most promising candidates for PENG applications among polymer piezoelectric materials. In the present work, NiO nanoparticles were incorporated in different ratios into a PVDF matrix, and their potential for use in piezoelectric nanogenerators was investigated. The PVDF/NiO (5 wt.%) nanocomposite PENG exhibited the highest electrical output, with a 2.8-fold increase in open-circuit voltage and short-circuit current observed as compared to a bare PVDF-based PENG. However, a further increase in the compositional ratio of NiO led to a decrease in PENG output. The improved piezoelectricity in the PVDF/NiO (5 wt.%) nanocomposite is attributed to the enhanced polar phases and improved ferroelectricity of PVDF. Further confirmation of the improved piezoresponse was explored by measurement of the piezoelectric coefficient (d33) and dielectric study of the nanocomposites. The PENG electrical output was further simulated using the finite elemental method in COMSOL Multiphysics 5.5. The simulated results matched well with the experimental output, which confirmed the improved electrical performance of the PVDF/NiO nanocomposite-based PENGs. The enhanced performance of the nanocomposite PVDF film is attributed to the higher β phase in the PVDF. The efficiency of the PENG devices in motion-sensing applications was also explored. Different output voltage signals corresponding to different movements of the nanocomposite-based PENGs make the device compatible with sensor applications. [ABSTRACT FROM AUTHOR]

This work focuses on the synthesis and characterization of nanoscale nickel oxide (NiO) nanoparticles doped with manganese (Mn) utilizing the cost-effective co-precipitation technique. For extensive characterization, a range of analytical methods are used, such as photoluminescence (PL) spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, ultraviolet–visible (UV) spectroscopy, and Brunauer–Emmett–Teller (BET) surface area analysis. The findings demonstrate that the addition of Mn causes the synthesized nanoparticles' crystalline size to decrease, which narrows the band gap to 3.13 eV. Furthermore, compared to pure NiO (44.11 m2/g), the surface area of Mn-doped NiO increases to 178.87 m2/g. Also as compared to pure NiO the electron-hole recombination rate of % Mn-doped NiO has decreased and an increase in the defect is observed. The study of Mn-doped NiO nanoparticles' photocatalytic activity against Rhodamine B (Rh. B) demonstrates their improved efficiency under solar light irradiation, as evidenced by their degradation up to 97.57 %, which is higher than that of pure NiO (90.94 %) in 70 min. Numerous aspects are investigated, including pH, catalyst dosage, original dye concentration, and scavenger studies. Studies on regeneration show that 5 % Mn-doped NiO nanoparticles may be recycled effectively and steadily for up to five cycles. These results demonstrate how effective photocatalysts for environmental remediation applications may be made from Mn-doped NiO nanoparticles. [ABSTRACT FROM AUTHOR]

Green synthesis of nanomaterials is advancing due to their ease of synthesis, cheapness, nontoxicity, and renewability. An environmentally friendly biogenic method has been developed for the green synthesis of nickel oxide nanoparticles (NiO NPs) using phytochemical-rich bioextract. They are rich in bioextract phenolics, flavonoids, and berberine. These phytochemicals successfully reduce and stabilize NiNO3 into NiO NPs. In this study, NiO NPs were synthesized by the green synthesis method from Lupinus Albus. Characterization of NiO NPs was carried out by TEM, XRD, SEM, UV, XRF, BET, and EDX analyses. According to XRD analysis, TEM results also support this, where the NiO NPs particle size diameter is 5 nm. It was determined by the Tauc equation that the band energy gap of NiO NPs is 1.69 eV. It was determined that the BET surface area of NiO NPs was 49.6 m2/g. NiO nanoparticles synthesized from Lupinus Albus extract by the green synthesis method were used as catalysts in the photocatalytic reduction of methylene blue with NaBH4. In the photocatalytic reduction of methylene blue with NaBH4, it was determined that there was no color change in 48 h without a catalyst, and in the presence of NiO nanoparticle catalyst, methylene blue was reduced by 97% in 8 min. The kinetics of the photocatalytic reduction of methylene blue with NaBH4 is a pseudo-first-order kinetic model and the kinetic rate constant is determined as 0.66 min−1, indicating that the catalytic effect of NiO NPs is very high at this value. NiO NPs were used five times in the photocatalytic reduction of methylene blue with NaBH4 and it was determined that the reduction of methylene blue was over 90% in each use. NOVELTY STATEMENT: NiO nanoparticles were synthesized from Lupinus Albus extract by green synthesis, which is an easily applied, cost-effective, and environmentally friendly method. The synthesized NiO nanoparticles were characterized using various characterization techniques. NiO nanoparticles have a high catalytic effect in the photocatalytic reduction of methylene blue with NaBH4. Photocatalytic reduction of methylene blue with uncatalyzed NaBH4 could not be achieved, and 97% reduction of methylene blue was completed in 8 min in the presence of NiO nanoparticle catalyst. [ABSTRACT FROM AUTHOR]

This work explores the thickness effect of RF magnetron-sputtered nickel oxide (NiO) thin films for evaluating their H2S gas-sensing characteristics. NiO thin films were prepared on alumina substrates by varying the deposition time, and the resulting film thicknesses were 25 nm, 52 nm, and 76 nm. X-ray diffraction results demonstrate the polycrystalline nature and cubic structure of NiO thin films. Photoluminescence spectroscopy measurements revealed increased defect content (Ni interstitials and O vacancies) in the 52-nm-thick NiO thin film. Furthermore, X-ray photoelectron spectroscopy results confirmed the thickness effect on NiO thin film stoichiometry. Conductivity measurements at working temperatures ranging from 200 to 450 °C were also used to investigate the gas-sensing tests. The NiO thin film with a thickness of 52 nm proved to be an excellent H2S gas sensor, with a remarkable sensor response of 260% and a response/recovery time of ~ 52 s/23 s for 50 ppm H2S at a relatively low operating temperature of 275 °C. Additionally, the film displays a low H2S detection limit of ~ 0.2 ppm. This study investigates the relationship between the thickness, structural, optical, and electrical properties of NiO thin film-based H2S gas sensors and their gas-sensing capabilities. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiOx) serves as one of the most promising hole transport materials for perovskite light‐emitting diodes (PeLEDs). However, only moderate PeLED performances have been reported on the pristine NiOx layer due to insufficient hole injection, interfacial exciton quenching, and poor perovskite quality. Herein, a multifunctional molecule of 3‐mercapto‐1‐propanesulfonate (MPS) is demonstrated to successfully tailor the NiOx–perovskite heterogenous interface by addressing the above issues. In detail, the large binding energy between mercapto sulfur and nickel induces preferential self‐assembly of the mercapto group on the NiOx surface, which simultaneously enlarges the NiOx work function by the formation of interfacial dipole and suppresses the trap‐assisted exciton quenching by the passivation of the oxygen vacancies. Meanwhile, the self‐assembled MPS on NiOx also favors high‐quality perovskite films with good morphology, high crystallinity, and reduced defects for efficient carrier radiative recombination. As a result, blue PeLEDs show a remarkable efficiency of 10.4%, representing one of the highest efficiencies for NiOx‐based blue PeLEDs, as well as a very low turn‐on voltage of 2.8 V. Consequently, this work contributes to an efficient approach to tailor the NiOx–perovskite interface for highly efficient blue PeLEDs. [ABSTRACT FROM AUTHOR]

Inorganic photocatalytic materials exhibiting a highly efficient response to ultraviolet-visible light spectrum have become a subject of widespread global interest. Nanocomposite metal oxides, particularly Nickel Oxide (NiO) and Zinc Oxide (ZnO), have gained attention for their diverse applications in gas sensing and photocatalytic processes. In this work, ZnO-NiO (ZnO0.6NiO0.4 and ZnO0.4NiO0.6) binary nanocomposites were synthesized by hydrothermal technique. The binary nanocomposites were analyzed by UV-Visible spectrophotometer, X-ray diffraction (XRD), photoluminescence (PL), Fourier transform infrared spectrophotometer (FTIR), energy dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The XRD pattern revealed that the nanocomposites, the peaks of both ZnO and NiO are present indicating the presence of both crystal structures hexagonal wurtzite and cubic. The miller indices, crystallite size, microstrain and dislocation density were determined from the XRD plot. FESEM and TEM analyses showed the spherical morphology of the synthesized composites with an approximate size of 10nm. The detailed analysis of ZnO–NiO binary nanocomposite sensor characteristics in terms of sensitivity, selectivity, response and recovery time were carried out and the nanocomposites were found to be highly sensitive to CO2 100 ppm at 350∘C and Cl2 at 200∘C. The photocatalytic degradation outcome showed 52% degradation of methylene blue at 10 ppm and 90w/m2. These results suggest the potential utility of these binary nanocomposites in photocatalytic applications for the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

We demonstrated a nonenzymatic electrochemical sensor based upon vanadium-doped nickel oxide composite with graphitic carbon nitride. The g-C 3 N 4 was prepared by annealing Urea at 550 °C for 3 h in a muffle furnace. The nanocomposite was synthesized using a microwave-assisted method, followed by thermal annealing at different temperatures. The successful formation of V–NiO/g-C 3 N 4 was confirmed by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy. SEM images show the layered sheets with porous structure, which depends on annealing temperature; as we increase the temperature, the porosity increases. Afterwards, the electrochemical sensing properties were verified by CV, LSV, DPV, and amperometric studies in 0.2 M KOH in the presence of Ascorbic acid and Dopamine. The experimental results show that our prepared sample has excellent electrochemical biosensing abilities towards AA and DA with LOD 1.16 μM and 0.16 μM, respectively. It also offers good selectivity, exceptional reproducibility, and long-term stability owing to the combined effect of NiO and g-C 3 N 4. Finally, the electrochemical sensing of H 2 O 2 was detected in the same environment by conducting CV and amperometric studies. Our modified electrode has proven its noble ability to sense H 2 O 2 with excellent repeatability, stability and low LOD 0.2 μM with a wide linear working range (0.5 mM–4 mM). It has the potential to be used for multi-molecule selection biosensing with excellent selectivity and sensitivity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel S-scheme NiO/PbBiO 2 Br composites are synthesized through a hybrid approach combining hydrothermal and photodeposition methods. • NiO/PbBiO 2 Br composites demonstrate dual energy harvesting capabilities from solar and vibration sources. • A synergistic effect between piezocatalysis and photocatalysis is observed in NiO/PbBiO 2 Br. • NiO/PbBiO 2 Br exhibits significantly increased photoactivity in RhB degradation. • Enhanced charge separation efficiency is achieved in NiO/PbBiO 2 Br via an S-scheme mechanism. The fabrication of an S-scheme heterojunction demonstrates as an efficient strategy for achieving efficient charge separation and enhancing catalytic activity of piezocatalysts. In this study, a new S-scheme heterojunction was fabricated on the PbBiO 2 Br surface through the photo-deposition of NiO nanoparticles. It was then employed in the piezoelectric catalytic degradation of Rhodamine B (RhB). The results demonstrate that the NiO/PbBiO 2 Br composite exhibits efficient performance in piezocatalytic RhB degradation. The optimal sample is the NiO/PbBiO 2 Br synthesized after 2 h of irradiation, achieving a RhB degradation rate of 3.11 h−1, which is 12.4 times higher than that of pure PbBiO 2 Br. Simultaneous exposure to visible light and ultrasound further increases in the RhB degradation rate, reaching 4.60 h−1, highlighting the synergistic effect of light and piezoelectricity in the NiO/PbBiO 2 Br composite. A comprehensive exploration of the charge migration mechanism at the NiO/PbBiO 2 Br heterojunction was undertaken through electrochemical analyses, theoretical calculations, and in-situ X-ray photoelectron spectroscopy analysis. The outcomes reveal that p-type semiconductor NiO and n -type semiconductor PbBiO 2 Br possess matching band structures, establishing an S-scheme heterojunction structure at their interface. Under the combined effects of band bending, interface electric fields, and Coulomb attraction, electrons and holes migrate and accumulate on the conduction band of PbBiO 2 Br and valence band of NiO, respectively, thereby achieving effective spatial separation of charge carriers. The catalyst's synergistic photo-piezoelectric catalysis effect can be ascribed to its role in promoting the generation and separation of charge carriers under both light irradiation and the piezoelectric field. The results of this investigation offer valuable insights into the development and production of catalytic materials that exhibit outstanding performance through the synergy of piezocatalysis and photocatalysis. [ABSTRACT FROM AUTHOR]

The green synthesis of nanoparticles using lichen extracts offers a safer and more environmentally friendly alternative to traditional methods. Known for their medicinal properties, lichens can effectively reduce and stabilise metallic salts, providing an eco-friendly approach to producing nanomaterials with potential antimicrobial applications. In this study, the lichen Rhizoplaca chrysoleuca was utilised in the green synthesis of nanoparticles, successfully creating lichen-derived silver-zinc oxide (Ag–ZnO), silver-strontium oxide (Ag–SrO), and silver-nickel oxide (Ag–NiO) nanoparticles. Ultraviolet–visible absorption spectroscopy revealed that the characteristic light absorption of the NCs occurred within the range of 300–400 nm for each synthesis, and dynamic light scattering measurements indicated that the hydrodynamic diameters of the nanoparticles were below 100 nm. Energy-dispersive X-ray spectroscopy confirmed the presence of the constituent elements. Imaging with field-emission scanning electron microscopy and scanning transmission electron microscopy showed that the nanoparticles had spherical shapes with dimensions measuring below 50 nm. X-ray diffraction analysis of the synthesised nanocomposite materials revealed the presence of Ag–ZnO (22 nm), Ag–SrO (48 nm), and Ag–NiO (21 nm) nanoparticles. Fourier-transform infrared spectroscopy identified functional groups in the nanoparticles, confirming their compositions, while thermogravimetric analysis determined the thermal decomposition temperatures of the NCs. The antibacterial efficacy of these materials was assessed, with Ag–ZnO (inhibition zone 11.0 mm) and Ag–NiO (inhibition zone 10.0 mm) showing significant effectiveness against both Gram-negative and Gram-positive bacteria. In contrast, Ag–SrO (inhibition zone 6.5 mm) exhibited comparatively lower antibacterial activity. Additionally, the study highlighted the antifungal properties of Ag–NiO (inhibition zone 19.0 mm) and Ag–ZnO (inhibition zone 8.5 mm) nanomaterials. This research advances the understanding of lichen-based nanotechnology and its potential for developing sustainable antimicrobial solutions. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, an electrochemical technique was used to deposit nickel oxide on stainless steel (SS) substrates with varying amounts of the precursor nickel nitrate (N1-0.5M, N2-1M and N3-1.5M), and nickel hydroxides Ni(OH)2 are electrodeposited on the SS substrate. After that, they were subjected to heat treatment to become a homogeneous nickel oxide nanoparticle layer. The deposited films were performed for the structural and morphological analysis by X-ray diffraction, scanning electron microscopy and FTIR. The maximized N3 film exhibited the highest specific capacitance value of 514 F g−1 at 5 mV s−1 in 1 M KOH aqueous electrolyte with great rate capability, resulting in prolonged cycling. [ABSTRACT FROM AUTHOR]

Thermo‐catalytic co‐pyrolysis of paulownia wood and polypropylene mixture were carried out in a fixed bed horizontal reactor system. The biochar obtained from pyrolysis of paulownia wood was activated by steam at 700°C. Activated biochar supported magnesium oxide, nickel oxide and cobalt oxide catalysts were prepared by incipient miosture impregnation and were used to upgrade the bio‐oil. Catalytic pyrolysis reduced the amount of bio‐oil compared with non‐catalytic pyrolysis (59.5% of bio‐oil). The results indicate that the production of aromatic compounds increased from 40.35% to 65.93, 62.12 and 61.56% using Ni, Co and Mg catalysts, respectively. For all three catalysts, the production of furan compounds decreased. It was found that bio‐char based catalysts are suitable for use in the co‐pyrolysis process to improvement the biofuel production. [ABSTRACT FROM AUTHOR]

Developing p-type oxide thin-film transistors (TFTs) is an essential path for further application in complementary metal oxide semiconductor (CMOS) components. However, the inferior electrical performance of p-type MO TFTs compared to n-type TFTs remains an ongoing challenge. Herein, for the first time, a low temperature, facile material engineering approach by incorporating n-type nanoparticles (NPs) was proposed for preparing p-type transparent NiOx TFTs. The characteristics of thin films blending NPs and the electrical performances of TFTs were investigated. The field effect mobility of TFTs with doping was nearly 20 times higher than pristine TFTs without doping, which was mainly beneficial from the suitable band alignment between NPs and p-type oxide, the increasing Ni3+ oxidation state in NiOx, as well as the improved dielectric/semiconductor interface quality. Electrons from drain electrode injected into metal oxide turn accepted in NPs rather than being trapped in the dielectric/semiconductor interface due to a strong surface electron depletion effect of NPs. NPs with small particle size and appropriate concentration would promote continuous hole transport by electrons transferring and reducing the interface trap state. The facile material engineering strategy is a promising technique for preparing p-type transparent MO-TFTs at low temperature, which showed great potential to be applicable in CMOS circuits on flexible substrates. [ABSTRACT FROM AUTHOR]

Nickel cobalt oxides (NCOs) are promising, non‐precious oxygen evolution reaction (OER) electrocatalysts. However, the stoichiometry‐dependent electrochemical behavior makes it crucial to understand the structure‐OER relationship. In this work, NCO thin film model systems are prepared using atomic layer deposition. In‐depth film characterization shows the phase transition from Ni‐rich rock‐salt films to Co‐rich spinel films. Electrochemical analysis in 1 m KOH reveals a synergistic effect between Co and Ni with optimal performance for the 30 at.% Co film after 500 CV cycles. Electrochemical activation correlates with film composition, specifically increasing activation is observed for more Ni‐rich films as its bulk transitions to the active (oxy)hydroxide phase. In parallel to this transition, the electrochemical surface area (ECSA) increases up to a factor 8. Using an original approach, the changes in ECSA are decoupled from intrinsic OER activity, leading to the conclusion that 70 at.% Co spinel phase NCO films are intrinsically the most active. The studies point to a chemical composition dependent OER mechanism: Co‐rich spinel films show instantly high activities, while the more sustainable Ni‐rich rock‐salt films require extended activation to increase the ECSA and OER performance. The results highlight the added value of working with model systems to disclose structure‐performance mechanisms. [ABSTRACT FROM AUTHOR]

[Display omitted] The silicon- modified nickel oxide catalysts with the same compositions but distinct Ni-Si interactions were obtained via different synthesis routes and utilized for methane combustion under conditions of oscillating temperatures. For catalysts prepared by co-grinding, amorphous SiO 2 was dispersed on the surface of large NiO crystallites. During high-temperature calcination or reactions, the crystallization of SiO 2 , coupled with the sintering or decomposition of NiO crystallites, led to the inferior catalytic activity and stability. Interactions between Ni and Si species were enhanced in catalysts synthesized by precipitation. The Si species was incorporated into the NiO lattice to inhibit the growth of NiO crystallites and to generate nickel silicate species under thermal treatments. The small NiO crystallites provided more Ni3+ and active oxygen species for methane activation and oxidation, while the bulk nickel silicate species played a pivotal role in improving thermal stability, conjointly provoking excellent catalytic performance in cyclic heating–cooling tests between 180 and 800 °C. This study offers new insights into the design of metal oxide composites for catalytic applications. [ABSTRACT FROM AUTHOR]

As interest in pin perovskite solar cells (PeSCs) capable of low temperature solution process increases, research on the low temperature solution processable hole transport layer (HTL) is emerging as an important issue. Although a solution processed nickel oxide (NiO) has been spotlighted as an optimal HTL, high temperature post treatment over 250 ℃ is required for suff cient device performance. In this study, NiO film fabricated from presynthesized NiO nanoparticle dispersion is investigated as HTLs and their interface is modified with [4-(3,6 dimethyl-9H carbazol 9 yl)butyl]phosphonic acid (Me 4PACz) to demonstrate highly efficient PeSCs processed at ~100 ℃. The combination of the low temperature processed NiO with optimal thickness (~10 nm) and Me 4PACz exhibits higher efficiency of 17.4% comparing to bare NiO based device showing 12.4%. Me 4PACz modification on NiO results in an improved energy level alignment with perovskite and more hydrophobic NiO/Me 4PACz induces excellent perovskite layer with larger grain and high crystallinity. Furthermore, the NiO/Me-4PACz-based PeSC maintains 83% of their initial efficiency after 140 days in air. This result shows that our low temperature solution processed NiO/Me 4PACz can be a promising candidate as HTLs even in terms of stability. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to develop flexible conductive biopolymer blend nanocomposites using polyindole (PIN) and carboxymethyl chitosan (CMC) with various nickel oxide (NiO) nanoparticles by in-situ polymerization techniques. Different techniques were used to study the effect of NiO content on the structural, optical, morphological, thermal, mechanical and electrical characteristics of PIN/CMC blend nanocomposites. Fourier-transform infrared spectroscopy (FT-IR) demonstrated that the introduction of NiO nanoparticles resulted in chemical bonding with the PIN/CMC blend, as evidenced by the formation of a new peak at a wavenumber of 603 cm− 1. The lowest optical bandgap energy was found in 10 wt% composites. The increased crystallinity of the blend nanocomposites was evident from X-ray diffraction (XRD) patterns. The scanning electron microscopy (SEM) and the energy dispersive X-ray (EDX) analysis confirmed the presence of NiO nanoparticles in the PIN/CMC blend. High-resolution transmission electron microscopy (HR-TEM) images revealed that the NiO particles were homogeneously dispersed in the blend matrix at a manometer scale. The thermogravimetric analysis (TGA) demonstrated that the reinforcement of NiO significantly improved the thermal stability of PIN/CMC blend from 202 to 223 °C. Electrical conductivity improved significantly as the temperature and nanoparticle dose increased. The tensile strength of the 7 wt% NiO-loaded PIN/CMC blend nanocomposite was 102% higher than that of the pure PIN/CMC blend. This PIN/CMC/NiO nanocomposite has high tensile strength, thermal stability, dielectric constant and electrical properties, making it suitable for a wide range of applications, including energy storage and flexible nano-electronic devices. [ABSTRACT FROM AUTHOR]

In both the manufacturing and chemical industries, benzoquinone is a crucial chemical product. A perfect and economical method for making benzoquinone is the electrochemical oxidation of phenol, thanks to the traditional thermal catalytic oxidation of phenol process requires high cost, serious pollution and harsh reaction conditions. Here, a unique heterostructure electrocatalyst on nickel foam (NF) consisting of nickel sulfide and nickel oxide (Ni9S8‐Ni15O16/NF) was produced, and this catalyst exhibited a low overpotential (1.35 V vs. RHE) and prominent selectivity (99 %) for electrochemical phenol oxidation reaction (EOP). Ni9S8‐Ni15O16/NF is beneficial for lowering the reaction energy barrier and boosting reactivity in the EOP process according to density functional theory (DFT) calculations. Additionally, an alkali/acid hybrid flow cell was successfully established by connecting Ni9S8‐Ni15O16/NF and commercial RuIr/Ti in series to catalyze phenol oxidation in an alkaline medium and hydrogen evolution in an acid medium, respectively. A cell voltage of only 0.60 V was applied to produce a current density of 10 mA cm−2. Meanwhile, the system continued to operate at 0.90 V for 12 days, showing remarkable long‐term stability. The unique configuration of the acid‐base hybrid flow cell electrolyzer provides valuable guidance for the efficient and environmentally friendly electrooxidation of phenol to benzoquinone. [ABSTRACT FROM AUTHOR]

In the current paper, a NiO nanoparticles-loaded mesoporous carbon (CMK-3) catalyst, denoted as NiO/CMK-3, has been successfully synthesized using a facile strategy. The as-prepared material has been characterized through XRD, Raman spectroscopy, low-temperature N2 physisorption measurements, FTIR, FE-SEM, TEM, and XPS. The as-fabricated NiO/CMK-3 catalyst manifested a superior activity in the NaBH4-assisted reduction of methylene blue (MB) dye to its colorless leuco form. Remarkably, over 99% of 25 mg L−1 MB was reduced by 7.5 mM/L NaBH4 using 0.1 g L−1 NiO/CMK-3 within 3 min at room temperature. Furthermore, the kinetics study confirmed the appropriateness of the pseudo-first-order kinetic model for elucidating the kinetics of MB reduction by the catalyst. Importantly, the NiO/CMK-3 catalyst maintained almost constant catalytic activity even after 5 times of reuse in MB reduction, demonstrating its superior stability and reusable ability. So, NiO/CMK-5 appears as a promising heterogeneous catalyst for the effective remediation of dye-containing wastewater. [ABSTRACT FROM AUTHOR]

The nickel metal nanoparticles and 3D nitrogen-doped carbon matrix are adopted to embellish nickel oxide via a simplified hard template method. This strategy will shine the route to prepare and ameliorate the electrochemical performance of NiO-based electrodes and other-type electrodes for energy storage. [Display omitted] Tailoring the omnidirectional conductivity networks in nickel oxide-based electrodes is important for ensuring their long lifespan, stability, high capacity, and high-rate capability. In this study, nickel metal nanoparticles and a three-dimensional nitrogen-doped carbon matrix were used to embellish the nickel oxide composite NiO–Ni/N–C via simplified hard templating. When a porous nitrogen-doped carbon matrix is present, a rapid pathway would be established for charging and discharging the electrons and lithium ions in a lithium-ion battery, thereby alleviating the volumetric expansion of the NiO nanoparticles during the operation of the battery. Moreover, the Ni0 ions added to serve as active sites to improve the capacity of the NiO-based electrodes and strengthen their conductivities. The multielement-effects of the optimal NiO–Ni/N–C electrode leads it to exhibit a capacity of 1310.8 mAh g-1 at 0.1 A g-1 for 120 loops and a rate capability of 441.5 mAh g-1 at 20.0 A g-1. Kinetic analysis of the prepared electrodes proved their ultrafast ionic and electronic conductivities. This strategy of hard templating reduces the number of routes required for preparing different types of electrodes, including NiO-based electrodes, and improves their electrochemical performance to enable their use in energy storage applications. [ABSTRACT FROM AUTHOR]

Polyaniline‐potassium doped nickel oxide nanocomposites (PANI/KNO) were efficiently synthesized via an in situ chemical oxidation method, meticulously confirmed by comprehensive x‐ray diffraction, Fourier transformation infrared spectroscopy, energy dispersive x‐ray spectroscopy, selected area electron diffraction, and x‐ray photoelectron spectroscopy analyses. The crystallite size and strain exhibited distinct behaviors, while field emission scanning electron microscopy revealed a blend of irregular spherical shapes and nanofibers, further confirmed by high resolution transmission electron microscopy. These composites exhibited significantly enhanced thermal stability, surpassing PANI by 1.39 times, and showcased a band gap exceeding 3 eV, along with multiple photoluminescence peaks at room temperature (RT). Moreover, their RT AC conductivity experienced a remarkable surge by 4.91 times compared to pure polyaniline. Jonscher's Power Law model and the Havriliak–Negami relaxation model are employed to elucidate the electrical properties of composite materials. The composites displayed nonDebye relaxation behavior with increased conductivity, as observed through impedance analysis, electrical modulus evaluation, and dielectric constant assessment. Additionally, evident superparamagnetic properties and multiple magnetic domains further contributed to their effectiveness. The PANI/KNO composite demonstrated photocatalytic efficiency, achieving over 90% degradation of methylene blue dye across four cycles, thus highlighting its superior photostability. Furthermore, investigations into its response to pH variations and scavenger activity underscored its immense potential for highly effective photocatalytic applications. [ABSTRACT FROM AUTHOR]

Nowadays, nickel oxide nanoparticles are in great demands owing to their use in many sectors. These nanoparticles may release into aquatic environment from different industries and cause negative effect on aquatic flora and fauna. Therefore, an effective and efficient method is required to remove these nanoparticles from contaminated water. Hence, the aim of this study was to bioremediate nickel oxide nanoparticles using a macrofungus, Pleurotus fossulatus, and to analyze its impact on fungal physiology. For this purpose, fungal spawns were inoculated in malt dextrose agar media containing different concentrations of nickel oxide nanoparticles (24 mg/l, 48 mg/l, and 100 mg/l) as well as control group (having no nickel oxide nanoparticles) and allowed to grow for a period of 20 days. Fungal mycelia as well as media were collected at different time intervals (5th day, 10th day, 15th day, and 20th day) for evaluation of Ni concentration and different biochemical parameters. Ni removal efficiency of P. fossulatus from media was found to be highest in 48 mg/l (66.98%) followed by 24 mg/l (60.83%) and 100 mg/l (18.03%), respectively. Increased level of metallothionein, lipid peroxidation, activity of different antioxidant enzymes (superoxide dismutase, catalase, glutathione s transferase, glutathione reductase), activity of ligninolytic enzymes (laccase, lignin peroxidase, manganese peroxidase), and shift in FTIR spectra were also reported in mycelia cultured in malt dextrose agar media containing nickel oxide nanoparticles. This study suggests that P. fossulatus has great efficiency to remediate nanoparticles from contaminated water and it can be utilized as potential agent in wastewater treatment plants by different industries. [ABSTRACT FROM AUTHOR]

Metal oxides are recognized as exemplary materials for photocatalytic dye degradation attributed to their unique characteristics such as tunable electronic structure, prolonged stability, and cost-effectiveness. However, the wide band gap inherent to most of these materials often limits their light absorption to the ultraviolet (UV) region. Consequently, the doping of noble metal nanoparticles into the metal oxide nanostructures has been proposed to significantly improve their light-harvesting ability. This enhancement is primarily ascribed to the localized surface plasmon resonance (LSPR) effect associated with noble metal nanoparticles, which facilitates more effective utilization of light. Thus, in this study, we synthesized silver-doped nickel oxide (Ag:NiO) with varying Ag concentrations (0, 1, 2, 4, 6 wt%) to evaluate their photocatalytic performance. The X-ray diffraction (XRD) spectra revealed that NiO possesses a cubic crystalline structure, and a peak shift to a higher angle was noted for Ag doping, indicative of compressive strain. Further analyses of morphological, vibrational, and absorption properties were conducted through the acquisition of scanning electron microscopy (SEM) images, Raman spectra and UV–Vis absorption spectra, respectively. The photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) dyes was assessed, revealing that NiO with 4.wt.% Ag doping exhibited enhanced photocatalytic activity, achieving 99% degradation of MB and 90% degradation of RhB. Notably, Ag doping significantly enhances the light absorption capabilities and modifies the electronic structure of the NiO, thereby improving its performance in photocatalytic dye degradation. • A novel strategy is proposed to improve the photo-catalytic ability of wide bandgap NiO. • Different concentration of Ag was doped into the NiO lattice. • The LSPR properties of Ag dopants will significantly improve light absorption in the visible region. • Most importantly, 99 % of MB degradation and 90 % of RhB degradation were achieved by Ag dopants. • Catalyst's high degradation efficiency towards MB Dye can be highly useful in wastewater treatment. [ABSTRACT FROM AUTHOR]

Permian alkaline granitoids are widely distributed throughout the Tien Shan Orogen and adjacent region of the southern Central Asian Orogenic Belt. However, their petrogenesis and related tectonic setting remain equivocal. A detailed mineralogical, U-Pb zircon dating, in situ elemental and Sr-Nd-Hf isotopic studies of the uranium-rich Akkulen syenite intrusion in the Northern Tien Shan of Kyrgyzstan were undertaken to better understand its magmatic processes and geodynamic evolution. Four independent oxygen barometers have shown that the oxygen fugacity of the Akkulen syenitic magma evolved from initial low fO2 (NNO +1) during magma ascent and cooling; Apatite geochemical characteristics also indicate that the magma is relatively high F (2.9–5.1 wt.%), with low Cl (0.053–0.13 wt.%) and anhydrous (<4 wt %) contents. According to whole-rock geochemical data, the syenite samples have abnormally high U (38.5–57.1 ppm) and Th (96.2–137 ppm) concentrations, we suggest that high F content and moderate oxygen fugacity are beneficial for uranium enrichment. Zircon grains from a syenite sample yielded a weighted 206Pb/238U age of 283.5 ± 2.6 Ma. The intrusion has an A-type granite affinity with high alkali (Na2O + K2O) contents and Fe/(Fe+Mg) ratios, high LREE/HREE (~5), and low Sr, Ba, and Eu contents. They have negative εNd(t) (−5.2 to −3.6) values with Mesoproterozoic two-stage model ages (T DM2 = 1.35–1.47 Ga), and variable εHf(t) values (−4.6 to +2.4) with Mesoproterozoic two-stage model ages (T DM2 = 1. 2–1.59 Ga), which suggest these rock derivations from the relatively old crustal with minor contribution from juvenile crustal melts. In comparison with regional available dataset, we propose that the alkaline Permian granitoids in Kyrgyz Northern Tien Shan may have been originated from large-scale partial melting of Mesoproterozoic metamorphic basement with minor juvenile crustal material in a post-extensional setting. In contrast, the Early Permian granitoid magmatism in the Tarim Craton may have been caused by the partial melting of Neoproterozoic basement rocks associated with Permian mantle plume activities. [ABSTRACT FROM AUTHOR]

This article presents the growth of uniformly distributed nickel oxide (NiO) nanofibers on a glass substrate by the Successive Ionic Layer Adsorption and Reaction (SILAR) process and explores its photocatalytic features towards an AZO dye. The nanofiber grown by the SILAR process is subjected to annealing at 400°C to decompose the hydroxide group into oxide. X-ray diffraction pattern divulges the Face-Centered Cubic (FCC) structure of NiO, and its average crystallite size (46–61 nm). The fibrous morphology with the width varying from 37.83 to 42.05 nm is confirmed through FESEM micrographs. The existence of nickel and oxide, with atomic percentages in the ratio 40:60 is confirmed by EDX analysis. From the UV–visible spectrum, the band gap energy E g is determined using a Tauc plot and the values are varied between 3.38 eV and and 3.41 eV. Photocatalytic degradation efficiency for the Congo red dye is found to be 93% for reusable NiO nanofibers under the illumination of UV light. The photodegradation pathway of Congo red dye is presented based on gas chromatography-mass spectrometry (GC-MS) analysis. The prospective applications of the current work in wastewater treatment make it significant. [ABSTRACT FROM AUTHOR]

The influence of the annealing medium of thin films of nickel oxide (NiOx) on structural, optical and electrical transport properties is studied in this paper. NiOx films were synthesized by sol-gel method and annealed at a temperature of 300 °C in air, inert nitrogen (N2), oxygen (O2) gases and vacuum. The values of the films thickness were determined from the transverse cleavage of the SEM image. The films thickness depends on the annealing medium. Measurements of the EDX spectra of NiOx films were carried out. Analysis of the quantitative O/Ni ratio showed that the film annealed in an air atmosphere is close to the stoichiometric parameters of NiO. Measurements of the EDX spectra of NiOx films were carried out. According to the Raman spectra, an increase in peak intensities is observed indicating an increase in the density of defects in the film by Ni vacancies depending on the annealing medium. Absorption spectra and Tauc plots of NiOх films were obtained. The optical density of the films depends on the annealing conditions of the films. Data analysis shows that the band gap width depends on the annealing medium and varies from Eg = 3.12 eV to Eg = 3.45 eV. The analysis of the impedance spectra allowed us to estimate the values of the resistances R1 and R2. It is shown that an increase in the resistance of R1 is associated with a decrease in the density of defects in the NiOx film, decrease in the recombination resistance of R2, and an increase in recombination processes at the interface. [ABSTRACT FROM AUTHOR]

Bacterial infections pose a global concern due to high fatality rates, particularly with the rise of drug-resistant bacteria and biofilm formation. There is an urgent need for innovative strategies to combat this issue. A study on chemodynamic therapy (CDT) using nanozymes in conjunction with photothermal therapy (PTT) has displayed potential in addressing drug-resistant bacterial infections. However, the effectiveness of this combined approach is limited by inadequate light absorption. This work suggests the NiOx nanoparticles enriched with oxygen vacancies enhance CDT and PTT to overcome this challenge. The presence of oxygen vacancies in NiOx can reduce the energy gap between its valence band and conduction band, facilitating oxygen adsorption. NiOx has exhibited notable antibacterial properties and complete eradication of biofilms in both laboratory and animal trials. In animal abscess models, NiOx demonstrated antibacterial and anti-inflammatory effects in the initial stages, while also promoting wound healing and tissue regeneration by influencing immune factors and encouraging collagen deposition and neovascularization. With positive biosafety and biocompatibility profiles, the oxygen vacancy-enhanced CDT and PTT therapy proposed in this article hold promise for effective sterilization, deep biofilm removal, and treatment of infections caused by drug-resistant bacteria. This study constructs oxygen vacancies NiOx nanoparticles (NiOx NPs) to improve the efficacy of photothermal therapy and chemodynamic therapy. The presence of oxygen vacancies in NiOx NPs helps bridge the energy gap between its valence band and conduction band, facilitating oxygen adsorption and improving catalytic efficiency. In both in vivo and in vitro antibacterial experiments, NiOx NPs demonstrate effective antibacterial and anti-inflammatory properties. Furthermore, it aids in wound healing and tissue regeneration by modulating immune factors, collagen deposition, and angiogenesis. This approach presents a promising collaborative strategy for utilizing nickel-based defective nanomaterials in combating deep drug-resistant bacterial infections. [Display omitted] [ABSTRACT FROM AUTHOR]

Although revolutionary power conversion efficiency progress has been realized for inverted perovskite solar cells (PSCs), the selection and optimization of the hole‐transporting materials (HTMs) are still crucial for fabricating high‐efficiency, stable, and low‐cost PSCs. Nickel oxide (NiOx) is widely used in the PSCs community for material design and modification. However, various NiOx synthesis processes lead to kinds of NiOx, and it is difficult to determine which NiOx is suitable for application in PSCs. Herein, two kinds of NiOx HTMs are synthesized using sol–gel processed and chemical‐calcination‐processed (CCP) routes for the preparation of PSCs. Based on the physical properties of two kinds of NiOx HTMs as well as the corresponding photovoltaic parameters of PSCs, it is demonstrated that superior NiOx HTMs is obtained by the CCP method with the following properties: high transmittance to ensure sufficient sunlight capture of perovskite, appropriate energy levels to promote hole extraction and transfer, high conductivity to support charge transfer, and a good wetting surface to boost perovskite spreading and film formation. Thus, in this study, the direction for the reasonable selection of HTMs is pointed out to prepare efficient PSCs. [ABSTRACT FROM AUTHOR]

The goal to further increase energy and power density of conventional two-dimensional (2D) structured lithium-ion batteries (LIBs) is driving research towards more complex three-dimensional (3D) batteries with large surface area and accordingly high active material mass loading. So far, many attempts have been implemented to prepare 3D structured LIBs. A highly developed 3D surface allows for a larger amount of active material to be deposited while maintaining a smaller thickness, thus avoiding the challenges associated with a thick electrode. Herein, this paper presents development of in-plane type 3D NiO thin film electrodes produced by radio frequency (RF) magnetron sputtering. The physico- and electro-chemical properties were studied depending on the post-annealing temperature which was in the range of 200-300°C. It was shown that an in-plane NiO thin film anode with GPE can be developed to enable battery operation without the use of a commercial separator. As a gel-polymer electrolyte (GPE) was used poly(ethylene oxide)-poly(vinylidene fluoride) (PEO-PVDF-co-HFP). The in-plane 3D battery with PEO-PVDF-co-HFP GPE exhibited outstanding cycling stability of 60 cycles, delivering a capacity of 510 mAh g-1 . The developed 3D battery, as a result, demonstrated improved cycling stability and electrochemical performance while effectively operating at 0.1C rate. [ABSTRACT FROM AUTHOR]

Even though phytoremediation is considered a green technology for remediating heavy metals, there are some problems with the application of this technology, particularly when it comes to managing the biomass that is used. So, processing biomass needs to be given a lot of attention. This study outlined the utilization of extracts obtained from the hyperaccumulator plant Brassica oleracea var. alboglabra to synthesize nickel oxide nanoparticles. Subsequently, the nanoparticle underwent testing to determine its suitability as an absorbent for heavy metals, specifically lead, as well as its efficacy as an antifungal agent against Fusarium sp. strain. The characterization of nickel oxide nanoparticles involved several measurements, such as scanning electron microscopy analysis, high- and low-resolution transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and hysteresis curve acquisition. The research findings indicate that the extract from hyperaccumulators can be utilized for the synthesis of NiO, which exhibits an absorption capacity exceeding 98% and serves as an efficient antifungal agent against Fusarium sp. pathogens. The approach utilized in this study not only prioritizes "green" and sustainability factors but also takes into account the economic aspects associated with the items being manufactured. The research has important implications in two areas. Firstly, it demonstrates the utilization of natural resources (B. oleracea var. alboglabra) in the production of nickel oxide, which serves as a safer and more eco-friendly substitute for dangerous chemicals. Furthermore, it aids in the advancement of novel techniques for effectively managing biomass hyperaccumulators. [ABSTRACT FROM AUTHOR]

In this current study, hydrothermal method was employed to synthesize distinct nanostructures: pure nickel oxide (NiO), Zn‐doped NiO, and NiO/ZnO composites. X‐ray diffraction (XRD) results confirmed NiO's cubic structure, with sizes of 17.01 nm for pure NiO and 30.87 nm for composites. Scanning electron microscope (SEM) images revealed flowerlike morphologies, energy‐dispersive X‐ray spectroscopy (EDX) authenticated the elemental composition without any impurities. Ultraviolet–visible (UV‐Vis) spectroscopy demonstrated heightened absorption in doped and nanocomposite samples. The bandgap energy calculated using Tauc's plot reduced from 2.95 to 2.55 eV with increase in zinc (Zn) content. In Fourier‐transform infrared (FTIR) characterization, the Ni–O stretching vibration appeared at 666.7 cm−1 in doped samples, while Zn–O stretching was evident at 586.03 cm−1. Photoluminescence analysis unveiled a strong peak at 470 nm (near band edge) and another at 665 nm (indicative of defects), exhibiting intensified signals in doped and nanocomposite samples due to a higher defect density. The dielectric constant showed increased values at low frequencies attributed to real and space charge polarization. Notably, the conductivity of Zn‐doped and nanocomposite samples displayed an upward trend with frequency due to a higher defect density. This study unveils insights into the intricate optical and electrical properties of these novel nanostructures, showcasing their potential in advanced energy storage applications. [ABSTRACT FROM AUTHOR]

Nickel oxide, classified as a metal oxide, has attracted considerable attention across various applications. Nevertheless, its utilization in optoelectronics applications remains relatively uncommon. This study presents a cost-effective and straightforward chemical synthesis method to produce nickel oxide (NiO) nanoparticles decorated graphene oxide (GO) to improve the performance of a UV photodetector. The NiO/GO nanomaterial was prepared using a co-precipitation approach, followed by an annealing process at 400 °C. Various characterization techniques, including field emission scanning electron microscopy (FESEM), transmission electron microscopy, X-ray diffraction, and Raman spectroscopy, were performed to analyze the nanomaterial. The UV photodetector was electrically characterized to determine responsivity, detectivity, and temporal responses under both dark and UV-illuminated conditions at 375 nm. A detailed analysis of the current–voltage (I–V) curve was conducted to identify the presence of negative photoconductivity in the device. The results revealed an impressive photoresponse in the NiO/GO nanocomposite with a better responsivity of 2.17 A/W, a significant detectivity 2.3 × 1010 Jones, and good rise/fall times of 1.76/1.01 s under reverse bias conditions. These findings signify a novel trend for the next generation of photodetectors, incorporating multifunctional aspects. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three phase heterojunctions with ultrasmall Ru and Ni/NiO were constructed. • Interfaces collaborative optimization promotes alkaline hydrogen evolution. • The integrated AEM electrolyzer system requires 2.03 V at 1A cm−2. • A deep corrosion strategy through NaBH 4 prereduction was introduced. The rational design and optimization of heterogeneous interface for low loading noble metal HER eletrocatalysts to facilitate the upscaling of alkaline water/seawater electrolysis is highly challenging. Herein, we present a facile deep corrosion strategy induced by NaBH 4 to precisely construct an ultrasmall Ru nanoparticle-decorated Ni/NiO hybrid (r-Ru-Ni/NiO) with highly dispersed triple-phase heterostructures. Remarkably, it exhibits superior activity with only 53 mV and 70 mV at 100 mA cm−2 for hydrogen evolution reaction (HER) in alkaline water and seawater, respectively, surpassing the performance of Pt/C (109.7 mV, 100 mA cm−2, 1 M KOH). It is attributed to collaborative optimization of electroactive interfaces between well-distributed ultrasmall Ru nanoparticles and Ni/NiO hybrid. Moreover, the assembled r-Ru-Ni/NiO system just require 2.03 V at 1000 mA cm−2 in anion exchange membrane (AEM) electrolyzer, outperforming a RuO 2 /NF || Pt/C system, while exhibiting outstanding stability at high current densities. This study offers a logical design for accurate construction of interfacial engineering, showing promise for large-scale hydrogen production via electrochemical water splitting. [ABSTRACT FROM AUTHOR]

This study revealed the effective production of nickel oxide nanoparticles (NPs) using chelating agents derived from the leaves of Paulownia tomentosa plants and nickel (II) chloride hexahydrate (NiCl2⋅6H2O) as the precursor. Nickel oxide NPs (NiO NPs) have been successfully prepared by a green synthesis method using extracts of P. tomentosa leaves in water. The morphology and crystallinity of the NPs were investigated via X‐ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible spectroscopy (UV–vis), energy‐dispersive X‐ray analysis (EDX), Fourier transform infrared spectroscopy (FT‐IR) and thermogravimetric analysis (TGA). The formation behaviour of NiO NPs and the microstructural and physical properties of the resulting particles were studied. This study additionally investigated the antimicrobial, antibiofilm and cytotoxic effects of NiO NPs. Microstructurally uniform NiO NPs with a nanometre diameter were consistently produced using an eco‐friendly processing approach and exhibited a visible‐range transparency of 89%. The obtained SEM images confirmed the octahedral shape of the NPs. The NiO NPs acquired were found to have potent antimicrobial efficacy against all the other bacterial strains. As a result of their antibiofilm effects on pathogenic Escherichia coli and Pseudomonas aeruginosa bacteria, NiO NPs strongly inhibited these bacteria in a concentration‐dependent manner. In the cytotoxicity study of NiO NPs, a decrease in cell viability was shown to occur depending on the concentration of the cell lines used. [ABSTRACT FROM AUTHOR]

In this study, results on the effect of technological parameters of the nickel(II)‐oxide thin‐film deposition process, obtained through chemical vapor deposition in an argon–oxygen environment using bis‐(ethylcyclopentadienyl)‐nickel (EtCp)2Ni, on their electrochromic properties, are presented. It is shown that the films lose ability to electrochromic coloring in alkaline environments as their thickness increases up to 170 nm. The introduction of small ozone additions of 0.1 vol% O3 into the gas phase leads to a decrease in the NiO films deposition rate, the formation of a rougher layer with an average grain size up to 71.4 nm, capable of coloring in light brown. Additional cathodic treatment of NiO films at a potential of −0.8 V for 30 s in alkaline environments containing fullerene C60(OH)24 leads to the modification of the surface layer and the formation of NiO–C carbon‐containing nanocomposite coatings with enhanced contrast and the ability to retain the colored state after polarization is turned off, i.e., possessing optical memory properties. Using NiO–C nanocomposite and indium–tin–oxide films, which have opposite coloring mechanisms, in the structure of an electrochromic device allows for an increase in the grade of glass darkening, significantly reducing energy consumption, improving operational characteristics, and life span. [ABSTRACT FROM AUTHOR]

This paper presents a novel sensor for the electrochemical detection of ephedrine (EPD), a precursor compound used in the illicit production of amphetamines and related drugs. The sensor is based on a modified glassy carbon electrode (GCE) modified with nickel oxide/nitrogen-doped graphene oxide nanocomposite (NiO/NGO). The NiO/NGO nanocomposite was created hydrothermally and examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) methods. The successful nitrogen doping of graphene oxide (GO) and the anchoring of NiO nanoparticles on GO nanosheets in the nanocomposite are confirmed by all characterization studies. Measurements using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to assess the electrochemical performance of the NiO/NGO/GCE. The NiO/NGO/GCE showed good sensitivity, stability, and selectivity for EPD detection, with a linear range of 10–2580 µM and a detection limit of 0.09 µM. Moreover, the NiO/NGO/GCE was effectively used to calculate EPD in actual blood serum samples, yielding findings that were both reproducible and adequate (the recovery values varied from 98.80% to 99.40%, and the RSD values from 3.591% to 4.21%). The suggested biosensor provides an easy, quick, and affordable way to detect EPD in sports doping control. [ABSTRACT FROM AUTHOR]

X-ray Compton scattering experiments along with parallel first-principles computations were carried out on LiNiO2 to understand the effects of W doping on this cathode material for Li-ion batteries. By employing high-energy x rays exceeding 100 keV, an insight is gained into the fate of the W valence electrons, which are adduced to undergo transfer to empty O 2p energy bands within the active oxide matrix of the cathode. The substitution of W for Ni is shown to increase the electronic conductivity and to enhance the total magnetization per Ni atom. Our study demonstrates that an analysis of line shapes of Compton scattered x rays in combination with theoretical modeling can provide a precise method for an atomic level understanding of the nature of the doping process. [ABSTRACT FROM AUTHOR]

In this work, a new electrochemical sensor for the detection of the doping agent metoprolol (MTP) in food samples and bodily fluids is presented. The sensor's foundation is a nanocomposite made of polypyrrole (PPy) and nickel oxide nanoparticles (NiO NPs) on a glassy carbon electrode (GCE). Pyrole was electropolymerized to create the nanocomposite, and then NiO NPs were electrodedeposited on the GCE surface (NiO NPs/PPy/GCE). By combining the benefits of PPy with NiO NPs, this technique offers good electrocatalytic activity and a large surface area for analyte interaction. The nanocomposite was characterized using structural analyses such as scanning electron microscopy (SEM), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). These analyses revealed a network-like structure that improved the accessibility of the electrolyte ions and showed that the nanocomposite had been successfully deposited on the GCE surface. The electrochemical MTP sensor was examined using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) tests. The sensor's sensitivity was 0.03074 μA/μM, and it demonstrated a linear connection between the peak currents and the MTP concentrations (5–1600μM). The suggested sensor's limit of quantification (LOQ) and limit of detection (LOD) were determined to be 0.581 μM and 0.018 μM, respectively. The prepared urine sample produced acceptable recovery rates in the range of 98.40–99.86% in the real sample analyses, together with low relative standard deviation values (below 4.16%). In a similar vein, the prepared apple juice sample analysis revealed low relative standard deviation values (less than 4.28%) and respectable recovery rates ranging from 97.20 to 99.66%. The results showed low relative standard deviation values and good recovery rates, demonstrating the high precision and dependability of the suggested approach. [ABSTRACT FROM AUTHOR]

The growing market of printed electronics requires the development of new materials and processing technologies that enable the design of smart wearables, integrated sensors, and next-generation electronics. Against the backdrop of increasing material scarcity, these approaches must be resource-conserving and, at the same time, competitive with conventional technologies. As an alternative to nanoparticle-based inks currently used in printed electronics, another technology has been emerging in the last years that utilizes metal organic decomposition (MOD) inks, which are easy to fabricate and have a long shelf life. In this study, a method is presented that allows the direct formation of thin copper-nickel alloy films from a MOD ink. These alloys are preferably used for sensors like strain gauges as they exhibit a low thermal coefficient of resistivity (TCR). 250 nm thin alloy films are coated on glass substrates and thermally functionalized. In a conventional hot plate heat treatment under a nitrogen atmosphere, 10.2% bulk conductivity for a Cu55Ni45 alloy with a TCR of 8.3 × 10−5 K−1 is reached. X-ray diffraction analysis indicates the formation of a mixed crystal composed of nickel and copper atoms. A laser-based functionalization process is developed that allows the processing of Cu55Ni45 alloy films under ambient conditions without the formation of copper or nickel oxides. Laser-functionalized films exhibit 5.3% of the conductivity of bulk material. This study shows that metal alloy films can be fabricated directly from amine-based MOD inks. [ABSTRACT FROM AUTHOR]

This paper reports the onset of ferroelectricity in NiO by breaking the crystallographic symmetry with oxygen vacancies created by N doping. Nitrogen-doped NiO was grown at room temperature by RF sputtering of Ni target in Ar–O2–N2 plasma on silicon and fused silica substrates. The impact of the nitrogen doping of NiO on microstructural, optical, and electrical properties has been investigated. According to x-ray diffraction investigations, by increasing the N doping level in NiO, a transition from (002) to a (111) preferential orientation for the cubic NiO phase was observed, as well as a lattice strain relaxation, that is usually ascribed to structural defect formation in crystal. The x-ray diffraction pole figures the presence of a distorted cubic structure in NiO and supports the Rietveld refinement findings related to the strain, which pointed out that nitrogen doping fosters lattice imperfections formation. These findings were found to be in agreement with our far-infrared measurements that revealed that upon nitrogen doping a structural distortion of the NiO cubic phase appears. X-ray photoemission spectroscopy measurements reveal the presence of oxygen vacancies in the NiO film following nitrogen doping. Evidence of ferroelectricity in nitrogen-doped NiO thin films has been provided by using the well-established Sawyer–Tower method. The results reported here provide the first insights on oxygen-vacancy induced ferroelectricity in nitrogen-doped nickel oxide thin films. [ABSTRACT FROM AUTHOR]