Synthesis Of Metal Oxides Research Articles

Synthesis and catalytic application of nanostructured metal oxides and phosphates.

The design and development of new high-performance catalysts is one of the most important and challenging issues to achieve sustainable chemical and energy production. This Feature Article describes the synthesis of nanostructured metal oxides and phosphates mainly based on earth-abundant metals and their thermocatalytic application to selective oxidation and acid-base reactions. A simple and versatile methodology for the control of nanostructures based on crystalline complex oxides and phosphates with diverse structures and compositions is proposed as another approach to catalyst design. Herein, two unique and verstile methods for the synthesis of metal oxide and phosphate nanostructures are introduced; an amino acid-aided method for metal oxides and phosphates and a precursor crystallization method for porous manganese oxides. Nanomaterials based on perovskite oxides, manganese oxides, and metal phosphates can function as effective heterogeneous catalysts for selective aerobic oxidation, biomass conversion, direct methane conversion, one-pot synthesis, acid-base reactions, and water electrolysis. Furthermore, the structure-activity relationship is clarified based on experimental and computational approaches, and the influence of oxygen vacancy formation, concerted activation of molecules, and the redox/acid-base properties of the outermost surface are discussed. The proposed methodology for nanostructure control would be useful not only for the design and understanding of the complexity of metal oxide catalysts, but also for the development of innovative catalysts.

Alkaline Earth Metal Oxide Supported on Zeolite as a Heterogenous Basic Catalyst for Clean Fuel (Biodiesel) Production: A Mini Review

The depletion of fossil fuel reserves, worsening greenhouse gas effects, and global warming issues have driven the development of renewable energy sources, such as biodiesel. Biodiesel is as an alternative fuel to petrodiesel, typically produced through a transesterification reaction of triglycerides and alcohol in the presence of a catalyst. Alkaline earth metal oxide supported on zeolite are heterogeneous basic catalysts that are widely used in biodiesel synthesis. The addition of alkaline earth metal oxide to zeolite enhances the distribution of active sites, leading to an increase in catalytic activity. Zeolite is widely used as catalyst support due to its high surface area, good thermal stability, shape selectivity, and porous structure. This article presents recent developments in the synthesis and application of alkaline earth metal oxide supported on zeolite for transesterification reaction. The challenges and prospects of catalyst development are also discussed. This article aims to provide information and inspire the development of alkaline earth metal oxide supported on zeolite as a basic catalyst for biodiesel synthesis.

Cold plasma activated Ni0/Ni2+ interface catalysts for efficient electrocatalytic methane oxidation to low-carbon alcohols

To stabilize Ni0/Ni2+ during the CH4OR process, herein, we have successfully developed a general oxidation strategy for the direct synthesis of transition metal oxides by O2 cold plasma treatment of Ni0, including NiO, to generate a Ni0/Ni2+-on-Cu interface.

A comprehensive review on antibacterial analysis of natural extract-based metal and metal oxide nanoparticles.

Pharmaceutical,foodpacking,cosmetics,agriculture, energystorage devices widelyutilizemetal and metal oxide nanoparticles prepared via different physical and chemical methods. It resulted in the release of several dangerous compounds and solvents as the nanoparticles were being formed. Currently, Researchers interested in preparing nanoparticles (NPs) via biological approach due to their unique physiochemical properties which took part in reducing the environmental risks. However, a number of microbial species are causing dangerous illnesses and are a threat to the entire planet. Themetal and metal oxide nanoparticles played a significant role in the identification and elimination of microbes when prepared using natural extract. Its biological performance is thus also becoming exponentially more apparent than it was using in conventional techniques. Despite the fact that they hurt germs, their small size and well-defined shape encourage surface contact with them.The generation ofReactive Oxygen Species (ROS), weakens the bacterial cell membrane by allowing internal cellular components to seep out. The bacterium dies as a result of this. Numerous studies on different nanoparticles and their antibacterial efficacy against various diseases are still accessible. The main objective of the biogenic research on the synthesis of key metals and metal oxides (such as gold, silver, titanium dioxide, nickel oxide, and zinc oxide) using variousplant extracts is reviewedin this study along with the process of nanoparticle formation and the importance of phytochemicals found in the plant extract.

Moringa oleifera Leaves: A Proficient Biosynthetic Source of Myriad Nanoparticles Pertaining Biomedical Importance

The advent of nanotechnology has blurred the boundaries between various fields. Development of newer, efficient, and sustainable approaches for nanomaterial synthesis has become the primary focus of research in recent years. The utilization of biological molecules as matrices for nanoparticle synthesis is increasing, with bacteria, fungi, plants, agrowaste, being common choices. Among them plant extracts are favoured biological source due to their widespread availability and diverse range of primary and secondary metabolites. These antioxidant metabolites possess reducing properties, indicating the potential for plant extracts to synthesize nanoparticles with enhanced characteristics. Moringa oleifera is a perennial, fast growing very popular plant in Asia. Since ancient times it is an important source of natural phytochemicals employed as food and herbal medicine. Moringa leaves have high number of phytochemicals like flavonoids, saponins, tannins, phenolic acids, proteins, calcium, iron, vitamins, essential amino acids, omega fatty acids and antioxidants. These facilitates eco-friendliness, and cost-effectiveness for large-scale production of nanomaterials. So far, several parts have been utilised for biosynthesis such as stem, bark, seed, fruit, and leaf. Leaves are highly exploited among all other parts for synthesis of several metal (gold, silver, copper,), metal oxide (titanium, zinc, iron) and other nanoparticles. During biosynthesis process, extracted phytochemicals are added to solutions containing metal salts. They serve as both reducing and stabilizing agents for metal ions imparting biomedical functionalities. This review presents, Moringa oleifera mediated myriad nanoparticles and their role in various applications with special focus to healthcare and biomedical field.

Synthesis and Characterization of Selected Metal Oxide Nanoparticles

In the present study, oxide nanoparticles of copper, cobalt, iron and zinc metals have been synthesized using a chemical co-precipitation approach. This gives a large scale production of metal oxide nanoparticles. The structural properties of the synthesized metal oxide nanoparticles were studied using X-ray diffraction (XRD). The XRD result reveals the crystalline nature of the metal oxide nanoparticles. Additional, scanning electron microscopy (SEM) was also performed to study the morphology of the selected four metal oxide nanoparticles. SEM micrograph showed the spherical morphology of as prepared CuO, CO2O3, Fe2O3 and ZnO nanoparticles also they are interspersed with each other.

From E-Waste to High-Value Materials: Sustainable Synthesis of Metal, Metal Oxide, and MOF Nanoparticles from Waste Printed Circuit Boards.

The exponential growth of electronic waste (e-waste) has raised significant environmental concerns, with projections indicating a surge to 74.7 million metric tons of e-waste generated by 2030. Waste printed circuit boards (WPCBs), constituting approximately 10% of all e-waste, are particularly intriguing due to their high content of valuable metals and rare earth elements. However, the presence of hazardous elements necessitates sustainable recycling strategies. This review explores innovative approaches to sustainable metal nanoparticle synthesis from WPCBs. Efficient metal recovery from WPCBs begins with disassembly and the utilization of advanced equipment for optimal separation. Various pretreatment techniques, including selective leaching and magnetic separation, enhance metal recovery efficiency. Green recovery systems such as biohydrometallurgy offer eco-friendly alternatives, with high selectivity. Converting metal ions into nanoparticles involves concentration and transformation methods like chemical precipitation, electrowinning, and dialysis. These methods are vital for transforming recovered metal ions into valuable nanoparticles, promoting sustainable resource utilization and eco-friendly e-waste recycling. Sustainable green synthesis methods utilizing natural sources, including microorganisms and plants, are discussed, with a focus on their applications in producing well-defined nanoparticles. Nanoparticles derived from WPCBs find valuable applications in drug delivery, microelectronics, antimicrobial materials, environmental remediation, diagnostics, catalysis, agriculture, etc. They contribute to eco-friendly wastewater treatment, photocatalysis, protective coatings, and biomedicine. The important implications of this review lie in its identification of sustainable metal nanoparticle synthesis from WPCBs as a pivotal solution to e-waste environmental concerns, paving the way for eco-friendly recycling practices and the supply of valuable materials for diverse industrial applications.

Solution-Based Synthesis of Cathode Materials for Lithium Ion Batteries

Electrochemical energy storage is expected to make an important contribution to combating global climate change, e.g. via electric vehicles and stationary storage. Currently, lithium-ion batteries are the most prominent candidate for rechargeable batteries to be used in this respect. However, performance of lithium-ion batteries is strongly influenced by the active material at the cathode side, which is often a complex multi-metal oxide. Such a material's properties are dictated by the fabrication method. The design of an appropriate synthesis strategy is then logically also aimed at optimal material properties. However, the design strategy should also take into account green chemistry principles, such as atom economy and energy efficiency. Solution-based routes towards (multi)metal oxide synthesis provide a large diversity of routes and therefore a strong versatility in their design. In this contribution, two groups of routes will be discussed: aqueous solution-gel and coprecipitation routes. The aqueous solution-gel route encompasses three stages: precursor solution synthesis, in which the metal ions are stabilized by complexation with carboxylate ligands, gelation to form an amorphous precursor gel in which the metal ions are homogeneously mixed, and decomposition into the final metal oxide. In this route, precipitation is to be avoided, since it would introduce inhomogeneities. In contrast, the coprecipitation route is entirely based on the formation of insoluble solid precipitates, which can be further transformed in a solid state reaction into lithiated compounds. Whereas solution-gel is ideally suited for complex metal oxides with a large number of metal ions, coprecipitation of many different metal ions at the same time can be challenging. On the other hand, the atom efficiency of the latter can be very high which is attractive for upscaling. Certainly, both of these routes have a high versatility because of the flexibility in compositions (starting products, solvents, ...) and conditions (temperature, time, ...) during the synthesis.In this presentation, an overview will be given of the application of these synthesis routes to the synthesis and/ or surface modification of various cathode materials for lithium ion batteries, which are of general interest and are ranging from Ni-rich compositions of NMC (NMC622), to lithium manganese rich NMC and to Co-free compositions such as LNMO and Li rich LMO. First, the classic NMC 622 is surface modified by a TiOx via a sol-gel route, leading to the formation of core-shell structured particles. The presence of TiOx improved the rate performance and electronic conductivity of the cathode material, and led to a higher initial coulombic efficiency and lower ageing rates in full cells with LTO. Furthermore, layered Li-rich/Mn-rich (LMR-)NMC, which is interesting because of its remarkably high specific discharge capacity was synthesized by two different routes, solution-gel and coprecipitation. It was shown that the solution-gel material in this case had a retarded voltage fade but larger capacity fade than the coprecipitated material. This was correlated to differences in particle morphology and the presence of Ni-enriched spinel-type surface layer. Furthermore, the effect of Sn4+ substitution in the LMR-NMC was investigated. The solubility of Sn4+ substituting for Mn4+ turned out to be a limiting factor here, and could not prevent the voltage fade sufficiently. Finally, we turned to Co-free cathode compositions. LiNi0.5Mn1.5O4-delta was prepared by an aqueous solution-gel route, which allowed to tune the particle size (a few µm versus 70 µm) and morphology. This led to optimized initial discharge capacity and its retention. Finally, Ti4+ substituted Li2MnO3 was synthesized as well via an aqueous solution-gel method. The substitution was shown to improve the structural stability, and galvanostatic cycling hinted at a delayed oxygen release during the first 10 cycles, however, followed by pronounced oxygen redox activity.In conclusion, solution-based routes are highly versatile and provide many opportunities to synthesize cathode materials for lithium ion batteries.

Solvent-pair surfactants enabled assembly of clusters and copolymers towards programmed mesoporous metal oxides

Organic-inorganic molecular assembly has led to numerous nano/mesostructured materials with fantastic properties, but it is dependent on and limited to the direct interaction between host organic structure-directing molecules and guest inorganic species. Here, we report a “solvent-pair surfactants” enabled assembly (SPEA) method to achieve a general synthesis of mesostructured materials requiring no direct host-guest interaction. Taking the synthesis of mesoporous metal oxides as an example, the dimethylformamide/water solvent pairs behave as surfactants and induce the formation of mesostructured polyoxometalates/copolymers nanocomposites, which can be converted into metal oxides. This SPEA method enables the synthesis of functional ordered mesoporous metal oxides with different pore sizes, structures, compositions and tailored pore-wall microenvironments that are difficult to access via conventional direct organic-inorganic assembly. Typically, nitrogen-doped mesoporous ε-WO3 with high specific surface area, uniform mesopores and stable framework is obtained and exhibits great application potentials such as gas sensing.

A Review on Microwave Assisted Synthesis of Transition Metal Oxides and their Potent Application as Supercapacitors

AbstractPreparation of transition metal oxides and mixed metal oxides via a microwave‐assisted method that permits processes to be completed in a quicker reaction time with the formation of homogenous and well‐dispersed nanoparticles. Recently, due to the environmentally friendly nature of this technique, it has become an important approach to green chemistry. The major advantage of microwave‐assisted synthesis includes clean, fast, efficient, less time‐consuming, highly accelerated rate, high yield, and an economic method. In this review, we have discussed the process of microwave synthesis and also compared this with other synthetic methods. A discussion of transition metal oxides in groups was performed where we have discussed their synthetic route and reaction conditions along with the effect on morphology and other properties. Additionally, the application of transition metal oxides as supercapacitors was also discussed. Since then, researchers have gained a lot of interest in transition metal oxides as energy storage devices due to their low‐cost, energy efficient, long cycle life, and improved electrical, thermal, and chemical stability, variable oxidation states and excellent redox properties. However, they cannot meet the need for high‐performance energy devices due to their low conductivity.

Single-Step Formation of Metal Oxide Nanostructures Wrapped in Mesoporous Silica and Silica–Niobia Catalysts for the Condensation of Furfural with Acetone

The integration of metal oxide nanomaterials with mesoporous silica is a promising approach to exploiting the advantages of both types of materials. Traditional synthesis methods typically require multiple steps. This work instead presents a fast, one-step, template-free method for the synthesis of metal oxides homogeneously dispersed within mesoporous silica, including oxides of W, Ti, Nb, Ta, Sn, and Mo. These composites have tunable metal oxide contents, large surface areas, and wide mesopores. The combination of Nb2O5 nanoparticles (NPs) with SiO2 results in an increased surface area and a larger number of acid sites compared to pure Nb2O5 NPs. The surface texture and acidity of the silica–niobia composites can be tuned by adjusting the Nb/Si molar ratio. Moreover, the silica provides protection to the niobia NPs, preventing sintering during thermal treatment at 400 °C. The silica–niobia materials exhibit superior performance as catalysts in the aldol condensation of furfural (Fur) with acetone compared to pure niobia, leading to an up to 62% in product yield. Additionally, these catalysts show remarkable stability, retaining their performance over multiple runs. This work demonstrates the potential of the proposed synthesis approach for preparing more sustainable, high-performance, durable, and stable nanoscale metal oxide-based catalysts with a tunable composition, surface area, and active site density.

Back to basics: synthesis of metal oxides

Back to basics: synthesis of metal oxides

Sonocatalytic degradation of nitrobenzene with metal oxide clay nanocomposites

AbstractBACKGROUNDThe presence of a wide range of persistent toxic organic pollutants in industrial effluents poses a serious threat to human and environmental health, emphasising the necessity for developing cost‐effective methods for treating toxic effluents. This study focuses on the synthesis, characterization and evaluation of metal oxide [iron (Fe), copper (Cu) and zinc (Zn)]‐doped clay composite for the sonocatalytic degradation of nitrobenzene (NB) in the presence of ultrasound.RESULTS AND CONCLUSIONSAmong the metal oxides studied, Cu and Fe oxide‐modified clay performed better in the degradation of NB (~99% in the presence of air) compared to a ZnO/clay composite. Process optimization studies were carried with CuO/clay composite at different pHs (2.5–11.5), feed concentrations (50–200 mg L−1) and catalyst loadings (0.25–1.0 g L−1). Neutral pH conditions and higher catalyst loadings of 1 g L−1 were found to be optimal for the efficient degradation of 50 ppm NB. Among the scavengers tested, ethylenediamine tetra acetic acid exhibited strong scavenging effects, resulting in reduced NB degradation compared to isopropyl alcohol and tin tetrachloride, regardless of the scavenger concentration (0.5 and 40 mmol L−1). The catalyst was found to be sufficiently stable for up to four cycles under identical conditions. Additionally, these materials were found to be effective in the degradation of other pollutants [Terephthalic acid, Rhodamine‐B, Ciprofloxacin]. These findings contribute to the development of cost‐effective strategies for the treatment of industrial effluents, reducing the risks posed to both the environment and human health. © 2023 Society of Chemical Industry (SCI).

Hard acid soft base (HSAB) guided morphology engineered copper oxides for efficient photocatalytic degradation of textile effluent under visible light

This study demonstrates the synthesis of morphology guided copper oxide nanostructures (CuO) based on Hard Acid and Soft Base concept (HSAB) and their influence on photocatalytic activity under visible light. Herein, we adopted simple chemical bath approach for the synthesis of CuO nanomaterial with different morphologies by using various precursors of copper such as copper nitrate, copper sulfate and copper chloride. The as-synthesized samples were characterized by means of various analytical techniques namely X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), UV–Visible absorption spectroscopy (UV–VIS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) and Brunauer-Emmett-Teller surface area analysis (BET). FE-SEM analysis revealed that the as-synthesized CuO, displayed precursor depended morphologies, including horse mane, honeycomb, and aggregated cubic shaped morphologies. Notably, horse mane like copper oxide (henceforth referred to as CuO-1) produced using copper nitrate as a precursor, showed 92.18% towards methylene blue (MB) dye degradation within a span of 180 min under visible light illumination. Thus this study opens the door for the synthesis of other metal oxides with distinct morphologies that could be used for potential photocatalytic applications.

Fabrication of Ni-Cr-FeOx ceramic supercapacitor electrodes and devices by one-step electric discharge ablation

This investigation addresses the need in the development of a facile, low-cost and computer-aided design method to fabricate ceramic supercapacitors, based on patterned metal oxide films. It is motivated by the promising advantages of planar electrode arrangement for the fabrication of ceramic supercapacitors operating at extremely high charge-discharge rates. Herein, one-step electric discharge ablation (EDA) technique is developed for fabricating Ni-Cr-FeOx electrodes using commercial 304 stainless steel current collectors for the first time. The binder-free, noble materials-free, toxic chemical-free and conductive additives-free Ni-Cr-FeOx based in-plane microsupercapacitors (IMSC) are fabricated by the EDA technique. The obtained IMSC delivers a high areal capacitance of 38.3 mF cm−2 at 1 mV s−1 and shows superior capacitive behavior at an ultrahigh scan rate of 152,000 mV s−1, which is >760 times higher than the reported values for ceramic metal oxide based electrodes in the literature. This one-step, low-cost, environmental friendly, and automatic fabrication method is promising for the scale-up synthesis of various ceramic metal oxides and fabrication of supercapacitor devices.

Biogenic synthesis of ZnO and Al2O3 nanoparticles using Camellia sinensis and Origanum vulgare L. leaves extract for spectroscopic estimation of ofloxacin and ciprofloxacin in commercial formulations.

The current study describes the biogenic synthesis of two metal oxides zinc oxide (ZnO), aluminum oxide (Al2O3) nanoparticles using Camellia sinensis, and Origanum vulgare L. leaves extract, respectively. The synthesized metal oxide nanoparticles were investigated using spectroscopic and microscopic techniques to confirm the formation of their nanostructures. Accurate and precise spectrofluorometric probes were proposed for the quantification of Ofloxacin (OFX) and Ciprofloxacin (CPFX) in their bulk and commercial formulations. The extraordinary properties of Zinc oxide and aluminum oxide nanoparticles (ZnONPs and Al2O3NPs) enhance the fluorescence intensity in the presence of 0.5 mL and 1.0 mL of sodium dodecyl sulfate (SDS, 1.0% w/v) as organizing agent for the detection of OFX and CPFX, respectively. The optical detection of both drugs at λex/em range 250-700 nm displayed linearity with a main correlation coefficient >0.999 at 1-300 (OFX-SDS-ZnONPs) and 0.5-100 (OFX-SDS-Al2O3NPs) ng mL-1,10-400 (CPFX-SDS-ZnONPs) and 0.1-50 (CPFX-SDS-Al2O3NPs) ng mL-1. The detection and quantification limits were found to be 0.04, 0.03, and 0.02, 0.04 ng mL-1, 0.13, 0.10, and 7.24, 0.09 ng mL-1 for the above-mentioned fluorescence systems, respectively. The suggested spectrofluorometric probes were validated and potentially applied for the estimation of OFX and CPFX in their bulk and commercial formulations.

Metal oxide- and metal-loaded mesoporous carbon for practical high-performance Li-ion battery anodes

The rapidly expanding Li-ion battery market needs new materials that can satisfy the increasing energy storage demand. Metal oxides and some metals such as tin are viable alternatives to graphite as Li-ion battery anodes, but their low conductivity and large volume change during cycling impose severe challenges that need to be overcome. Confinement of metal oxide and metal nanomaterials within mesoporous carbon (MC) is an effective strategy in this regard, but complex synthesis and nanoparticle aggregation have hindered its application. Herein, we report a facile, scalable and generalized methodology for the room-temperature synthesis of metal oxide and metal nanoparticles within a MC host. The approach has been successfully applied to achieve uniform distribution and prevent aggregation of a large variety of metal oxide and metal nanomaterials in MC support. These nanocomposites were screened as Li-ion battery anodes, and the optimal candidates were shown to be superior to previously reported systems. Our synthesis method was scaled up using commercial MC. The nanocomposites were validated in a high-loading electrode (4 mg/cm2) with a practical voltage range (< 2 V vs. Li+/Li), showing impressive initial Coulombic efficiency (> 100%), and excellent stability (∼ 500 mAh/g after 250 cycles at 0.2 A/g), which was 1.5–2x better than commercial graphite at the same testing conditions. The facile nature, universality and versatility of our approach make it possible to load various metal oxide and metal nanomaterials within different types of MC. These nanocomposites would be of significant interest to different fields, such as energy storage and conversion, sensing, and catalysis.

The ultralong Mo4O11 nanoribbons: Ultrasonic synthesis and topotactic transformation toward high-performance sodium-ion batteries

The design and synthesis of two-dimensional layered transitional metal oxides (TMOs) have been of great interest for their potential application in sodium-ion batteries (SIBs), due to the advantages such as multivalent ions and tunable interlayer spacing. However, achieving a well-defined crystal structural topology and geometric morphology in TMOs still remains a significant challenge, particularly in tailoring their polyhedral structures. Herein, the ultralong Mo4O11 nanoribbons (Mo4O11-NR) were prepared by a simple aniline-assisted sonochemical method for the first time. The resulting nanoribbons possess a unique tunnel structure and exhibit topologically frustrated arrangements of MoO6 octahedra and MoO4 tetrahedra. When used as anodes for SIBs, multielectron redox reactions of Mo4O11-NR allow for high-capacity energy storage. The buffered volume expansion of the nanoribbons accommodates the strain that occurs during cycling, thereby boosting cycling stability. The topologically frustrated arrangements of the polyhedra further contribute to the efficient storage and transfer of ions and electrons. As a result, Mo4O11-NR anode achieves a reversible specific capacity of 101 mA h g−1 after 2,000 cycles, when subjected to a high current density of 5 A g−1. This exceptional performance highlights the potential of Mo4O11-NR material as an advanced anode material for high-power devices.

Construction of novel potentiometric sensors modified with biogenically synthesized metal oxide nanoparticles for sensitive detection of the opioid agonist-antagonist nalbuphine hydrochloride in its injection

Novel and sensitive potentiometric sensors were described for the assay of nalbuphine HCl (NBP) in authentic powder and injection samples. The developed sensors were modified with alumina nanoparticles (Al2O3NPs) and copper oxide nanoparticles (CuONPs). The nanoscale materials were synthesized using the extract of Salvia officinalis leaves in an environmentally friendly manner. The synthesized metal oxides were fully confirmed by various analytical techniques. Scanning electron microscope confirmed the morphology of nanosized materials with even distribution and particle size of 55.07 ± 4.15 and 59.48 ± 4.50 nm for Al2O3NPs and CuONPs, respectively. The modified sensors were prepared in three different steps. Nalbuphine hydrochloride was mixed with phosphomolybdic acid to prepare the sensor material nalbuphine phosphomolybdate (NBP-PM). It was then mixed with polyvinyl chloride in the presence of o-nitrophenyl ether and metal oxide nanoparticles to form the membrane matrix. Finally, a copper wire was coated with the sensing material. Excellent potentials of 1.0 × 10−8-1.0 × 10−2 and 1.0 × 10−9-1.0 × 10−2 mol L−1 were measured with lower assay limits of 4.8 × 10−9 and 5.0 × 10−10 mol L−1. The average detection % were 99.28 ± 0.58% and 99.52 ± 0.28% for NBP-PM-Al2O3NPs and NBP-PM-CuONPs, correspondingly. The suitability of the described sensors was investigated in terms of various validation criteria, and the modified sensors exposed excellent applicability and insurance for the quantification of nalbuphine hydrochloride in its bulk samples and injections compared with another standard sensor. It is obvious that the developed NBP-PM-Al2O3NPs and NBP-PM-CuONPs will serve as suitable sensors for the determination of NBP.

Conformal Coverage of ZnO Nanowire Arrays by ZnMnO3 : Room-temperature Photodeposition from Aqueous Solution.

Compositionally and structurally complex semiconductor oxide nanostructures gain importance in many energy-related applications. Simple and robust synthesis routes ideally complying with the principles of modern green chemistry are therefore urgently needed. Here we report on the one-step, room-temperature synthesis of a crystalline-amorphous biphasic ternary metal oxide at the ZnO surface using aqueous precursor solutions. More specifically, conformal and porous ZnMnO3 shells are photodeposited from KMnO4 solution onto immobilized ZnO nanowires acting not only as the substrate but also as the Zn precursor. This water-based, low temperature process yields ZnMnO3 /ZnO composite electrodes featuring in 1 M Na2 SO4 aqueous solution capacitance values of 80-160 F g-1 (as referred to the total mass of the porous film i. e. the electroactive ZnMnO3 phase and the ZnO nanowire array). Our results highlight the suitability of photodeposition as a simple and green route towards complex functional materials.