Addition Of Metal Oxides Research Articles

Review on the preparation of electrolyte thin films based on cerate-zirconate oxides for electrochemical analysis of anode-supported proton ceramic fuel cells

Proton ceramic fuel cells (PCFCs) are a better alternative to the combustion-based electrical generators because of their high energy conversion efficiency and low carbon emission at relatively low operating temperatures. The electrochemical performance of PCFCs in terms of conductivity, cycling stability, and power density is heavily influenced by the morphological and compositional characteristics of the electrolyte materials. These characteristics can be controlled during the synthesis and fabrication processes. Microstructural modification of the proton ceramic electrolyte can further optimize the electrochemical performance and enhance the efficiency of PCFCs. The well-known electrolyte materials derived from cerate–zirconate ceramic perovskite-type oxides show incredibly high proton conductivity in hydrogen- and/or water-containing atmospheres. This review aims to discuss the influence of electrolyte synthesis and fabrication techniques on the electrochemical properties of PCFCs. Results and findings from different studies are explored and analyzed to examine the effects of grain size, sample density, sintering temperatures, and the addition of metal oxides on the electrolyte performance of PCFCs. • Electrolyte based on cerate-zirconate oxides for PCFCs application is reviewed in the context of fabrication techniques. • Selection of the aright fabrication technique can produce the required microstructure of the targeted proton conductor. • The microstructure of the electrolytes has remarkable impacts on the PCFCs performance.

Composite TiO2-based photocatalyst with enhanced performance.

TiO2 is the most studied photocatalyst because of its non-toxicity, chemical stability, and low cost. However, the problem of TiO2 is its low activity in the visible region of the spectrum. In this study, we focused on the preparation of composite photocatalytic materials with altered light absorption properties. TiO2 P25 and various metal oxides were mechanically joined by ball-milling and immobilized on glass plates. The prepared samples were evaluated based on their ability to degrade NO in gas phase. The formation of undesirable byproducts was also investigated. Four best performing composites were later chosen, characterized, and further evaluated under various conditions. According to their performance, the metal oxide additives can be divided into three groups. P25/Fe2O3 showed the most promising results-an increase in overall deNOx activity under modified ISO conditions and altered selectivity (less NO2 is formed) under both simulated outdoor and simulated indoor conditions. On the other hand, P25/V2O5 composite showed negligible photocatalytic activity. The intermediate group includes P25/WO3 and P25/ZnO photocatalysts, whose performances are similar to those of pristine P25.

VAPOR-PHASE OXIDATION OF 2-METHYLPYRIDINEON V-Zr-O-CATALYSTS MODIFIED WITH TIN AND NIOBIUM OXIDES

Vapor-phase catalytic oxidation of pyridine alkyl derivatives is an effective method for obtaining a variety of physiologically active substances that are widely used in practice, as well as for the synthesis of solvents, starting materials for the production of dyes, herbicides, etc. For the process, a cheap oxidizing agent is used -atmospheric oxygen. Of great importance is the choice and creation of an active and selective process catalyst. Basically, the oxidation processes are carried out in the presence of catalysts based on vanadium oxide with the addition of transition metal oxides. The aim of the work.Study of the behavior of V-Zr-O catalysts modified with tin and niobium oxides in the vapor-phase oxidation of 2-methylpyridine. Metodology. Vapor-phase oxidation of 2-methylpyridine was carried out in a flow-type reactor simulating an element of an industrial contact apparatus. The reaction products were analyzed by chromatographic method. Results and disscution. It was shown that the component composition of the contact determines the catalytic action in the studied process, affecting not only the activity of the catalyst, but also the composition of the reaction products. By varying the conditions of the vapor-phase catalytic oxidation of 2-methylpyridine, such as temperature, the molar ratio of the initial substance:О2:Н2О, it is possible to obtain both oxygen-containing derivatives (pyridine-2-aldehyde and picolinic acid) and pyridine, a product of oxidative demethylation. Conclusion.It has been established that pyridine, which is one of the important products of the vapor-phase oxidation of 2-methylpyridine, can be obtained in 85.3% yield on a V-Zr-O catalyst modified with niobium oxide.

Heavy metal oxide added glassy portable containers for nuclear waste management applications: In comparison with reinforced concrete containers

This study aimed to investigate the protective properties of Bi2O3 heavy metal oxide-doped glassy portable containers and the effect of reinforcement amount on these properties using the MCNPX (version 2.6.0) general-purpose Monte Carlo code. Accordingly, 60Co and 137Cs radioisotopes were defined as point isotropic radioactive sources to be transported with the newly designed containers. Four containers with different heavy metal oxide additives varying between 5% and 20% were designed and the deposited energy (MeV/g) values in the air were calculated for both 60Co and 137Cs radioisotopes. According to the findings of the first phase of the investigation, the sample (S4) with a 20% Bi2O3 additive ratio showed the highest protective properties and the least amount of deposited energy amount in the air. In the second and benchmarking phase of the investigation, we compared the amount of deposited energy in the air for the superior S4 glass container and a concrete container with a high amount of bitumen additive. The findings demonstrated that the S4 portable glass container with a 20% Bi2O3 reinforcement provided significantly lower deposited energy in the air and therefore greater nuclear safety than the concrete container. Heavy metal oxide-doped glass may be considered a viable choice for nuclear waste management and transportation operations due to its nuclear safety properties and superior physical, optical, and mechanical capabilities in comparison with concrete.

Chitosan/waste glass composite as new material for copper removal from contaminated water

Chitosan/waste glass composite material with different mass fractions was synthesized via sample mixing and pressing route. Synthesized materials were characterized and their structure was investigated through different characterization techniques. X-ray diffraction analysis reveals the amorphous nature of studied base materials and their blends without any evidence for crystalization. Examined glass powder composition was found to be mainly soda-lime-silica with minor metal oxide additives correlated to the color of the glass. The stability and hydrophilicity of the investigated composite material were investigated using a swelling rate test. Obtained data shows that synthesized composite material can act as an adsorbent of copper ions through both chemical and physical interactions. The investigated composite has a broad range of antibacterial activity against both gram-positive and gram-negative bacteria, as well as a growing adsorption capacity for Copper (II) ions, indicating that it might be used in the copper removal process from aqueous solutions. Proposed material can be suggested to be used for other metal ions based on the condition of the initial water solution and environmental remediation.

Catalytic role of binary oxides (CuO and Al2O3) on hydrogen storage in MgH2

AbstractHydrogen sorption characteristics of magnesium hydride (MgH2) were enhanced by ball milling for 12 h under an inert atmosphere with the addition of 20 wt% Al2O3 and as prepared CuO. X‐ray diffraction (XRD) characterization and thermal gravimetric analyzer coupled with a mass spectrometer (TGA‐MS) of the ball milled samples were carried out to determine the H2 sorption reactions. Additionally, XRD data were analyzed using Rietveld method to identify the crystallographic properties. Ball milled MgH2 with β and γ allotrope mixtures were found with broad peaks in XRD indicating the as prepared samples are amorphous and strain, alongside bare additives. H2 sorption in MgH2 is greatly enhanced by the presence of CuO and Al2O3 binary oxides. TGA experiment demonstrated fast desorption kinetics for ball milled samples with the oxide additives. Particularly, MgH2 milled with CuO showed a more remarkable effect on desorption kinetics rather than Al2O3. It takes less than 10 min to desorb more than 5 wt% H2 at 623 K. The activation energy of H2 desorption was estimated for the mixtures by Kissinger method and the lowest value (65 kJ mol−1) was obtained for the MgH2/CuO mixture. A kinetic model has been proposed in the context to illustrate the complex mechanism of dehydrogenation of MgH2 with the additives. Finally, the addition of metal oxides influences H2 sorption characteristics of MgH2 through lowering the activation energy and reducing the waste of energy for diffusing the thin layer of Mg that creates a pathway to store H2 within the system.

A Sequenced Study of Improved Dielectric Properties of Carbon Nanotubes and Metal Oxide-Reinforced Polymer Composites.

Polymers have gained attraction at the industrial level owing to their elastic and lightweight nature, as well as their astonishing mechanical and electrical applications. Their scope is limited due to their organic nature, which eventually leads to the degradation of their properties. The aim of this work was to produce polymer composites with finely dispersed metal oxide nanofillers and carbon nanotubes (CNTs) for the investigation of their charge-storage applications. This work reports the preparation of different polymeric composites with varying concentrations of metal oxide (MO) nanofillers and single-walled carbon nanotubes (SWCNTs). The successful synthesis of nanofillers (i.e., NiO and CuO) was carried out via the sonication and precipitation methods, respectively. After, the smooth and uniform polymeric composite thin films were prepared via the solution-casting methodology. Spectroscopy and diffraction techniques were used for the preliminary characterization. Scanning electron microscopy was used to check the dispersion of carbon nanotubes (CNTs) and MOs in the polymer matrix. The addition of nanofillers and carbon nanotubes (CNTs) tuned the bandgap, reduced the strain, and enhanced the elastic limit of the polymer. The addition of CNT enhanced the mechanical strength of the composite; however, it increased the conductivity, which was tuned by using metal oxides. By increasing the concentration of NiO and CuO from 2% to 6% bandgap of PVA, which is 5–6 eV reduced to 4.41 and 4.34 eV, Young’s moduli of up to 59 and 57.7 MPa, respectively, were achieved. Moreover, improved dielectric properties were achieved, which shows that the addition of metal oxide enhances the dielectric behavior of the material.

Physical, structural and radiation absorption characteristics for some Eu3+ doped heavy metal oxide phosphate glasses

Europium doped phosphate glasses were synthesized by employing melt-quench technique. Structural characterizations were determined from XRD and FTIR Spectroscopy. XRD patterns revealed the amorphous structure of the synthesized glasses. The formation of phosphate structural units were confirmed from FTIR analysis. The effect of addition of heavy metal oxide (HMO) on physical properties viz density (ρ), molar volume (Vm), oxygen molar volume (Vo), oxygen packing density (OPD) and Polaron radius (rp) were studied. The ρ and Vm of the synthesized glasses shows an increasing trend with an incorporation of HMOs as per their atomic number. The mechanical characterizations viz. packing factor (Vt), total dissociation energy per unit volume (Gt), Young’s modulus (E), Bulk modulus (K), Shear modulus (S), Poisson’s ratio (μ), longitudinal modulus (L) and hardness (H) of the synthesized glasses were obtained using Makishima and Mackenzie (MM) model. Photon interaction characterizations for the glasses were obtained using Monte Carlo simulation code FLUKA and also using WinXCom database. The neutron shielding characteristics for the glasses were obtained for thermal as well as fast neutrons. Further, the effect of HMOs on different properties have been discussed to check the feasibility of glasses in radiation shielding and sensing applications.

Interaction of zirconia with magnesium hydride and its influence on the hydrogen storage behavior of magnesium hydride

This study demonstrates how zirconia additive transforms to zirconium hydride and substantially lowers the dehydrogenation temperature of magnesium hydride. We prepared MgH2+xZrO2 (x = 0.125 and 0.5) powder samples reacted for 15 min, 1 h, 5 h, 10 h, 15 h, 20 h and 25 h, and monitored the phase changes at each stage of the reaction. Differential scanning calorimetry (DSC) study provides the first crucial evidence regarding the chemical transformation of zirconia. Subsequently, detailed additional sample testing by X-ray diffraction (XRD), energy dispersive x-ray spectroscopy and confocal Raman microscopy provide strong supports that low temperature dehydrogenation of magnesium hydride is a result of formation of an active in situ product (zirconium hydride). This observation is validated by the negative Gibbs free energy values obtained for the formation of zirconium hydride over a broad working temperature range of 0–600 °C. Scanning electron microscopy (SEM) results prove the high dispersion of tiny nanoparticles all across the surface after the chemical interaction between MgH2 and ZrO2 and atomic force microscopy (AFM) study further proves that objects with grain sizes of ∼10 nm are abundant throughout the scanned surfaces. These observations reiterate that better metal oxide additives interact with MgH2 and results to the evolution of highly active insitu nanocatalysts.

Coal char gasification for co-production of fuel gas and methane decomposition catalysts

Partial gasification of coal char was conducted with addition of metal oxides for co-production of fuel gas and methane decomposition catalysts. Effect of the metal composition (Ni, Co and Fe based mono- or bi-metals) was investigated on the fuel gas production and the resultant catalyst surface and textural properties, morphology and performance in catalytic methane decomposition (CMD). Besides H2-rich fuel gas production (the combustion energy up to 11.03–23.42 MJ/kgchar) from the gasification, the gasification residue can directly serve as the effective and efficient catalyst for CMD. The Fe and Fe–Co composite oxides were found to be better among the mono- and bi-metallic oxides for the fuel gas production during the gasification, respectively. The Ni-based mono-/bi-metallic catalysts could display high and stable methane conversion (up to 80%) during the 600-min CMD test at 850 °C. Promotional role of the second metal in CMD was discussed on the carbon diffusion, metal mobility and reducibility, formation and growth of the deposited carbons. The formed carbon morphology after CMD was analyzed based on the Kirkendall effect and Tammann temperature and further correlated to the potential catalyst deactivation.

Screening of biohydrogen production based on dark fermentation in the presence of nano-sized Fe2O3 doped metal oxide additives

Increasing the biohydrogen production efficiency through the dark fermentation process has become the biggest challenge in recent years. We aim to enhance biohydrogen production yield by adding nano-sized iron oxide doped metal oxides prepared by the wet impregnation method. Biohydrogen production in the presence of additives was evaluated by the screening of (i) type (Fe 2 O 3 @Al 2 O 3 , Fe 2 O 3 @ZrO 2 , and Fe 2 O 3 @TiO 2 ) and (ii) concentration (0–200 mg/L) of additives. During the screening of additive type, approximately 14 wt% nano-sized (6 nm) hematite (Fe 2 O 3 ) doped Al 2 O 3 showed the highest improvement for biohydrogen production yield among all additives. Batch experiments conducted through dark fermentation demonstrated that 50 mg/L Fe 2 O 3 @Al 2 O 3 addition caused an acceleration in biohydrogen production by 34% and an increment in yield by 15%, despite even low concentrations Al 2 O 3 addition inhibited the process. • Hematite doped metal oxides synthesized using hydrothermal methods. • Biohydrogen production activity of Fe 2 O 3 @Al 2 O 3 , Fe 2 O 3 @ZrO 2 , Fe 2 O 3 @TiO 2 were tested. • Buffer solution and concentration selection carried out. • Fe 2 O 3 @Al 2 O 3 showed best enhancement with 15% increment in yield. • 50 mg/L Fe 2 O 3 @Al 2 O 3 accelerated biohydrogen production 34%.

Calorimetric Evaluation of Thermal Stability of Organic Liquid Hydrogen Storage Materials and Metal Oxide Additives

The effects of two different metal oxide catalysts, SnO and Li2O, on the dehydrogenation temperature of Carbazole and N-Ethylcarbazole (NE), respectively, were investigated by the Thermogravimetric analyzer and Differential Scanning Calorimetry. Thermogravimetric experiments were performed with 10wt% SnO and Li2O added to Carbazole and N-Ethylcarbazole, respectively, and compared to pure Carbazole and N-Ethylcarbazole. The results showed that the dehydrogenation temperature of N-Ethylcarbazole was lower than that of Carbazole, and the dehydrogenation temperature of N-Ethylcarbazole +SnO was the lowest, and SnO is an ideal dehydrogenation catalyst for N-Ethylcarbazole. Experiments using Differential Scanning Calorimetry and a Thermogravimetric analyzer showed that with the addition of catalyst, the activation energy of the mixture was more significant and stable, and the thermal hazard was reduced, whereas the relative dehydrogenation temperature was increased. This study provides important information for improving the design of dehydrogenation catalysts for organic liquid hydrogen storage processes.

Structure, optical properties, and ionizing radiation shielding performance using Monte Carlo simulation for lead-free BTO perovskite ceramics doped with ZnO, SiO2, and WO3 oxides

This study reports the influence of different oxides doping on the structure, optical characteristics, and radiation protecting performances of perovskite BaTiO3 (BT used thereafter) ceramic synthesized by solid-state reaction process. The crystal structure and phase identification are examined through X-ray diffraction technique (XRD) and Rietveld refinement analyses that confirm a monophasic tetragonal structure with a P4mm space group in BT ceramic. The tetragonality is maintained with ZnO doping, however, for ceramics doped with WO3 and SiO2, a cubic structure is detected with the presence of some impurities. The variation in the structural parameters is indicative of the distortion in the unit cell under the influence of different oxides doping. The optical properties reveal a variation in optical bandgap under the effect doping. The values of Eg follow the order of BT: Zn < BT < BT: W < BT: Si. BT doped with SiO2 exhibits a wider bandgap energy (3.41 eV) compared to all prepared ceramics. The radiation shielding studies were examined using Monte Carlo simulation. The linear attenuation coefficient (μ) values for BaTiO3 are 1.238, 0.453, and 0.297 cm−1 for photons with energies 0.244, 0.662, and 1.332 MeV, respectively, and these values were increased gradually with the addition of ZnO or WO3 metal oxides. In contrast, the addition of SiO2 compounds to the basic composition BT causes a reduction in both the density and shielding capacity of the fabricated BT. The half-value thickness (Δ0.5) was evaluated and the results demonstrated that the Δ0.5 increases between 0.560 and 2.399 cm (for BT ceramics), 0.555–2.370 cm (for BT: Zn), 0.528–2.293 cm (BT: W), and 0.609–2.619 cm (for BT: Si ceramics) when the γ-ray energy raised between 0.244 and 1.408 MeV, respectively. Also, the addition of ZnO and WO3 slightly enhance the Δ0.5 values by a factor of 1.142% and 4.532%. On the other hand, the addition of the SiO2 compound to BaTiO3 increases the Δ0.5 value by a factor of 9.16%.

Active catalytic species generated in situ in zirconia incorporated hydrogen storage material magnesium hydride

This study explores how zirconia additive interacts with MgH 2 to improve its hydrogen storage performance. Initially it is confirmed that the zirconia added MgH 2 powder releases hydrogen at a temperature of about 50 °C below that of the additive free MgH 2 . Subsequent tests by X ray diffraction (XRD) and infrared (IR) spectroscopy techniques reveal that the ZrO 2 mixed MgH 2 powder contains ZrH x (2 <x> 1.5) and MgO secondary phases. This observation is supported by the negative Gibbs free energy values obtained for the formation of ZrH 2 /MgO from ZrO 2 /MgH 2 powder samples. An X ray photoelectron spectroscopy (XPS) study reveals that apart from Zr 4+ cations, Zr 2+ and zero valent Zr exist in the powder. Atomic force microscopy (AFM) study reveals that the average grain size is 20 nm and the elemental line scan profiles further proves the existence of oxygen deficient Zr bearing phase(s). This study strengthens the belief that functional metal oxide additives in fact chemically interact with MgH 2 to make active in-situ catalysts in the MgH 2 system.

An overview on metal Oxide-based materials for iodine capture and storage

• Sources and reactions of various iodine species are summarized. • Metal oxide-based adsorbents’ potential abilities for iodine capture are discussed. • Metal oxides can form stable oxyiodide forms for long-term radioidine storage. • Silver and Bismuth oxides show better performance for iodine capture and storage. • Metalloid oxides are used as low-sintering temperature additives to limit iodine loss during storage. Long-lived 129 I, short-lived 131 I, and organic iodides released from nuclear plants are volatile and harmful to the ecosystem. For operational safety, and sustainable development of nuclear industries, effective means of trapping various iodine radioisotopes are of great concern. Wet scrubbing methods are often combined with adsorbents to entrap radioiodine species effectively, and thus the search for materials with high performance is still needed. Metal oxides are believed to be potential candidates for real applications. In this review, we documented the metal oxide-based materials for volatile radioactive iodine capture, with limitations on operating conditions, adsorption capacities, and long-term immobilization. Advantages, shortcomings of various metal oxides toward iodine capture, and metal oxide additives for a low-sintering temperature of iodide waste forms have been elucidated for helping in the long-term future development of efficient materials for iodine capture and storage.

Enhanced photooxidative desulphurization of dibenzothiophene over fibrous silica tantalum: Influence of metal-disturbance electronic band structure

Fibrous silica tantalum (FSTa) and a series of metal oxides (silver oxide (AgO), copper oxide (CuO) and zinc oxide (ZnO)) supported on FSTa were prepared by hydrothermal and electrochemical method, respectively. X-ray diffraction, nitrogen adsorption-desorption analyses, Fourier-transform infrared, ultraviolet–visible diffuse reflectance spectroscopy, and photoluminescence were used to characterize the catalysts. The catalyst activity towards on photocatalytic oxidative desulfurization (PODS) of 100 mg L−1 dibenzothiophene (DBT) was ranked in the following order: FSTa (3.03 × 10−3 mM min−1) > Zn/FSTa (2.65 × 10−3 mM min−1) > Cu/FSTa (2.33 × 10−3 mM min−1) > Ag/FSTa (1.46 × 10−3 mM min−1) under visible light irradiation for 150 min. This result demonstrated that the addition of metal oxides lowered the efficiency of PODS of DBT, most probably due to the unfit energy level of the photocatalyst towards redox potentials of superoxide anion radical (⋅O2−) and hydroxyl radical (⋅OH). Nevertheless, among the metal oxides loaded FSTa, Zn/FSTa showed a higher desulfurization rate, which likely due to its higher valence band energy (EVB = 3.12 eV) than the redox potential of the H2O/⋅OH (+2.4 eV vs. NHE), which allowed the production of ·OH for oxidation of DBT into dibenzothiophene sulfone (DBTO2). In parallel, the hole at the VB of ZnO can also directly oxidize DBT to DBTO2, as confirmed by the scavenger experiment. A kinetics study using Langmuir–Hinshelwood model illustrated that the photodegradation over Zn/FSTa followed the pseudo-first-order, and adsorption was the rate-limiting step. These findings are believed to aid in the rational design of high-performance photocatalysts for various photocatalytic applications, especially the removal of sulphur-containing compounds from fuel oils.

Slow pyrolysis of waste navel orange peels with metal oxide catalysts to produce high-grade bio-oil

Abstract Renewable biomass resources have become increasingly attractive in recent years. In this study, the pyrolysis of waste navel orange peels was carried out with different metal oxides (Cu2O, CaO, V2O5, Fe2O3, and ZnO) in a tube furnace to obtain high-quality bio-oil, from which high-value chemicals such as 3-furaldehyde could be well recovered to enhance the economic value of waste navel orange peels. The effects of different metal oxides on bio-oil were analyzed by GC/MS. The results showed that Cu2O and Fe2O3, as catalysts for slow pyrolysis, promoted the production of 3-furaldehyde compounds at a scale of approximately 5.69 and 4.82 times higher than that of pyrolysis without the addition of metal oxides, respectively. High-value chemicals such as 3-furaldehyde obtained from bio-oil can enhance the economic value of waste navel orange peels for full recovery and reuse.

Optimization of nickel-iron bimetallic oxides for coproduction of hydrogen and syngas in chemical looping reforming with water splitting process

Chemical looping reforming with water splitting (CLRWS) to coproduce the syngas and high purity hydrogen was investigated using Ni–Fe bimetallic oxygen carriers (OCs). The oxygen carrier with 20 wt% of NiO (termed as Ni20Fe80) was more suitable for CLRWS at 900 °C with a mass ratio of steam to bio-oil (S/B) of 1.2. Under the condition, the syngas exhibited a yield of 1.79 Nm3/kg with a H2/CO ratio of 2.01 in fuel reactor (FR), meanwhile, the hydrogen presented a yield of 0.70 Nm3/kg with a purity of 96.04% in steam reactor (SR). However, the stability of Ni20Fe80 gradually decreased during the cyclic test. Three metal oxide additives, including CeO2, Al2O3 and TiO2, with a mass fraction of 25 wt%, were used to modify the Ni20Fe80. The corresponding OCs were abbreviated as Ni15Fe60Ce25, Ni15Fe60Al25 and Ni15Fe60Ti25. The Ni15Fe60Ce25 exhibited the best performance during the cyclic test. After 5 cycles, the syngas yield, hydrogen yield and purity were 2.01 Nm3/kg, 0.75 Nm3/kg and 96.26%, respectively. The Ni15Fe60Al25 has good potential for syngas production, but not suitable for hydrogen production in SR. It was attributed to that the formation of iron-aluminum spinel regulated the lattice oxygen reactivity to favor the syngas production, as well inhibited the reduction of Fe species, which resulted in a low hydrogen yield in SR.

Investigation of a ternary blend of diesel/ethanol/n-butanol with binary nano additives on combustion and emission: A modeling and optimization approach with artificial neural networks

The increase in global energy consumption and concerns about fossil fuels depletion are pushing the demand for renewable and clean energy sources. Alcohols are a promising candidate for internal combustion engines as alternative fuels. This study aims to reveal the effect of a ternary blend, which is denominated D80E10nB10, consisting of diesel (80%), ethanol (10%), and n-butanol (10%) on combustion and emission characteristics. The addition of both metal oxide (TiO2) and nonmetallic nanoparticle (MWCNT) was also investigated with the above-mentioned ternary blend fuels, which are denominated “m-”. The compression ignition engine was run under dual fuel mode with feeding H2 in the range of 5 and 15 g/h, which were labeled D80E10nB10H5 and 15. The results revealed that the maximum pressure increased by 3.63 and 3.94% by adding 5 and 15 g/h H2 respectively into ternary blend fuel under the full load. The highest BTE was obtained from modified diesel fuel which was 23.24% higher than diesel. Furthermore, 60 Artificial Neural Network (ANN) models were built to optimize test conditions. The optimal conditions for ternary blend fuel were found to be 4 g/h H2 feeding rate while 5.5 g/h H2 addition with modified ternary blend fuel would be the optimal.

Effect of transition metal oxides addition on the color tone of Bi&lt;sub&gt;4&lt;/sub&gt;V&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;11&lt;/sub&gt;-based red pigments

Bi4V2O11 (BiVO) is an Aurivillius-type layered compound that exhibits a red color, and has been attracting attention for its non-toxicity. In this study, we have synthesized a variety of metal oxide-doped Bi4V2O11, and aimed to evaluate the effect of the doped metal element on the color tone of the pigments. Bi2O3 and V2O5 were weighed to 2:1 in mole fraction and mixed in a dry-ball mill with zirconia media for 10 min. Next, transition metal oxides (MnO2, α-Fe2O3, CoO, NiO, CuO, TiO2, ZrO2, and HfO2) were added to the Bi2O3–V2O5 mixture, and they were mixed, and calcined at 800 °C in the air for 10 h. The obtained powders were pulverized to obtain sample pigments, BiVO and BiXVO (X = Mn, Fe, Co, Ni, Cu, Ti, Zr, and Hf). The BiVO pigment had a brownish-red color. The BiFeVO, BiNiVO, BiTiVO, BiZrVO, and BiHfVO pigments demonstrated orangish-red colors. The BiCuVO pigment displayed a dark and dull yellow, and the BiMnVO and BiCoVO pigments showed black achromatic colors, which were verified by UV–Vis spectroscopy.