NiO Content Research Articles

Design and performance exploration of Pb-free low-cost all-inorganic perovskite-inspired CuAgBi2I8 solar cells: theoretical approach

Abstract Organic–inorganic halide perovskites have demonstrated great potential for photovoltaic applications owing to their unprecedented optoelectronic properties and low manufacturing costs. However, the commercialization of this technology is hindered by its thermal instability and inherent toxicity. In this study, SCAPS-1D simulation software was used to study the performance of solar cell based on CuAgBi2I8, which is a novel inorganic non-toxic lead-free perovskite-inspired material. Different electron transport layers (TiO2, In2S3, ZnO, Zn0.75Mg0.25O,SnO2 and SrTiO3) and hole transport layers (CuI, PEDOT:PSS, CuSCN and Cu2O) were studied, our research indicated that SnO2 and NiO formed the optimal combination. Further analysis revealed that the optimal absorption layer thickness was 900 nm, the absorption layer doping concentration should be less than 1 × 1013 cm−3 and the defect density should be less than 1 × 1014 cm−3. The optimal thickness of SnO2 and NiO was 30 nm, the optimal doping concentration of SnO2 and NiO was 1 × 1020 cm−3, the defect density of absorber layer/SnO2 and absorber layer/NiO interfaces should be less than 1 × 1012 cm−3, C was the optimal back electrode material. Consequently, the optimal device configuration was identified as FTO/SnO2/CuAgBi2I8/NiO/C, the efficiency was improved from original 2.76% to 19.10% after above optimization. These results indicate that solar cell with CuAgBi2I8 as the absorber layer is a potential alternative to organic–inorganic lead halide perovskite solar cells.

The Geology, Geochemistry, and Mineralogy of the Moa Bay Ni Laterite Mining District, Cuba

Abstract The Moa Bay lateritic Ni-Co mining district (eastern Cuba) has total mineral resources of 198.54 million metric tonnes (Mt) at 1.07% Ni and 0.12% Co. Laterite profiles from this district are characterized by their oxide-dominated ore zones. Laterite profiles from the Yagrumaje Norte, Punta Gorda, and Yamanigüey deposits contain average Ni and Co concentrations in the oxide zone of 0.88 and 0.12%. Goethite is the most abundant mineral in the oxide zone and the most important Ni-Co-Sc–bearing mineral, with median NiO, CoO, and Sc contents of 0.78 wt %, 0.07 wt %, and 58 ppm, respectively, and up to 2.77 wt %, 0.26 wt %, and 117 ppm. Maghemite is also widely present (avg of 5% and up to 19% modal proportion) and represents an important but largely ignored Ni- and Co-bearing ore phase, with median NiO and CoO concentrations of 2.11 and 0.25 wt %, respectively, and maximum values of 13.9 and 1.84 wt % each. Nickel and Co substitute for ferric iron in the structure of maghemite. Manganese oxyhydroxides (lithiophorite and lithiophorite-asbolane intermediate), which are also significant Ni-Co–bearing phases, have median NiO and CoO contents of 10.6 and 6.41 wt %, respectively. Some Mn oxyhydroxides, which formed after replacing goethite, also contain significant amounts of Sc (up to 94 ppm). Although most deposits in the Moa Bay lateritic district are classified as oxide type, Yamanigüey (avg Ni grade of 1.98%) is characterized by well-developed saprolite horizons, with secondary serpentine (serpentine II) and garnierite being the main Ni-bearing phases.

Ni2+ concentration-dependent and temperature-dependent NIR photoluminescence properties in novel transparent glass-ceramics containing cubic CaTa2O6: Ni2+ nanocrystals

Novel transparent glass-ceramics (TGCs) containing cubic α-CaTa2O6: Ni2+ nanocrystals and their Ni2+ concentration-dependent and temperature-dependent spectroscopic properties were reported. They were obtained from precursor glasses (PGs) with a subsequent heat treatment, in which the PGs of 31CaO-31Ta2O5-38Al2O3-xNiO (x = 0.02–1.5 in mol%) were prepared by the aerodynamic levitation technique. A broadband near-infrared (NIR) emission with a full width at half maximum (FWHM) of ∼250 nm was observed at ∼1220 nm under excitation at 980 nm, attributing to the spin-allowed transition of 3T2g (3F) → 3A2g (3F) of Ni2+ in octahedral Ta5+ sites in α-CaTa2O6. With the increasing of NiO content, the emission intensity increases at first reaching a maximum at x = 0.3 mol%, and then declines. A red-shifting emission from 1189 to 1258 nm is observed with a broadening FWHM from 218 to 292 nm and a significantly reducing average lifetime from 594.4 to 56.0 μs. When the temperature increased from 298 to 473 K, the emission shows an apparent thermal quenching with a blue shift of 15 nm, where the intensity remained 51 % at 373 K of that at 298 K. Furthermore, it supposes that there are two types of Ni2+ active centers according to the deconvolution of the photoluminescence (PL) spectra, double-exponential fitting of the decay curves and temperature-dependent PL spectra. One shows a stronger concentration quenching, while the other exhibits a more serious thermal quenching. The possible thermal quenching mechanism was also discussed.

Nickel oxide nanoparticles embedded in polymer-matrix nanocomposite prepared by nanosecond laser ablation method for optoelectronic applications

The polymeric PVA structure embedded with nickel oxide nanoparticles (NiO NPs) was synthesized using nanosecond pulsed laser ablation in liquid media technique for optoelectronic applications. A comprehensive investigation was conducted on the optical and electrical characteristics of the fabricated films to demonstrate the proficiency of the proposed nanocomposite film in that particular domain. Different weights of NiO nanoparticles were generated by embedding them in PVA film using different ablation durations. It was shown that as the concentration of NiO embedded in PVA increased in correlation with the ablation period, the absorption peak changed to a longer wavelength, and the absorption edge of PVA changed towards lower photon energy with a reduction in the band gap density. Followed by the increase in disorder degree through the addition of NiO NPs, while an average value of the dispersion energy is identical, and the nonlinear parameters (χ(3) and n2) increase. Also, the results emphsies that the dielectric characteristics were affected as the concentration of NiO NPs increased due to the rise in the density of states, which resulted in the generation of polarization. Due to the creation of the charge transfer complex, the optical conductivity of the produced nanocomposites rises as the concentration of NiO NPs increases. Therefore, the optical and electrical characteristics of PVA are significantly affected by the incorporation of NiO nanocomposites.

Deformation and melt–rock interaction in the upper mantle: Insights from the layered structure of the Horoman peridotite, Japan

To obtain a better understanding of melt–rock interactions in the upper mantle, microstructural and petrological analyses were conducted on deformed mantle peridotites from the Horoman peridotite complex, Hokkaido, Japan. The Horoman peridotite complex is lithologically heterogeneous and contains various kinds of ultramafic and mafic rocks. We studied an outcrop of 3 × 70 m in size that contains layered spinel harzburgite, plagioclase lherzolite, and mafic rocks. The results indicate that reactive melts migrated preferentially along the foliation in the already deformed peridotite, and that these melt-rich zones became especially prone to further deformation. This inference is supported by (1) the parallelism of the boundaries of rock layers and foliation in the deformed peridotite, and the shape and crystallographic preferred orientations (SPOs and CPOs) of olivine in the peridotites; (2) the diffusive trends of magnesium and modal compositions of pargasite grains near the boundaries between peridotite and mafic layers; (3) variations in the NiO content of olivine crystals; (4) variations in olivine CPOs with orthorhombic (010)[100] slip system patterns and weak fiber-[010] patterns; and (5) the strong pargasite SPOs, the cuspate shapes of the pargasites, and the absence of intercrystallite deformation. The results, combined with previously reported P–T conditions for the Horoman peridotite complex, indicate that the deformed peridotites and mafic rocks with a layered structure represent temperatures of 1050–1150 °C and pressures of 0.7–1.5 GPa. Our results suggest that a decrease in pressure led to the transition from a melt-free to a melt-bearing system with a consequent change in the deformation mechanism, from dislocation creep in the melt-free system to diffusion creep in the melt-bearing system, with strain localization in the fine-grained melt-rich layers. The change in deformation mechanism is likely to have occurred in the uppermost mantle beneath a mid-ocean ridge, where strong rheological contrasts are controlled by spatial variations in the melt fraction.

Stability performance of an Algerian Ni/purified diatomite catalyst in the dry reforming methane reaction: characterization and properties

AbstractThis work aims to characterize and study the properties of an Algerian diatomaceous earth (Sig-Mascara) as a catalyst carrier. A commercial product of diatomite was characterized by granulometric analysis, X-ray fluorescence, X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis/differential scanning calorimetry and scanning electron microscopy/energy-dispersive X-ray spectroscopy methods. To purify the diatomite and remove the impurities (iron oxides, clay minerals, quartz and organic matters), the <63 μm fraction of the diatomite was separated out. The 15Ni/Ds-700 catalyst has lower SiO2, Al2O3 and CaO contents compared with the original diatomite. The NiO content of the catalyst is 15 wt.%, indicating successful impregnation. According to the nitrogen sorption–desorption results, the specific surface area of the purified diatomite particles (<63 μm) increased from 26.47 to 46.33 m2 g–1 compared to crude diatomite. The 15Ni/Ds-700 catalyst was applied in the dry reforming of methane to obtain synthesis gas (CO and H2). The results showed that the catalyst was relatively stable during catalytic measurements for 6 h, although the conversion rate value was low (12%).

Selective production of phenol from the end-of-life wind turbine blade through catalytic pyrolysis

This study employed catalytic pyrolysis to enhance the selectivity and yield of phenol in the pyrolysis oil derived from the end-of-life wind turbine blade (WTB). It was confirmed that the NiO(10)/Al2O3 catalyst exhibited the best activity, reaching a phenol selectivity of 28.57 % at 500 °C with a heating rate of 10 °C/min. Furthermore, a competitive phenomenon between the catalytic formation of phenol and that of gaseous products was observed. Characterization results indicated that at lower loading content of NiO on the Al2O3 carrier, NiAl2O4 crystals tended to form preferentially, which reduced catalyst activity by covering surface strong acid sites. With increasing the loading content of NiO, saturation of NiAl2O4 formation occurred, and free NiO crystals became dominant. This resulted in the creation of abundant Lewis acid sites, enhancing the catalytic formation of phenol. Whilst, excessive accumulation of free NiO crystals increased strong acid sites and significantly generated lattice oxygen, promoting the cracking of pyrolysis oil to gaseous products, which was detrimental to phenol enrichment but facilitated the production of H2-rich syngas. The conclusions offered valuable insights for upgrading pyrolysis products derived from epoxy resin polymers during the recovery of end-of-life WTB.

Corrosion behavior of laser directed energy deposited SS316L/Inconel718 functionally graded materials

Functionally graded material (FGM) can exhibit a variety of excellent properties by controlling layer-by-layer gradients in composition and microstructure. In this paper, SS316L/Inconel718 FGM was fabricated by laser directed energy deposition (LDED) to investigate the microstructures and corrosion behaviors at the transitional interfaces. The results indicate that the microstructures in gradient regions along the build direction include cellular crystals, dendritic structures, columnar crystals, and equiaxed crystals. With increasing mass fraction of IN718, the precipitates within the FGM matrix transition from metal oxides to Laves phases and MC phases, accompanied by elemental segregation of Nb and Mo at the grain boundaries. The enhanced corrosion resistance is attributed to the increased pitting corrosion resistance elements within the FGM matrix. Additionally, the high content of Cr2O3 and NiO in the passive film enhance the corrosion resistance. The SKP and LEIS test results indicate that the LDED-manufactured SS316L/IN718 FGM exhibits no apparent galvanic coupling corrosion and maintains excellent corrosion resistance transition. This investigation offers a reference for the study of corrosion-resistant composite materials.

Improvement of energy storage properties of NN-based ceramics by high-entropy strategy and A-site cation vacancies

High-entropy dielectric capacitors have recently drawn increasing attention in the field of energy storage. In this study, NiO has been incorporated into [(Na0.7Bi0.1)0.8Sm0.02Ca0.02Sr0.02Ba0.02]Nb0.8Sb0.1Ta0.1O3-based ceramics. We applied the concept of high-entropy design to introduce cation vacancies at the A-site, enhancing conformational entropy. This approach led to the successful preparation of a novel type of energy-storage ceramics with an ABO3 perovskite structure, denoted as (1-x)NBSCSBNST-xNiO (x = 0, 0.02, 0.04, & 0.06). We conducted a systematic study of the microstructural, dielectric, and ferroelectric characteristics, along with an exploration of the influence of the high-entropy strategy on their performance. The ΔSconfig increases with NiO doping, and the Eb of the NBSCSBNST-0.02Ni sample exhibits a significant increase to 730 kV/cm from 550 kV/cm of NBSCSBNSTN. This enhancement is accompanied by a recoverable energy density (Wrec) of 4.43 J/cm3 and an efficiency (η) of 75.9 %. As the content of NiO increases from x = 0 to x = 0.06, the phase transition diffusion behavior strengthens. Additionally, the permittivity (εr) spectrum becomes more uniform, and the activation energy of the prepared ceramic samples increases from 1.03 eV to 1.76 eV. This effect suppresses the emergence of localized electric branching, eventually improving the breakdown strength of NBSCSBNST-xNi ceramic materials. The obtained results indicate that the concept of high-entropy design to introduce cation vacancies at the A-site is an efficient approach to improve the energy storage characteristics of lead-free dielectric capacitors.

Surfactant assisted wet chemical synthesis of Cu doped NiO@CNF nanocomposites and their photocatalytic behaviour in degrading brilliant green dye under UV light irradiation

This manuscript details the synthesis of pure NiO and various concentrations of Cu-doped NiO using a simple co-precipitation method, with particular amount of carbon nanoflake (CNF) loading. The prepared materials were initially characterized using X-ray diffraction, scanning electron microscopy with EDAX, transmission electron microscopy, energy dispersive X-ray. Further, UV-diffusion reflectance spectra studies were conducted to explore the optical properties of the prepared nanocomposites. XPS was utilized to explore the surface chemical states and interactions. The XRD pattern analysis revealed that both pure NiO and Cu-doped NiO nanoparticles (NPs) exhibited a face-centered cubic structure. Subsequently, the photocatalytic efficiency of the synthesized samples was evaluated for the degradation of the organic pollutant like brilliant green (BG) under UV light irradiation. Significantly, 30 mol % Cu-doped NiO@CNF nanocomposite demonstrated an enhanced photocatalytic efficiency (97 %) in degrading BG dye when compared to doped oxide materials under UV light. Moreover, the stability of the catalyst was outstanding, and it was effectively reused for five consecutive cycles.

An Amperometric Type NO2 Sensor Utilizing La0.7Sr0.3MnO3−δ -NiO Composite Sensing Electrode

NO2 is an important pollutant of automobile engines and industrial fuels, making it important to quantitatively monitor and control. An amperometric-type NO2 gas sensor was fabricated using yttria-stabilized zirconia (YSZ) electrolyte with a bi-layered structure and La0.7Sr0.3MnO3−δ -xNiO (LSMO-xNiO, x = 0–0.75) composite sensing electrode (SE) prepared by impregnation method in combination with self-demixing. The samples were characterized using SEM, XRD, and XPS, and their performance as sensors was tested. LSMO-xNiO composite SE particles were formed by de-mixing in the process of treating the precursor at high temperatures and are uniformly dispersed in the YSZ porous backbone. With the increase of NiO content, the SE particles become significantly large. At 450 °C–600 °C, the response currents at a fixed potential have a linear relationship with the NO2 concentrations at 25–700 ppm. Combining stability and sensitivity, the voltage was fixed to −0.25 V. The introduction of NiO into the LSMO sensing electrode effectively improves the performance of the sensor. The sensor based on LSMO-0.5NiO has the highest sensitivity (0.0405 μA/ppm) at 550 °C. Simultaneously, the sensor exhibits good anti-interference ability for CH4, CO2, O2, and NO, but has obvious cross-sensitivity to H2 and NH3. In addition, the response current of the sensor change with the increase of RH.

Impact of microwave sintering and NiO additive on the densification and conductivity of BaCe0.2Zr0.7Y0.1O3-δ electrolyte for protonic ceramic fuel cell

This work investigated the influence of microwave sintering on the BaCe0.2Zr0.7Y0.1O3-δ phase, incorporating 2 mol% or 4 mol% NiO as sintering aid. X-ray diffraction analysis of perovskite phase detected a rhombohedral structure under both sintering heating rates (280 and 500 °C/min), also exhibiting the presence of a second phase deficient in Ba with Ni incorporated into the structure, replacing part of the Zr. Raman analysis indicated no distortions in the perovskite structure, independent of the rates and NiO concentrations. The efficacy of NiO addition as a sintering aid was demonstrated by high densification of the samples, exceeding 97 % relative density. Detailed analysis of structural, microstructural, and conductivity properties revealed that microwave sintering, particularly using a heating rate of 500 °C/min, yielded superior results compared to conventional sintering. The enhanced electrical response was attributed to a higher concentration of structural defects, oxygen vacancies, in the microwave-sintered samples, evidenced by the band at 630 cm−1 in the Raman spectrum. Among these, the BCZY sample with 2 mol% NiO, sintered under these conditions, stood out as the most promising, showcasing not only high density but also a uniform microstructure and appreciable electrical conductivity.

Enhanced Photodegradation of Acetaminophen Using Efficient ZnO-NiO Nanofibers

The increasing presence of pharmaceutical pollutants, such as acetaminophen, in water bodies poses a significant environmental challenge due to their persistence and potential toxicity. This study investigated the enhanced photodegradation of acetaminophen using ZnO-NiO nanofibers as superior photocatalysts. The nanofibers synthesized with varying NiO contents (designated as ZN0.5, ZN1, ZN1.5, and ZN2), were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, FTIR, Brunauer–Emmett–Teller (BET) analysis, and diffuse reflectance spectroscopy (DRS) to elucidate their structural, morphological, and optical properties. Thermogravimetric analysis (TGA) indicated that the nanofibers exhibit high thermal stability, with major weight loss attributed to the decomposition of the polymer matrix and residual organics. The BET analysis revealed that the specific surface area remains stable after increasing the NiO content up to a certain ratio. This stability correlates with the enhanced photocatalytic performance due to increased light absorption and improved charge separation. The diffuse reflectance spectra and Kubelka–Munk plots demonstrated a reduction in bandgap energy with higher NiO content, facilitating greater visible light absorption. Photocatalytic experiments under visible light irradiation, in the presence of peroxymonosulfate (PMS), showed that the ZN1.5 nanofibers achieved the highest acetaminophen degradation rate, i.e., 92%, within 3 h. Mechanistic studies, supported by radical trapping experiments, revealed that the improved photocatalytic efficiency is due to the synergistic effects of ZnO and NiO heterojunctions, which enhance charge separation and reactive oxygen species (ROS) generation. This research highlights the potential of ZnO-NiO nanofibers as effective photocatalysts for the degradation of pharmaceutical pollutants. The findings demonstrate that optimizing the composition and structure of nanofibers can significantly improve their environmental remediation capabilities, providing a promising solution for sustainable water treatment.

Why are oceanic arc basalts Ca-rich and Ni-poor? Insights from olivine-hosted melt inclusions from Kibblewhite Volcano in the Kermadec arc

Ankaramites, which are clinopyroxene-rich basalts with primitive whole-rock compositions (Mg# >65), are common in oceanic arcs and are characterized by high whole-rock CaO/Al2O3 (>1.0) ratios and olivine crystals with anomalously low nickel contents (<0.2 wt% NiO). These geochemical characteristics cannot be explained by the melting of ordinary mantle peridotite. However, their origin is critical for understanding the formation of primary magmas in oceanic arcs. Here, we investigated olivine-hosted melt inclusions (MIs) from ankaramites and magnesian andesites of the Kibblewhite Volcano in the Kermadec arc. The MIs from the ankaramites have similar major and trace element characteristics to the host rocks, indicating that the ankaramites did not result from an accumulation of mafic minerals but rather represent the primary magma in the Kibblewhite Volcano. The MIs from the magnesian andesites were hosted in forsteritic olivine xenocrysts with a wide range of NiO contents (Fo90–92; 0.13–0.39 wt% NiO) and have similar major element compositions to the ankaramites but exhibit a wide range of CaO/Al2O3 (0.85–1.54). The trace element characteristics of the MIs from the magnesian andesites do not match those of the host rocks, indicating that they are not primary melts of the magnesian andesites but primitive basaltic melts generated before the magnesian andesites formed.Interestingly, the CaO/Al2O3 ratio of MIs from the magnesian andesites was negatively correlated with the NiO content of their host olivines. This correlation suggests that the composition of the primary basaltic magmas of the Kibblewhite Volcano changed continuously from peridotite-derived to ankaramitic. This correlation could not be explained by grain-scale process, crustal anatexis, or contribution of slab-derived carbonate-rich fluids. Instead, we propose that this correlation can be explained by the interaction of the ascending primary basaltic melts with the lithospheric mantle. During melt-mantle interaction, the assimilation of clinopyroxene and fractionation of olivine and orthopyroxene caused the CaO/Al2O3 ratio to increase in the melt and the Ni content to decrease. Furthermore, because the magnesian andesites have low CaO/Al2O3 ratios and could be derived from a clinopyroxene-poor mantle lithology, the interaction between the melt and mantle may also be closely related to the origin of the magnesian andesites at Kibblewhite Volcano. This interpretation provides a new perspective on the origin of the oceanic arc ankaramites and why primary andesitic and basaltic magmas coexist in the Kibblewhite Volcano.

Structure and magnetic properties of (Ni,Fe)Fe2O4 derived from nickel slag via molten oxidation

The large amount of nickel-iron resources in nickel slag urgently needs to be recycled. In this study, (Ni,Fe)Fe2O4 was prepared by phase reconstruction of the nickel slag by molten oxidation method. The thermodynamic conditions and feasibility of the formation of (Ni,Fe)Fe2O4 during molten oxidation were analyzed by combining thermodynamic calculation and experimental research. The influence of the different NiO contents on the cation distribution and magnetic properties of (Ni,Fe)Fe2O4 was analyzed. Additionally, the mechanism governing Ni incorporation within the (Ni,Fe)Fe2O4 lattice was elucidated. The results show that the sulfide phase and silicate phase of Fe and Ni in the nickel slag were finally transformed into (Ni,Fe)Fe2O4 phase, which was preferentially precipitated during the cooling process. (Ni,Fe)Fe2O4 is formed by the replacement of Fe2+ at the octahedral site in Fe3O4 by Ni2+. As more Fe2+ is replaced by Ni2+, (Ni,Fe)Fe2O4 solid solution exhibits high permeability and low coercivity. The recoveries of Fe and Ni are up to 77.89 % and 80.8 % via the molten oxidation process, respectively. This work not only provided a theoretical foundation for the preparation of (Ni,Fe)Fe2O4 by molten oxidation but also promoted the recovery of valuable metal resources in nickel slag.

Physical and Thermoelectric Properties of Ternary Semiconducting NiO–V2O5–TeO2 Glasses

Five samples of ternary semiconducting 65V2O5 –xNiO–(35–x) TeO2 glasses, with 5 ≤ x ≤ 25 (x in mol%), were prepared using a press-quenching method from a glass melt. The thermoelectric Power (TEP), density, oxygen molar volume (Vm) and x-ray diffraction (XRD) were analyzed. TEP measurements were conducted within the temperature range of 300 – 506 K for the mentioned glass compositions. Information on the creation of polarons and the disorder energy arising from random fields was gathered. By applying Heikes’ equation and the small polaron model theory to the TEP, the results obtained from experimental data were effectively explained. The study revealed that an increase in the NiO content in the glass led to a rise in density and a consistent decrease in molar volume. All glasses exhibited a singular phase structure.

Promoted production of aromatic hydrocarbons in biomass catalytic pyrolysis over the coupled catalysts of carbon-reduced waste lithium battery cathode materials and HZSM-5

Inexpensive catalyst sources are of great importance in the conversion of biomass to economically valuable monocyclic aromatic hydrocarbons, and transition metals (Co, Ni, Fe and Mn) rich in catalytic effects in massive waste lithium battery cathode materials are not effectively reutilized currently. For this reason, the feasibility of employing the valuable metal oxides in the carbon-reduced waste lithium battery cathode materials (waste LiFePO4 batteries, LFP, and waste LiNixCoyMn1–x–yO2 batteries, NCM) with HZSM-5 as coupled catalysts in the rape straw catalytic pyrolysis to produce aromatic hydrocarbons was explored. The carbon-reduced waste lithium battery cathode materials performed well at 5 wt% carbon loading, and the content of active components Fe2O3 (SLFPC-5) and NiO (SNCMC-5) used for the reduction of large molecular oxygenates in biomass pyrolysis gas was increased by water leaching treatment. SLFPC-5 demonstrated superior bond-cutting performance, while SNCMC-5 exhibited strong deoxygenation performance. The selectivity of monocyclic aromatic hydrocarbons (MAHs) catalyzed by SLFPC-5/HZSM-5 and SNCMC-5/HZSM-5 was as high as 63.69 % and 79.19 %, with BTX yields of 14.58 wt% and 16.68 wt% respectively. This coupled catalytic system offers a low-cost source of catalysts for biomass catalytic pyrolysis and broadens the possibility of high-value recycling of wasted lithium batteries.

Tuning ZnO-based piezoelectric nanogenerator efficiency through n-ZnO/p-NiO bulk interfacing

ZnO based piezoelectric nanogenerators (PENG) hold immense potential for harvesting ambient vibrational mechanical energy into electrical energy, offering sustainable solutions in the field of self-powered sensors, wearable electronics, human–machine interactions etc. In this study, we have developed flexible ZnO-based PENGs by incorporating ZnO microparticles into PDMS matrix, with ZnO concentration ranging from 5 to 25 wt%. Among these, the PENG containing 15 wt% ZnO exhibited the best performance with an open-circuit output voltage/short-circuit current of ~ 42.4 V/2.4 µA. To further enhance the output performance of PENG, p-type NiO was interfaced with ZnO in a bulk hetero-junction geometry. The concentration of NiO was varied from 5 to 20 wt% with respect to ZnO and incorporated into the PDMS matrix to fabricate the PENGs. The PENG containing 10 wt% NiO exhibits the best performance with an open-circuit output voltage/short-circuit current of ~ 65 V/4.1 µA under loading conditions of 30 N and 4 Hz. The PENG exhibiting the best performance demonstrates a maximum instantaneous output power density ~ 37.9 µW/cm2 across a load resistance of 20 MΩ under loading conditions of 30 N and 4 Hz, with a power density per unit force and Hertz of about ~ 0.32 µW/cm2·N·Hz. The enhanced output performance of the PENG is attributed to the reduction in free electron concentration, which suppresses the internal screening effect of the piezopotential. To assess the practical utility of the optimized PENG, we tested the powering capability by charging various commercial capacitors and used the stored energy to illuminate 10 LEDs and to power a stopwatch displays. This work not only presents a straightforward, cost-effective, and scalable technique for enhancing the output performance of ZnO-based PENGs but also sheds light on its underlying mechanism.

Mineral chemistry and melt evolution of the mantle wedge peridotites in the Late Cretaceous Zagros Belt ophiolites (Iran): clues for the subduction initiation-induced forearc magmatism

We investigate in this paper mineral compositions and geochemical evolution of the mantle wedge peridotites preserved in the Late Cretaceous Zagros ophiolites of SW Iran. Mantle peridotites above subduction zones commonly experience distinct melting, depletion and refertilization processes as a result of the circulation of fluids derived from subducting slabs and flux melting. Our results reveal that the mantle wedge peridotites in the Zagros ophiolites are characterized mainly by residual and impregnated types. Residual peridotites resulted from early depletion and later refertilization processes, whereas impregnated peridotites developed due to episodic melt impregnations within and across the mantle. Mg#s and NiO contents, spinel Cr#, Mg#, and TiO 2 in olivines, Mg# and Al 2 O 3 contents of orthopyroxenes, and Mg#, TiO 2 and Al 2 O 3 contents in clinopyroxenes of dunites, harzburgites and lherzolites indicate the significant role of re-equilibration processes among different mineral phases and interactions with basaltic melts percolating within the host peridotites. The observed geochemical variations in the mineral chemistry of the Zagros peridotites reflect changes in magma chemistry and fluctuations in the degree of melt extraction and melt–rock interactions within the mantle peridotites. However, our data suggest that Mg–Fe distribution in the spinels of some dunites and harzburgites might also have resulted from subsolidus redistribution and exchange with surrounding olivine grains. Spinel and clinopyroxene phases in gabbroic rocks and ultramafic cumulates within the Zagros ophiolites also show significant variations in their compositions, suggesting that their magmas evolved from MORB-like to IAT, calc–alkaline and boninite suites, typical of subduction initiation-generated melts. Hence, the Zagros ophiolites present a case study of time-progressive melt evolution of the forearc oceanic lithosphere. Supplementary material: Datasets of the mineral chemistry and melt evolution of the mantle wedge peridotites in the Late Cretaceous Zagros Belt ophiolites (Iran) are available in tabular and figurative form at https://doi.org/10.6084/m9.figshare.c.7093528 . Thematic collection: This article is part of the Ophiolites, melanges and blueschists collection available at: https://www.lyellcollection.org/topic/collections/ophiolites-melanges-and-blueschists

Performance of NiO doped on alkaline sludge from waste photovoltaic industries for catalytic dry reforming of methane.

Alkali sludge (AS) is waste abundantly generated from solar photovoltaic (PV) solar cell industries. Since this potential basic material is still underutilized, a combination with NiO catalyst might greatly influence coke resentence, especially in high-temperature thermochemical reactions (Arora and Prasad, RSC Adv. 6:108,668-108688, 2016). This paper investigated alkaline sludge containing 3CaO-2SiO2 doped with well-known NiO to enhance the dry reforming of methane (DRM) reaction. The wet-impregnation method was used to prepare the xNiO/AS (x = 5-15%) catalysts. Subsequently, all catalysts were tested by using X-ray diffraction (XRD), nitrogen adsorption/desorption (BET), temperature-programmed reduction of hydrogen (H2-TPR), temperature-programmed desorption of carbon dioxide (TPD-CO2), field emission scanning electron microscopy (FESEM-EDX), and X-ray photoelectron spectroscopy (XPS). The spent catalysts were analyzed by thermogravimetric analysis (TGA/DTG), transmission electron microscopy (TEM), and temperature-programmed oxidation (TPO). The catalytic performance of xNiO/AS catalysts was investigated in a fixed bed reactor connected with gas chromatography thermal conductivity detector (GC-TCD) at a CH4:CO2 flow rate of 30 mL-1 during a 10-h reaction by following (Shamsuddin et al., Int. J. Energy Res. 45:15,463-15,480, 2021d). For optimization parameters, the effects of NiO concentration (5, 10, and 15%), reaction temperature (700, 750, 800, 850, and 900 °C), catalyst loading (0.1, 0.2, 0.3, 0.4, and 0.5 g), and gas hourly space velocity (GHSV) range from 3000, 6000, 9000, 12,000, and 15,000 h-1 were evaluated. The results showed that physical characteristics such as BET surface area and porosity do not significantly impact NiO percentages of dispersion, whereas chemical characteristics like reducibility are crucial for the catalysts' efficient catalytic activity. Due to the active sites on the catalyst surface being more accessible, increased NiO dispersion resulted in higher reactant conversion. The catalytic performance on various parameters that showed 15%NiO/AS exhibited high reactant conversion up to 98% and 40-60% product selectivity in 700 °C, 0.2 g catalyst loading, and 12,000 h-1 GHSV. According to spent catalyst analyses, the catalyst was stable even after the DRM reaction. Meanwhile, increased reducibility resulted in more and better active site formation on the catalyst. Synergetic effect of efficient NiO as active metal and medium basic sites from AS enhanced DRM catalytic activity and stability with low coke formation.