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The selective oxidation of tetrahydrofuran (THF) to gamma-butyrolactone (GBL) on spinel ZnFe2O4 nanoparticles (ZFNPs) was investigated. The catalyst was prepared with the coprecipitation method and characterized by FTIR, XRD, TEM, SEM, EDS, TGA, XPS, and BET surface area. The characterization techniques showed that a nonuniform spherical spinal oxide with an average particle size of 26 nm was formed. The oxidation reaction was carried out using hydrogen peroxide as an oxidizing agent under solvent-free conditions. GC-MS analysis revealed that the main product was GBL. 2-hydroxytetrahydrofuran (THF-2-OH), gamma-hydroxybutyric acid (GHBA), and gamma-hydroxybutaldehyde (GHBAl) were obtained as minor products. The effects of different reaction parameters, such as temperature, H2O2/THF mole ratio, catalyst dose, reaction time, and reusability, were evaluated. A 47.3% conversion of THF with an 88.2% selectivity of GBL was achieved by conducting the reaction at 80 °C for nine hours using a 1:1 mole ratio of H2O2/THF. A slight increase in the conversion degree was attained at higher temperatures; however, an over-oxidation process was observed as the temperature exceeded 80 °C. The catalyst remained effective and stable over four reuses.

Fe-doped ZnO nanoparticles (NPs) with different Fe contents (0.1–5.0 wt%) were prepared using extract of wild olive leaves growing in Saudi Arabia (region of Abha). The biosynthesized NPs were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, scanning electron microscopy, transmission electron microscopy, and photoluminescence (PL). Characterization results showed that undoped ZnO and Fe-doped ZnO powders were crystallized in the wurtzite structure with a small shift for the doped samples. Neither Fe3O4 nor another iron oxide phase was observed in the samples, which proves the incorporation of Fe into the ZnO lattice. Doping has a pronounced effect on the physical and optical properties. Indeed, the size of the crystallites, the energy of the bandgap as well as the intensity of the PL emission decreased with the Fe content. Photocatalytic tests revealed that the doped samples degraded methyl orange (MO) more efficiently than pure ZnO and pure Fe3O4. Moreover, the photocatalytic activity improved with increasing Fe content. The best photocatalyst of the series (Fe–ZnO-5) was found degrading MO by 92.1%, in 90 min in a pseudo-first order reaction.

The concept of a microgrid (MG) has been introduced to integrate the conventional generators, different renewable energy resources and energy storage systems (ESS) to meet the specific load demand. However, the intermittent nature of renewable energy resources produces a variable output, which drives an imbalance between power generation and demand in MG. The ESS is utilized to makes a balance between power generation and demand. When several renewable energy resources and ESS are available in MG as energy resources, then an energy management system (EMS) is required that can handle the stochastic nature of renewable energy resources, schedule the power of renewable energy resources and ESS for managing the power flow among MG resources and main grid while ensuing cost-effective operation. Therefore, this paper proposed an optimum EMS that aims to minimize the overall operating cost of grid-connected MG along with the short-term forecasting of PV power and load demand. The proposed EMS consists of four modules: forecasting, scheduling, data acquisition (DAQ), and human–machine interface (HMI) modules. An improved hybrid forecasting approach that combines a 3-level stationary wavelet transform (SWT) and grey wolf optimization-based least-square support vector machine (GWO-LSSVM) is proposed in the forecasting module to achieve day-ahead forecasting of PV power and load demand. In the scheduling module, the weighted salp swarm algorithm-based scheduling is applied to achieve the optimum power flow of grid-connected MG. Then, the DAQ and HMI module is used to monitor, analyze, and modified the input variables of the forecasting and scheduling module. The MATLAB/Simulink environment is then used to simulate the proposed EMS for grid-connected MG. Finally, numerical results demonstrate the efficiency of the proposed EMS for grid-connected MG with commercial load demand over the existing competitive approaches.

In this work, the isothermal decomposition of poly(methyl methacrylate) synthesized in bulk by the radical route of methyl methacrylate in the presence of azobisisobutyronitrile as the initiator was carried out and monitored for the first time with the DART-Tof-MS technique at different temperatures. Nuclear magnetic resonance (NMR) analysis revealed a predominantly atactic microstructure, and size-exclusion chromatography (SEC) analysis indicated a number average molecular weight of 3 × 105 g·mol−1 and a polydispersity index of 2.47 for this polymer. Non-isothermal decomposition of this polymer carried out with thermogravimetry analysis (TGA) showed that the weight loss process occurs in two steps. The first one starts at approximately 224 °C and the second at 320 °C. The isothermal decomposition of this polymer carried out and monitored with the DART-Tof-MS method revealed only one stage of weight loss in this process, which begins at approximately 250 °C, not far from that of the second step observed in the case of the non-isothermal process conducted with the TGA method. The results obtained with the MS part of this technique revealed that the isothermal decomposition of this polymer regenerates a significant part of methyl methacrylate monomer, which increases with temperature. This process involves radical chain reactions leading to homolytic chain scissions and leading to the formation of secondary and tertiary alkyl radicals, mainly regenerating methyl methacrylate monomer through an unzipping rearrangement. Although they are in the minority, other fragments, such as the isomers of 2-methyl carboxyl, 4-methyl, penta-2,4-diene and dimethyl carbate, are also among the products detected. At 200 °C, no trace of monomer was observed, which coincides with the first step of the weight loss observed in the TGA. These compounds are different to those reported by other researchers using TGA coupled with mass spectrometry in which methyl isobutyrate, traces of methyl pyruvate and 2,3-butanonedione were detected.

Spinel ferrites with a compatible electronic band structure are always excellent candidates for photo-catalytic environmental detoxification employing visible light and solar energy. However, the potential is not harnessed to its fullest owing to unnerving charge carrier recombination. In this work, we report the synthesis of Ni1-xZnxFe2O4 (x = 0, 0.1, 0.3, & 0.5) mixed spinel ferrites via combustion route. As prepared samples were characterized for phase identification using X-ray diffraction (XRD) and Reitveld refined pattern confirms the formation of single phased cubic structure with a nano-metric crystallite size. The homogeneous distribution of grains and particles is evidenced by shape and size morphological studies. Raman spectroscopy reveals the presence of motion of oxygen in tetrahedral and octahedral voids. The dc electrical resistivity measured using the two probe method is found to be in the range of 107 to 108 Ω-cm. The optical band gap measured for all photo-catalysts resides at 2.11–2.53 eV. The ferrite photocatalyst exhibits high visible absorption, superior charge transfer capacity, and highly suppressed recombination as suggested by electrochemical impedance spectroscopy and photoluminescence results. The change in band structure with variable Zn content was monitored by shifting of conduction and valence bands. The photo-catalyst Ni0.7Zn0.3Fe2O4 (N2) exhibited 96.8% levofloxacin (LEV) degradation in 90 min of visible light exposure. The effect of parameters such as pH, catalyst dosage, electrolytes and water matrix was analysed in detail. The photo-catalytic degradation rate was enhanced in the presence of persulfate and H2O2. Furthermore, the high magnetic character of the catalysts aids in their retrieval post utilization in catalysis. In terms of band structure analysis, role of dopants, metal redox, and scavenging studies, a suitable photo-catalytic process was proposed. Degradation intermediates discovered by liquid chromatography–mass spectrometry analysis were also recommended as a pathway of degradation. These findings open up exciting possibilities for developing novel solar active photo-catalytic systems based on spinel ferrites for efficient environmental cleanup.

Some agricultural byproducts are useful for solving wastewater pollution problems. These byproducts are of low cost and are effective and ecofriendly. The study aim was to investigate the possibility of using pomegranate peel (PP) and date pit (DP) activated carbon (PPAC and DPAC, respectively) as sorbents to remove Cd(II) and Pb(II) from aqueous solutions. Agricultural wastes of DPs and PPs were subjected to carbonization and chemical activation with H3PO4 (60%) and ZnCl2 and used as adsorbents to remove Cd(II) and Pb(II) from their aqueous solutions. The physical characterizations of PPAC and DPAC, including determination of surface area, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy, were performed. The following factors affected adsorption: solution pH, adsorbent dosage, initial metal ion concentration, and contact time. These factors were studied to identify the optimal adsorption conditions. The results showed that the maximum adsorptions of Cd(II) and Pb(II) were achieved at pH ranging from 6 to 6.5, 90 min contact time, and 0.5 g/L for PPAC and 1 g/L for DPAC dosage. Furthermore, the adsorption efficiencies for both Pb(II) and Cd(II) were higher for PPAC than for DPAC. However, the recorded Qmax values for PPAC were 68.6 and 53.8 mg/g for Pb(II) and Cd(II) and for DPAC were 34.18 and 32.90 mg/g for Pb(II) and Cd(II), respectively. The Langmuir isotherm model fit the adsorption data better than the Freundlich model. Kinetically, the adsorption reaction followed a pseudo-second-order reaction model, with qe ranging from 12.0 to 22.37 mg/g and an R2 value of 0.99.

Three-dimensional (3D) carbon from the assembly of low-dimensionally isolated segments have attracted much attention as these carbon materials not only inherit the superiorities of individual building blocks but also acquire new synergic effects. However, it remains a big issue to assemble isolated carbon segments into a 3D carbon superstructure by a facile strategy. Herein, the spheroidizing growth of hydrothermal carbon as an assembly drive and in situ formed melamine cyanurate nanosheets as structure-directing agent are combined to design and assemble B, N and O co-doped carbon flower as a promising cathode for Zn2+ hybrids supercapacitors. The flower-like carbon exhibits large nanosheets area, interlinked conductive network, nanoscale architecture and rich electroactive sites. Boron doping enhances the chemical adsorption of SO42− onto the carbon cathode surface and the reaction between oxygen dopant and Zn ions added additional capacity for Zn-ion supercapacitors. The resulting device achieves an energy density of 119.7 Wh/kg at 890 W/kg and maintains 63.5 Wh/kg even at a power density of 16.5 kW/kg.

The leading cause of global climate change and warming is greenhouse gas emissions. In developing economic activities, energy plays an important role, and human activities are responsible for climate change, carbon dioxide (CO2) emissions adverse impacts on the environment. This study investigates carbon dioxide emissions from liquid fuel consumption on CO2 emissions rather than total energy consumption. Carbon dioxide (CO2) emissions have a causal relationship of CO2 emissions from liquid fuel consumption (CO2L), industry (IND), economic growth (GDP), and trade openness (TR). The ARDL bound method incorporates the structure break and Granger causality method to measure the long-run and short-run cointegration relationship between the variables based on annual data from 1971 to 2016 Malaysia. Both the augmented Dickey-Fuller and Phillips-Perron analysis also supported exploring the study variables' stationarity. The long-run forecasts indicate that CO2L, IND, TR, and GDP are significantly related to CO2 emissions. The error correction term (ECT) value was -0.952, revealing that CO2 emissions diverged from a short-run to long-run equilibrium by 95.2% each year. Furthermore, the Granger causality test shows bidirectional causality between trade openness and CO2L. A unidirectional causality runs from the trade openness to industry at a 1% level form. The current study aims to find out the relationship between carbon dioxide emissions, economic growth, energy consumption, and trade in Malaysia to fill this scientific gap. Based on this study's results, the government needs effective policies and initiatives to identify Malaysia's ecological issues. It is also essential to determine the basic target of Malaysia's consumption of liquid fuel and its environmental mitigation policies.

Mesoporous carbonaceous materials were functionalized with iron or copper by a mechanochemical approach. The structural and textural properties of these catalysts were characterized by N2 physisorp...

The aim of this study was to investigate the potential advantage of ZnFe

This work was supported by RUSA, UGC-SAP, DST-FIST, DST-PURSE grants. The authors extend their appreciation to the Researchers supporting project number (RSP-2020/247) King Saud University, Riyadh, Saudi Arabia.

In this study, a one-step hydrothermal method was used to synthesize cadmium molybdenum oxide and revealed cationic cetyltrimethylammonium bromide surfactant effects on material preparation and energy storage characteristics. X-ray diffraction confirmed tetragonal-phase CdMoO4. Symmetric stretching modes of molybdenum oxide were confirmed from a Raman spectrum. A Fourier-transform infrared spectrum confirmed the presence of functional groups. Scanning electron microscopy images revealed a bunch of hierarchical microspheres of about 100–200 nm diameter. The specific capacitance achieved for CdMoO4, 0.1 M CTAB + CdMoO4, and 0.2 M CTAB + CdMoO4 were 200 F/g, 310 F/g, and 382 F/g, respectively, at 0.5 A/g. In addition, long-term cyclic stability for the best performing electrode (0.2 M CTAB + CdMoO4) material was investigated to explore cyclic performances of the supercapacitor. During the experiment, 86.01% capacity was retained after 5000 cycles at 5 A/g. The product activity is promising for high-efficiency supercapacitors due to the ease of production, environmentally friendly nature, and low cost of the synthesized material.

Bare and Fe doped vanadium sulfide nanorods was synthesized by employing sol-gel method. The obtained (011) plane revealed and confirmed the orthorhombic phase of vanadium sulfide (VS). Fe doped vanadium sulfide anemone like nanorods structure were demonstrated by morphological evolution employing SEM studies. FTIR studies confirmed the vibrational frequencies of the prepared samples and identify the functional groups. Raman technique is also used to observe the vibrational modes of molecules and PL revealed the prepared samples optical-electronic nature. Additionally, electrochemical studies such as cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and chronoampherometry (CA) was recorded for determination of specific capacitance, current density and stability. High doped vanadium sulfide has elevated 1372 F/g specific capacitance at 385 mA/g current density attained from CV and LSV curves at 10 mV/s and it has proven the excellent OER activity.

In this paper, mainly focused on the fabrication of ZnO nanorod based gas sensor. This sensor was aimed to detect a small amount of volatile organic compounds (VOCs) with low power, low cost and simple manufacturing method. Low power consumption is achievable by completion of metal oxide sensors. So, high sensitivity of sensor is requested to sense the target gas. It is important to find out optimal sensing structures of materials. The components of sensor were platinum electrode and heater and ZnO sensing film. SiO2 was used as thermal and electricity insulator. Herein, the ZnO nanorods was synthesized by wet chemical method, namely chemical bath deposition(CBD) and hydrothermal method (HD), were tried to check well alignment of ZnO nanorods on the sensing area. Morphology of sensing material and sensor pattern was analyzed by Scanning Electron Microscope (SEM) and EDS, phase analysis was carried out using X-ray Diffractometer (XRD). The morphology images of ZnO confirmed the formation of nanorod like structure with average diameter of 205 nm and 55 nm chemical bath deposition(CBD) and hydrothermal method (HD), respectively. Therefore, the fabricated ZnO nanorod based gas sensor device is suitable for human breath analysis. Capsule: This work investigates the fabrication of ZnO nanorods based gas sensor pattern.

Removal of hazardous organic dyes from polluted water bodies requires the introduction of strong adsorbents and photocatalysts to industrial wastewaters. Herein, photocatalytic CeO2 nanoparticles and CeO2/CuO nanocomposite were synthesized following a co-precipitation method for low cost elution of methylene blue (MB) from water. The crystallinity and surface structure of the as-prepared materials have been analyzed using characterization techniques including X-ray powder diffraction (XRPD), field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), ultra-violet visible spectroscopy (UV–Vis), and Fourier-transform infrared spectroscopy (FTIR). The average particle size of both the nano scaled samples were approximately 20–30 nm. The photocatalytic properties of CeO2/CuO were investigated under visible light against methylene blue (MB). The results showed 91% photodegradation of MB organic pollutant in 3 h as monitored by UV–Vis spectroscopy. Absorbance peaks appeared at around 670 nm corresponding to degradation of MB. Such output displayed the effectiveness of Ce nanocomposites for environmental benefits. Hence, CeO2/CuO nanocomposite could be useful for treatment of industrial wastewaters by removing hazardous MB dye.

Hybrid composites have great potential for specific strength and specific stiffness, effective in aerospace industries, submarines, and light-weight automotives. The mechanical strength and adhesiveness of hybrid laminates can be enhanced by effective use of matrix materials in different ratios of epoxy resin and epoxy hardener. Gentle use of resin and hardener in the fabrication of hybrid composites can alter tensile modulus, the bonding strength between matrix and fabric. Spectacular progress has been achieved by the selection of appropriate amounts of resin and hardener in the hybridization of composite laminate. Hybridization was made by Kevlar inorganic/organic fabrics and glass fabrics stacked with epoxy matrix material. To achieve the combination of mechanical properties and bonding strength, transparent epoxy resin and hardener of commercial grades mixed in various ratios are incorporated as matrix material to fabricate laminate. Three different sheets, named A (3:2), B (4:1), and C (2:3), were embedded by the hand layup method to prepare a hybrid composite. Experimental tests, according to ASTM 3039, were performed to determine the tensile mechanical properties. Peel tests, according to ASTM 6862-11, were performed to investigate the interlaminar strength between Kevlar and glass layers. Shore A and Shore C hardness durometers were used to find out the hardness of the specimens at different spots using the ASTM D-2240 standard. Finally, physical testing, such as density and then water absorption, was carried out using the ASTM D-570 standard to check the swelling ratio of the different specimens. The results obtained highlight that the specimen of the glass/Kevlar hybrid embedded in the ratio 3:2 in lamination has the best mechanical properties (tensile strength and hardness) and the lowest swelling ratio, while the material system in the ratio 4:1 shows the best interlaminar properties and adhesion capabilities.

The ubiquitous problem of pesticide in aquatic environment are receiving worldwide concern as pesticide tends to accumulate in the body of the aquatic organism and sediment soil, posing health risks to the human. Many pesticide formulations had introduced due to the rapid growth in the global pesticide market result from the wide use of pesticides in agricultural and non-agricultural sectors. The occurrence of pesticides in the water body is derived by the runoff from the agricultural field and industrial wastewater. Soluble pesticides were carried away by water molecules especially during the precipitation event by percolating downward into the soil layers and eventually reach surface waters and groundwater. Consequently, it degrades water quality and reduces the supply of clean water for potable water. Long-time exposure to the low concentration of pesticides had resulted in non-carcinogenic health risks. The conventional method of pesticide treatment processes encompasses coagulation-flocculation, adsorption, filtration and sedimentation, which rely on the phase transfer of pollutants. Those methods are often incurred with a relatively high operational cost and may cause secondary pollution such as sludge formation. Advanced oxidation processes (AOPs) are recognized as clean technologies for the treatment of water containing recalcitrant and bio-refractory pollutants such as pesticides. It has been adopted as recent water purification technology because of the thermodynamic viability and broad spectrum of applicability. This work provides a comprehensive review for occurrence of pesticide in the drinking water and its possible treatment.

The water resources contamination in an alarming concern for sustainable environment. This has led to development of new technologies and materials for waste water detoxification. In the present study, we have fabricated novel trimetallic based mixed oxides decorated reduced graphene oxide (rGO) composite using facile microwave method and utilized it as an adsorbent for the removal of congo red dye from aqueous solution. The final composite showed highly agglomerated metal oxides present on the rGO surface. The high surface area and activity of the synthesized adsorbent resulted in its high adsorption capacity of 333.32 mg/g for congo red. The Langmuir model better explained the isotherm data indicating the monolayer adsorption of congo red molecules onto Ag

This study focusses on the synthesis of silver nanoparticles (Ag-nPs) by citrus fruit (Citrus paradisi) peel extract as reductant while using AgNO3 salt as source of silver ions. Successful preparation of biogenic CAg-nPs catalyst was confirmed by turning the colorless reaction mixture to light brown. The appearance of surface Plasmon resonance (SPR) band in UV-Vis spectra further assured the successful fabrication of nPs. Different techniques such as FTIR, TGA and DLS were adopted to characterize the CAg-nPs. CAg-nPs particles were found to excellent catalysts for reduction of Congo red (CR), methylene blue (MB), malachite green (MG), Rhodamine B (RhB) and 4-nitrophenol (4-NP). Reduction of CR was also performed by varying the contents of NaBH4, CR and catalyst to optimize the catalyst activity. The pseudo first order kinetic model was used to explore the value of rate constants for reduction reactions. Results also interpret that the catalytic reduction of dyes followed the Langmuir–Hinshelwood (LH) mechanism. According to the LH mechanism, the CAg-nPs role in catalysis was explained by way of electrons transfer from donor (NaBH4) to acceptor (dyes). Due to reusability and green synthesis of the CAg-nPs catalyst, it can be a promising candidate for the treatment of water sources contaminated with toxic dyes.

Polysaccharide-based hydrogels offer a great overlook for environmental applications and help in the elimination of various noxious pollutants from the water system. Novel carrageenan and itaconic acid-based superadsorbent hydrogel having appreciable swelling properties and adsorption capacity towards Methylene blue (MB), Crystal violet (CV), and Methyl Red (MR) was synthesized by suspension polymerization technique. The swelling study showed the dependency upon the temperature in which the swelling rate increased with increasing temperature with a maximum swelling rate of 417% at 318 K. For ascertaining the maximum adsorption capacity, various influential parameters such as contact time, adsorbent dose, dye concentration, and temperature were systematically studied. Maximum adsorption capacity as calculated from the Langmuir isotherm was 2439.02, 1111.11, and 666.68 mg/g for MB, CV, and MR, respectively. Thermodynamic studies revealed the spontaneous nature of the undertaken dye adsorption experiment. Overall, the present study reveals that the synthesized superadsorbent hydrogel can be used as an efficient adsorbent for the removal of dyes from an aqueous solution.

Present work include the designing of a novel porous Zn/Fe layered double hydroxide (LDH) based adsorbent using a combination of three methods, namely, co-precipitation, hydrothermal, and thermal treatment. The Zn/Fe LDH was synthesized by co-precipitation followed by hydrothermal method. The LDH was then intercalated with H2O2 and its decomposition under the thermal treatment created oxygen bubbles that pierce holes in the layered structure of the LDH by local pressure build-up. Major techniques used for assessing the morphology and surface area characteristics of the LDH and porous LDH were Scanning electron microscope (SEM) and Brunauer-Emmet-Teller (BET). The intercalation of H2O2 and its later decomposition triggered by thermal treatment lead to the introduction of pores in the LDH layers that increased the surface area from 108.863 m2/g to 168.923 m2/g. The synthesized adsorbent was utilized for the removal of an antibiotic; ciprofloxacin (CIP) from the aqueous solution. The porous Zn/Fe LDH adsorbent was featured with an admirable CIP adsorption capacity of 344.83 mg/g at pH 6.5 and temperature 298 K. The adsorption of CIP onto porous Zn/Fe LDH adsorbent followed the Freundlich isotherm model and pseudo-second-order kinetic model. The temperature increase negatively affected the adsorption rate. The adsorption mechanism of CIP onto porous Zn/Fe LDH was also projected and established, and Cπ- metal interactions, hydrogen bonding, and electrostatic interactions, were found to be the major interactive forces. The thermodynamic study revealed the exothermic and spontaneous nature of the adsorption experiments. Overall, the synthesized adsorbent is sustainable in terms of its usability and non-toxic nature.

Construction and characterization of P-N junction photodiodes have attracted the attention of researchers for past few decades as they play an important role in energy applications. The thin film samples Ag doped Bi2S3 nanowires deposited on ITO substrates with different dopant percentage using dip coating method are characterized with XRD and SEM to investigate their structure, degree of crystallinity and morphology. Ag doped Bi2S3/ITO photodiodes are fabricated, and their performance is studied and reported. The I-V characteristic graphs show an increase in photocurrent with increasing illumination time. The ideality factor of the diode is calculated to be 6.21 by J-V method under illumination of light for 30 min.

The water resources contamination in an alarming concern for sustainable environment. This has led to development of new technologies and materials for waste water detoxification. In the present study, we have fabricated novel trimetallic based mixed oxides decorated reduced graphene oxide (rGO) composite using facile microwave method and utilized it as an adsorbent for the removal of congo red dye from aqueous solution. The final composite showed highly agglomerated metal oxides present on the rGO surface. The high surface area and activity of the synthesized adsorbent resulted in its high adsorption capacity of 333.32 mg/g for congo red. The Langmuir model better explained the isotherm data indicating the monolayer adsorption of congo red molecules onto Ag2O–Al2O3–ZrO2/rGO surface. The grander adsorption ability of Ag2O–Al2O3–ZrO2/rGO towards organic dye indicate its probable utilization in the removal of other dyes also from wastewater.

Water is a crucial element for plant growth, metabolic processes, and general health. Water-deficit, typically simplified by drought stress, is the most critical photosynthetic source of stress that restricts plant growth, crop yield, and food product quality. This research highlights state of the art, possibilities for detecting the canopy temperature by integrating very-high-resolution RGB and thermal imagery from UAV. A multi-rotor drone has assembled by DJI (S900) attached with RGB thermal and cameras was used for experiments. The thermal cameras have a spectral range of 7.5– 13 μ m , a resolution of 640 × 512 pixels, thermal sensitivity of

Electric arc furnace dust (EAFD) has attracted more and more attention as a kind of metallurgical solid waste with huge production. How to reduce its harm to the environment and efficiently recover valuable metals such as zinc, lead and iron from its complex components to realize the comprehensive utilization of EAFD is the aim of various EAFD treatment processes. In this paper, the physical and chemical properties of EAFD are discussed from the micro and macro perspectives, the microstructure, chemical composition and phase composition of EAFD in various countries are summarized in detail. According to the zinc content, EAFD can be divided into three types: high-zinc, medium-zinc and low-zinc. The results show that Fe, Ni, Cr and other elements increase with the decrease of zinc content in EAFD. Not only the zinc oxide but also abundant Fe–Ni–Cr alloy of high value can be recycled from the low-zinc EAFD, which provides guidance for EAFD treatment. At the same time, the general mechanism of direct reduction and smelting reduction pyrometallurgical processes of EAFD is expounded, and the existing pyrometallurgical processes such as rotary kiln process, rotary hearth furnace process, Primus process, ESRF process and Coke-packed bed process are summarized and compared from the aspects of energy consumption, production capacity, process flow to actual application status. In addition, the properties of directly reduced iron and zinc-rich dust obtained by pyrometallurgical processes of EAFD are also discussed. Finally, a new process of treating EAFD by combining direct reduction process and smelting reduction process is proposed to overcome the defects existing in two types of pyrometallurgical processes, and the development of preparing zinc oxide micropowder and high valued Fe–Ni–Cr alloy by pyrometallurgical process of EAFD is prospected.

The performance of electrochemical energy storage (EES) devices highly rely on the in-built properties of the material. Due to the excellent properties of 2D materials, a much of research has been conducted on 2D materials. In the past decade, a novel family of 2D carbides and nitrides materials have been successfully prepared called MXene using stripping method, from layered precursors. The accessibility of solid solutions, the control of surface terminals and the latest innovation of MXene layers provide potential for the preparation of several new structures. Multifunctional chemistry of MXene allows adjustments to the performance in the field of energy storage. In addition, some distinctive EES properties have been revealed. With the advancement in EES field, it is necessary to understand the application of MXene in the EES field in time. This review primarily emphasis the synthesis, structure and energy storage application of MXene are introduced. More importantly, the theoretical and experimental electrochemical performances are compared and criticized. Finally, the future research scope and outlook of MXene in the field of energy storage systems is prospected.

Improving the energy density of symmetric flexible supercapacitors (FSSCs), while maintaining a high-power density under an environmentally safe system, is still a crucial challenge for researchers. The improvement can essentially be grasped by enlarging the voltage window through rational designing/selection of the electrode materials as well as utilizing such electrolytes that have extended stability range and non-corrosive/environmental properties. In this context, an articulate strategy is established, in the first step, fabricating the self-standing porous carbonaceous substrate (carbon nanotubes anchored at carbon fabric, denoted as CNTs-CF), in the second step, metal-oxide nano-needles (RuO2-NNs) decorated architecture was designed on the CNTs-CF substrate which served as a binder-free self-standing electrode (RuO2-NNs@CNTs-CF). The second strategy of regulating the harmless/non-toxic neutral aqueous electrolytes (NaCl, KCl & LiCl) is employed. The optimized performance of RuO2-NNs@CNTs-CF nanostructure holds a higher specific capacitance of 102.75 F g−1 in LiCl electrolyte and able to work at large voltage of 2.0 V, at the same time the retention capability of 98.6 % is achieved over 5000 cycles. Such an extended potential window is approximately twice higher as compared to the previously reported carbonaceous/metal-based supercapacitors using conventional electrolytes (acid/base in the aqueous state). In this regard, the physicochemical characteristics including mobility/diffusion and solvation of the ions are critically considered to find out their effect on the SSCs performance. Moreover, the FSSC device is also assembled using PVA/LiCl gel electrolyte; an excellent energy density of 62.94 W h kg−1 at 596.35 W kg−1 power density, is recorded with an extended voltage window of 2.35 V. The fabrication of RuO2-NNs@CNTs-CF FSSC with most safe and environmentally friendly components would unwrap new opportunities for the development of high-performance safe energy storage devices.

The evolution of the Perovskite solar cells (PSC) has been remarkable with several milestones achieved in recent years. Intensive research is still ongoing to achieve the highly efficient PSCs with enhanced stability. The main problems of perovskite solar cells are relatively low power conversion efficiency (PCE) and less stability. This research work reports the improvement in performance of PSC by utilizing the encapsulation of TiO2 nanotubes with Cs nanoparticles to increase the electron injection rate and thermal stability. In this context, TiO2 Nanotubes and Cs-TiO2 Nanotubes have been synthesized by simple electrochemical anodization technique. SEM, EDX and XRD characterizations were engaged to observe the surface morphology, elemental composition and crystalline structure, respectively. UV/Vis spectra show that Cs-TiO2 nanotubes have higher optical absorption in the visible region than pure TiO2 nanotubes-based samples. The stability of PSC was evaluated by thermal gravimetric analyses (TGA), which showed only 2.5 % weight loss up to 800°C. Furthermore, J-V measurements were also performed, and it was observed that the Cs-TiO2 nanotubes-based PSCs presented an enhanced PCE of 13.24 %, which is higher than those of the PSCs based on pure TiO2 nanotubes. So, an enhanced PCE could be achieved by higher electron injection rate.

The existence and detection of toxic and greenhouse gases at relatively low concentrations play an important role in protecting human beings exposures from intensive gases. To overcome this issue, it is essential to devise gas-sensing devices based on ultrafine-structured nanomaterials. The versatile zeolite imidazolate-based metal-organic frameworks (ZIF-MOF) are effectively synthesized using solvothermal method for superior gas sensing applications. Compared with other target gases measured at wide range of temperatures (50–350 °C) and 10–100 ppm with different gas concentrations, the fabricated gas sensors demonstrate fast response and recovery times (113.5, 111.5 s), strong sensing sensitivity (118.5) and selectivity against NO2 gas at 350 °C. Simultaneously, the polyhedral based MOF gas sensors are considered potential applicants in the development of the NO2 gas sensor industry. This research expands on new insight for high porosity metal-organic frameworks in the industrial environment applications of gas-sensors.

The present paper describes the efficiency of the synthesis of multi-walled carbon nanotubes (MWCNTs), which is achieved through the implementation of a non-standard approach to the preparation of a Ni/MgO catalyst. The catalyst required for MWCNTs synthesis was obtained through chemical vapor deposition method. At the same time, the pre-catalyst was treated by electromagnetic field, ultrasound and microwave waves methods. It was proved that the treatment of the catalyst initial components solution with the electromagnetic field, ultrasound and microwaves contributes to an increase in the yield of the synthesized MWCNTs by 50, 30 and 70%. Besides, ultrasonic treatment may be used if MWCNTs of relatively low degree of a defect are required. The proposed approach is economically feasible since small additional energy costs lead to a more complete conversion of carbon-containing raw materials into the target product at the activation stage. The reported method may be used to prepare MWCNTs of different types economically; leading to its industrial application to produce different types of MWCNTs.

An Ag2O(x)−PrO2(y)/γ-Al2O3 electrocatalyst series (X:Y is for Ag:Pr from 0 to 10) was synthesized, to use synthesized samples in electrochemical applications, a step in fuel cells advancements. Ag2O(x)−PrO2(y)/γ-Al2O3/Glassy-Carbon was investigated for electrochemical oxidation of ammonia in alkaline medium and proved to be highly effective, having high potential utility, as compared to commonly used Pt-based electrocatalysts. In this study, gamma alumina as catalytic support was synthesized via precipitation method, and stoichiometric wt/wt.% compositions of Ag2O−PrO2 were loaded on γ-Al2O3 by co-impregnation method. The desired phase of γ-Al2O3 and supported nanocatalysts was obtained after heat treatment at 800 and 600 °C, respectively. The successful loadings of Ag2O−PrO2 nanocatalysts on surface of γ-Al2O3 was determined by X-rays diffraction (XRD), Fourier-transform Infrared Spectroscopy (FTIR), and energy dispersive analysis (EDX). The nano-sized domain of the sample powders sustained with particle sizes was calculated via XRD and scanning electron microscopy (SEM). The surface morphology and elemental compositions were examined by SEM, transmission electron microscopy (TEM) and EDX. The conductive and electron-transferring nature was investigated by cyclic voltammetry and electrochemical impedance (EIS). Cyclic voltammetric profiles were observed, and respective kinetic and thermodynamic parameters were calculated, which showed that these synthesized materials are potential catalysts for ammonia electro-oxidation. Ag2O(6)−PrO2(4)/γ-Al2O3 proved to be the most proficient catalyst among all the members of the series, having greater diffusion coefficient, heterogeneous rate constant and lesser Gibbs free energy for this system. The catalytic activity of these electrocatalysts is revealed from electrochemical studies which reflected their potentiality as electrode material in direct ammonia fuel cell technology for energy production.

Al2O3-Cr2O3 refractories are completely substitution solid solutions and can effectively resist slag erosion when used as an industrial furnace lining. In order to provide suitable chromium corundum refractory with excellent slag resistance and mechanical properties for smelting reduction ironmaking, Al2O3-Cr2O3 samples with different mass percentages (0, 10, 20, 30, 40 wt.%) of Cr2O3 were prepared by a normal pressure sintering process to study its sintering properties, mechanical properties, thermal shock resistance, and microstructure. The results of densification behavior showed that the introduction of Cr2O3 deteriorates the compactness, the relative density and volume shrinkage rate of the composite material decrease with the increase of the Cr2O3 content, and the apparent porosity increases accordingly. In terms of mechanical properties, the hardness, compressive strength, and flexural strength of Al2O3-Cr2O3 material decrease gradually with the increase of Cr2O3. After 10 and 20 thermal shock cycles, the flexural strengths of the samples all decreased. With the increase of Cr2O3 in these samples, the loss rate of flexural strength gradually increased. Considering the slag resistance and mechanical properties of the composite material, the Al2O3-Cr2O3 composite refractory with Cr2O3 content of 20–30% can meet the requirements of smelting reduction iron making kiln lining.

Herin, we prepared silver NPs using jasmine flower extract. The green synthesis process reports a eco-friendly, nontoxic, cost-effective and simple approach to the synthesis of metal and metal oxide nanoparticles. Extract of jasmine flower acts as capping as well as stabilizing agent. The average crystalline size of the XRD pattern is estimated to be 40 nm. FT-IR (Fourier Transform Infrared) spectra confirm the existence of Ag NPs. The UV-Visible spectrum exhibits an absorption peak of between 380 and 440 nm. Structural analysis for silver nanofibers reveals with SEM and TEM technique. The antimicrobial activity of silver NPs was tested for both grams positive and negative bacteria by Agar well diffusion method. Methylene blue is used as a pollutant dye. Silver nanoparticles result in a maximum degradation efficiency of 78% at the end of 120 min.

Malaysia has continued to increase the explosive growth rate of its industries in recent years. The rise of globalization has driven Malaysia’s economic development at the ecosystem level of pollution. This research study explores the relationship of CO2 emissions, gross domestic product, globalization, industrialization, and trade openness for Malaysia by using annual data for 1971–2016. By applying the ARDL bound testing approach, the estimates infer that CO2 emissions have steadily risen with high economic growth and affirm the U-shaped environmental Kuznets curve (EKC). Globalization’ index and trade openness surge Malaysian CO2 emissions. While industrialization has a statistically significant negative impact on CO2 emissions. The VECM Granger causality infers the unidirectional causality running from economic growth, globalization, industrialization, and trade openness to CO2 emission in the short-run Finally, this study provides some suggestions to Malaysian policymakers for devising carbon emission reduction strategies.

High-loading electrode based on aluminum foil is difficult to use in solid-state lithium battery because of its low conductivity, which affects the areal specific capacity and energy density of the battery. In this work, three dimensional through-hole aluminum foam was used as current collectors of high-loading LiNi0.6Co0.2Mn0.2O2 (NCM622) electrodes and for first time applied in solid-state lithium battery. The use of aluminum foam instead of commercial aluminum foil can greatly increase the areal specific capacity, the areal specific capacity was increased from 0.4 mAh/cm2 to 1.3, 1.4, 1.6 mAh/cm2 for different thickness of aluminum foams. At the same time, the energy density of solid-state battery composed of aluminum foam-based electrodes are 2.5~3 times that of aluminum foil-based solid-state battery. The aluminum foam has a significant application prospect as electrode current collector for solid-state batteries.

Hydrazine, a highly toxic compound, is used worldwide in industries as a reducing agent for numerous applications. It has a harmful effect on humans and the environment; therefore, advanced analytical techniques are utilized to monitor hydrazine levels to minimize exposure. In this work, we report the fabrication of vertically oriented ZnO nanosheets based solution-gated field-effect transistor (FET) sensor for the low concentration detection of hydrazine. The ZnO nanosheets between source-drain electrodes were encapsulated with Nafion matrix to enhance stability and selectivity during hydrazine detection. The ZnO nanosheets-based solution-gated FET sensor’s sensing properties are compared with and without different concentrations of hydrazine in buffer solution. Conductance of the solution-gated FET hydrazine sensor showed substantial change upon addition of different concentrations of hydrazine. The fabricated hydrazine sensor exhibits high sensitivity (12150 μA μM−1 cm−2) in the linear response range of 5–110 nM. The low detection limit (∼1.2 nM; signal-to-noise (S/N) ratio of 3), high sensitivity, stability, and reproducibility are due to the direct growth of nanosheets that provide the controlled morphology and enhanced surface area. Besides, solution-gated FET hydrazine sensor was successfully applied to detect hydrazine in water samples for practical validation of developed hydrazine sensors.

This article reports the oxidation of cumene by H2O2 in the presence of CO2. It describes the role played by carbon dioxide on the course of the reaction. The reaction was catalyzed by unsupported Co1.5PW12O40 and supported on activated carbon. The prepared materials were characterized by ICP, IR, XRD and UV. Analysis of the reaction products by gas chromatography coupled with mass spectrometry and gas chromatography showed that 2-phenyl-2-propanol and acetophenone were the main products of the reaction. Activated carbon significantly increases conversion by increasing Co1.5PW12O40 accessibility to cumene molecules. The improvement in the conversion and selectivities of 2-phenyl-2-propanol and acetophenone by the use of the oxidizing system H2O2/CO2compared to the use of H2O2 alone or CO2 alone is due to the role of the percarbonate entity HCO 4 − formed by reaction between H2O2 and CO2. Oxidation by large amounts of H2O2 decreases the conversion by decreasing the solubility of cumene in the resulting aqueous medium. An increase in the reaction time resulting in a decrease in the concentration of H2O2 and leaving the effect of the predominant CO2 accentuates the cracking reactions.