Binary Composites Research Articles

Graphene Reinforced Binary Resin-Based Carbon Foam Composites for Mechanical and Electromagnetic Interference Shielding Applications

Graphene Reinforced Binary Resin-Based Carbon Foam Composites for Mechanical and Electromagnetic Interference Shielding Applications

Physicochemical and photocatalytic properties of Ag2CrO4/Fe2O3/CeO2 ternary nanocomposite.

The study presents Ag2CrO4/Fe2O3/CeO2 ternary nanocomposite, based on Fe2O3/CeO2 binary composites, which demonstrated excellent photocatalytic performance in the photodegradation of methylene blue under solar irradiation. The Ag2CrO4/Fe2O3/CeO2 nanocomposites was orthorhombic, ilmenite, and cubic-fluorite phases of Ag2CrO4, Fe2O3, and CeO2, respectively, according to the XRD examination. A strong bond between Ag2CrO4, Fe2O3, and CeO2 within the nanocomposite was demonstrated by the SEM and TEM investigations. Moreover, it was discovered that the coupling of Ag2CrO4 and Fe2O3 caused a red shift and moved CeO2 absorption edge from the UV to the visible spectrum. The reason behind this is that the band gap of CeO2 reduced 2.85 to 2.69 eV and the absorbance band intensity increased in visible region. Utilizing visible light, Ag2CrO4/Fe2O3/CeO2 ternary nanocomposites exhibit enhanced photocatalytic properties (98.90%) for the degradation of methylene blue (MB) within 100 min. The long-term reliability and recyclability of the photocatalyst were explored through 3 successive cycles. An active radical quenching test was conducted to elucidate the involvement of O2 - and OH which are the primary reactive species in the photocatalytic breakdown of MB. Ag2CrO4/Fe2O3/CeO2 ternary nanocomposites displayed notable improvements in photodegradation activity, making them well suited for the effective removal of hazardous dyes present in textile effluents.

Bi2WO6 and TiS2 composite nanostructures displaying synergetic boosted energy storage in supercapacitor

The enhancement in the capacitance of a supercapacitor has been successfully achieved by synthesizing Bi2WO6 (BW), TiS2 (T), and Bi2WO6/TiS2 (BW/T) composites utilizing the hydrothermal process. The possible growth mechanism has also been presented. The morphological and structural characteristics of the cultivated samples were observed using FT-IR, XRD, SEM, EDS, and UV–vis spectroscopy techniques. TiS2 nano platelets uniformly dispersed across the hierarchically opened surface of Bi2WO6 in the synthesized hierarchical composite. This leads to an increase in surface porosity and surface area, which in turn enhances the transport of electrons and ions on the composite BW/T surface. The optimal electrode BW/T@40 % composite electrode shown a substantial enhancement in particular capacitance (1153.3 F/g) compared to the separate BW (523.7 F/g) and T (453.3 F/g) electrodes due to its rapid ion transfer, many active sites on its large surface area, and strong synergistic impact. Furthermore, the BW/T@40 % combination demonstrated exceptional stability, with over 92 % of its capacitance maintained after 4500th cycles and b value (0.71) proved the supercapacitor behavior. Therefore, BW/T@40 % binary metal oxide and sulfide composites exhibit improved specific capacitance and greatly prolonged life-cycle, confirming its potential use in high-performance energy storage devices.

Enhanced photocatalytic degradation of harmful pollutants by MoO3/SiO2/MXene nanocomposite powder catalyst

The search for materials to treat wastewater is especially crucial. Herein, we have prepared 1D molybdenum oxide (MoO3) nanobelts through a hydrothermal approach. The binary (MoO3/SiO2) and ternary composites of MoO3/SiO2/MXene were synthesized via ultrasonication route. The as-prepared MoO3, MoO3/SiO2, and MoO3/SiO2/MXene composites were employed to investigate the photocatalytic behavior of two organic dyes, methyl orange (MO) and crystal violet (CV). The % degradation of MO in the presence of MoO3 nanobelts and MoO3/SiO2 was calculated to be 48.9 % and 74.4 %, respectively. In the case of CV dye, the degradation (%) was observed at 53.7 % and 75.9 %. The MoO3/SiO2/MXene composite revealed the best photocatalytic behavior against both MO and CV dyes by removing 94.7 % and 97.7 % under visible light irradiation. The rate constant values of MoO3 nanobelts, MoO3/SiO2 and MoO3/SiO2/MXene composite for MO dye were calculated to be 0.00568 min−1, 0.01156 min−1, and 0.02399 min−1 and for CV dye 0.00679 min−1, 0.01208 min−1, and 0.02798 min−1 respectively. A scavenging test was carried out to monitor the main photo-active species that take part during the photocatalysis and hydroxyl radicals were found to be the highly active species during whole photodegradation progression. The SiO2 particles function as a good adsorbent medium and transfer the adsorbed organics toward more active sites to advance the reaction. 2D MXene nanosheets, as good conductors, reduce the recombination rate of charges, offer large surface area, and facilitate fast transfer of charges. The results suggest that MoO3/SiO2/MXene composite is a potential contender for wastewater remediation applications.

Investigating the Effects of PU-Based Back-Coating with Boric Acid and Titanium Dioxide Additives on Flame Retardancy Levels and Comfort Properties of 100% Cotton Denim Fabric

Abstract This study aimed to develop a cost-effective and resource-efficient application to enhance the thermal stability, flame retardancy, self-cleaning, and antibacterial properties of cotton denim fabrics through a single-step, flexible, and simple polyurethane (PU) based back-coating method, ultimately increasing the use of denim fabrics in daily and work clothes thanks to the increased functionality. This method utilizes boric acid (H3BO3) and a binary composite of H3BO3-titanium dioxide (TiO2) as functional additives while considering comfort parameters. Limiting oxygen index (LOI) and vertical burning tests were conducted to explore the thermal stability and flame retardancy of the samples, while assessments of air permeability, water vapour permeability, thermal resistance, and thermal absorptivity were performed to investigate the comfort properties. Comparing two kinds of back-coated denim fabrics, H3BO3-TiO2 back-coated cotton fabric showed the best flame retardancy with the lowest char length (45 mm) and highest LOI (27%). The air permeability values of back-coated fabrics decreased by approximately half compared to the untreated denim fabric. Although the water vapour permeability values decreased, they were less affected by the coating. Coating application reduced thermal conductivity and thermal absorbency, resulting in more thermally resistant denim fabric. This study demonstrates the potential utility of a PU-based coating incorporating TiO2 and H3BO3 on traditional cotton denim fabrics to enhance flame resistance while minimizing any adverse effects on the overall thermal comfort of the fabric.

Exploring the electrochemical synergy of metal sulfides and metal-organic framework composite as hybrid supercapacitor electrodes

Metal-organic frameworks (MOFs) are promising electrode materials however, they continue to seek improvements in both energy density and electrical conductivity. Within a wide array of available metal nodes and linkers, the task of refining and attaining a profound comprehension of charge storage mechanisms is still to accomplish. Herein nickel sulfide and nickel MOF were synthesized via hydrothermal method, their properties were investigated, and a binary composite was developed due to the high resistance of pristine MOFs. This composite demonstrated exceptional specific capacity of 787.8 C/g at cost of 2.0 A/g. To leverage real-world applications, a supercapattery was fabricated using the NiS/Ni-MOF as the positive electrode material and activated carbon as the negative electrode material. The device possesses maximum specific energy of 64.67 Wh/kg and maximum specific power of 3200 W/kg together with capacity retention of 91 % after 5k charge-discharge cycles. To validate results, semi-empirical approach using Dunn’s model and power law is subjected to investigate the capacitive and diffusive contributions and b-values. This study shows that the binary composites of metallic sulfides with MOFs can possess potentials for their applications in real devices.

Enhanced photocatalytic performance of rGO/UiO-66(Zr)/Ag3PO4 composite for degradation of methyl orange (MO) under visible light irradiation

Industries like textile, plastic, pulp, and paper produce dye-containing waste waters that have harmful effect on the environment as well as human health. This work presents a series of binary and ternary composites formed by reduced graphene oxide (rGO), silver phosphate (Ag3PO4) and the nanocrystalline MOF, UiO-66(Zr). The composites exhibit the best of their catalytic features to achieve efficient photocatalysis to remove the model dye methyl orange (MO) from aqueous solution as well as dyes from a real industrial wastewater effluent. The composites were prepared under sustainable conditions, at room temperature. XRD characterization shows that the prepared MOF is one of the most nanocrystalline reported UiO-66(Zr), becoming even more nanocrystalline in the composite formation. Different physicochemical characterization techniques indicated the existence of such interaction. Thus, DRS-UV-vis spectroscopy makes clear the reduction of the band-gap of the composites compared with the individual components; the band intensity of the photoluminescence (PL) spectra is substantially reduced in composites, confirming the diminution of electron-hole recombination; and electrochemical impedance spectroscopy (EIS) shows that the electrodes modified with ternary composites present faster electron transfer ability. The selected composite rGO/UiO-66(Zr)/Ag3PO4 exhibits high efficiency on the photodegradation of the model MO dye compared to the binary and single counterparts. It could be attributed to its high surface area, enhanced visible light absorption, efficient charge transfer process, as well as the synergetic effect between its components. A degradation mechanism is proposed based on the estimated band-gaps and on the scavenging study with strategically-chosen species.

Enhanced light absorption and charge carrier’s separation in g-C3N4-based double Z-scheme heterostructure photocatalyst for efficient degradation of navy-blue dye

ABSTRACT Effective wastewater treatment is essential due to the dye environmental threats. Photocatalysis offers an eco-friendly dye degradation solution. Herein, we report a double Z-scheme photocatalyst, i.e. LaFeO3/Boron-doped g-C3N4/Fe2O3 (LFO/B-CN/FO), fabricated via a hydrothermal method. The formation of this ternary system is supported by structural, surface, and morphological analyses. Differential scanning calorimetry and thermal gravimetric analysis demonstrated the crystallization behavior of the composite. Because of synergetic effects in the ternary composite and boron doping, the optical band gap energy is reduced to 1.6 eV. Under visible light irradiation, the LFO/B-CN/FO nanocomposite degraded navy-blue dye by 98% in 130 min at neutral pH, surpassing CN, B-CN, and binary composites of B-CN with LFO and FO. The degradation process was rationalized using pseudo-first- and pseudo-second-order kinetic models, which confirmed high catalytic efficiency. The double Z-scheme heterojunction enhanced light absorption, charge separation, and carrier lifetime, hence improving the photocatalytic activity. Overall, the as-fabricated LFO/B-CN/FO ternary composite outperformed reference catalysts in terms of chemical reactivity, optical characteristics, and electrical performance. This work opens up a new route for the design and fabrication of double Z-scheme ternary composite photocatalysts for potential wastewater treatment and renewable energy applications.

Heteroatom doped cellulose nanocrystals (CNC) with chiral nematic liquid crystal interface for high efficiency removal of ciprofloxacin

The increasing contamination of water systems by ciprofloxacin (CIP) has become a growing concern. The photocatalysis approach offers a promising strategy for the effective removal of CIP. In this study, MSx/CNC (MSx, M = Co, Ni, Cu) binary composites with chiral catalytic interfaces were prepared by chemical precipitation and the composite M0-MSy/CNC was prepared by energetic β-particle bombardment. The XPS results confirmed the successful construction of C–O−M bonds. TEM results clearly revealed the generation of sulfur vacancies (Sv) in the composites. The M0-MSy/CNC/peroxymonosulfate (PMS) photocatalytic system was also constructed in this study. The results of the application experiments showed that the Co0-CoSy/CNC/PMS system had an excellent degradation effect on CIP, which reached 100 % at 1.5 h of open light. The degradation kinetic constants of Co0-CoSy/CNC/PMS were 4.26 times higher than those of CoSx/CNC/PMS. In addition, EPR showed that the Co0-CoSy/CNC/PMS system generates ‧OH, ‧SO4−, ‧O2−, and h+ radicals to co-remove CIP. This study also elucidated the major intermediates of photocatalytic degradation of CIP at the chiral catalytic interface using LC-MS analysis. This work provides insights into the coupled application of photocatalysis and PMS activation in the remediation of aqueous environments.

The performance of CO2 reduction by dielectric barrier discharge plasma coupled Cu-Ni binary silicon-based composites

As a major greenhouse gas, the rational conversion and utilization of CO2 can help reduce carbon emissions and mitigate the greenhouse effect. In this study, mesoporous SiO2 as a carrier, with CuO and NiO employed to construct a binary metal composite silica-based catalyst, coupled with dielectric barrier discharge (DBD) plasma, for the conversion of CO2. Physicochemical analysis confirmed the successful introduction of CuO into the mesoporous SiO2. NiO and CuO bimetals were dispersed on SiO2 surfaces with large specific surface areas, ensuring an optimal distribution of metal oxide. Gas chromatography was utilized to investigate the performance of DBD-coupled x%CuO-3 %NiO/Si for CO2 conversion. The results indicated that the CuO-NiO binary composite silica catalysts significantly improved CO2 conversion, CO yield, and energy efficiency compared to the monometallic 3 %NiO/Si materials. Further microstructural analysis of the 9 %CuO-3 %NiO/Si catalyst revealed near-elliptic particles with dimensions of 200 by 500 nm and a large number of irregular fine particles attached to the surface. When the CuO loading reached an optimal level and the input power was set at 30 W, the energy efficiency of the 9 %CuO-3 %NiO/Si catalyst increased by 119.6 %. The CuO-NiO binary composite Si-based catalyst developed in this study boasts simple operation and environmental friendliness, making it highly significant for CO2 treatment.

CeO2 nanospheres incorporated with Bi2MoO6/g-C3N4 enhanced photocatalysis towards environmental pollutant Rhodamine B removal.

We have adopted a novel CeO2/Bi2MoO6/g-C3N4-based ternary nanocomposite that was synthesized via hydrothermal technique. The physiochemical characterization of as-prepared samples was examined through various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy TEM, photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), and ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. In addition, the photocatalytic performance was carried out by degradation of Rhodamine B dye under visible light irradiation using this nanocatalyst. The ternary nanocomposite achieved 94% of the degradation efficiency within 100min which is higher than the pristine and binary composites under the predetermined condition pH = 7, Rhodamine B dye = 5mg/L, and catalyst concentration = 150mg/L. The experimental synergetic effect of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite has been ascribed to the interfacial charge carrier migration between CeO2, Bi2MoO6, and g-C3N4. The optical absorption range of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite was enhanced, and the band gap was reduced up to 2.2eV. In addition, scavenger trapping experiment proves that the super oxide anions (O2-.) and photogenerated holes are the major active species. The reusability and stability experiment proved the CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite keeps good durability during the photocatalytic degradation process after the five successive cycles. Furthermore, based on the results, the charge carrier transfer photocatalytic mechanism was also discussed. This CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite may offer the cheapest material and extend the great opportunity for clean and environmental remediation approach under the visible light irradiation.

An efficient NiS-ReS2/CdS nanoparticles with dual cocatalysts for photocatalytic hydrogen production

The construction of heterojunctions is one of efficacious ways to improve the charge transfer and suppress the recombination of photoexcited electron-hole pairs for enhancing reactive activities of photocatalysts. Ternary NiS-ReS2/CdS composites are synthesized via a one-step hydrothermal method and the heterojunction nanostructures are achieved. The NiS-ReS2/CdS photocatalyst exhibits the superior photocatalytic activity with a hydrogen production rate up to 139 mmol g−1 h−1, which is much higher than binary composites and pure CdS. The contributions of the dual cocatalysts NiS and ReS2 are verified to narrower bandgaps, lower resistances and increase photocurrent density of NiS-ReS2/CdS, promoting the absorption of visible light and the migration of photoinduced electrons. The NiS-ReS2/CdS heterostructures provide a possible dual Z-scheme path for the rapid transfer of electrons. The tailoring of the dual cocatalysts is effective to improve the photocatalytic hydrogen production.

Construction of Binary Matrix for Efficient Room Temperature Phosphorescence Emission

AbstractDespite the extensive research on room temperature phosphorescent (RTP) materials, it remains a great challenge to further improve the photophysical properties of RTP materials. In this study, the RTP emission of guest molecule is significantly enhanced by constructing binary matrices containing cyanuric acid (CA) and amino‐containing compounds. Systematic studies show that the strong interaction between the two components of binary matrix induced variations in the guest molecular configuration and excited state electron distribution, thus facilitating the production of more triplet excitons. Furthermore, the binary matrix also exhibits stronger domain‐limiting effect compared to the CA mono‐matrix, effectively inhibits the energy loss of triplet excitons due to quenching and non‐radiative transitions. The prepared binary matrix RTP materials present ultralong phosphorescence lifetime and high phosphorescence quantum yield (up to 3.21 s and 7.31%, respectively), and even achieve bright RTP emission in a variety of organic solvents and aqueous media. Moreover, the RTP emission intensity of the best binary matrix composite can reach more than 28 times that of the CA mono‐matrix composite, and the RTP lifetime can be extended by 1.51 s.

The Hydrothermal-Assisted Approach Improves the Photocatalytic and Energy Storage Performance of Novel CuSe-TiO2-GO Composite.

This study reports a novel CuSe-TiO2-GO composite, synthesized by a facile hydrothermal method at a controlled temperature, and investigates its electrochemical performance for supercapacitors (SCs) and photocatalytic behavior for degrading methylene blue (MB) dye. The compositional phase structure and chemical bond interaction were thoroughly investigated. The as-fabricated pristine, binary, and ternary composites underwent comprehensive characterization employing spectroscopic techniques and electrochemical analysis. Compared with pure and binary compounds (CuSe, TiO2, and binary CuSe-TiO2 composites), the ternary CuSe-TiO2-GO composites demonstrated a high degradation efficiency while degrading MB in less than just 80 min (240 min, 100 min, and 140 min, respectively). The photocatalytic activity of the ternary CuSe-TiO2-GO composites is enhanced due to the highly positive conduction band of CuSe, leading to the quick excitation of electrons to the conduction band of CuSe. Subsequently, graphene oxide (GO) left holes on the photocatalyst surface for MB, as GO assisted the photoexcited electron-hole pairs, resulting in enhanced photocatalytic performance. The CuSe-TiO2-GO electrode for the supercapacitor indicates a 310.6 F/g and 135.2 F/g capacitance when the discharge current upsurges from 1 to 12 A/g. The good photocatalytic and energy storage performance is due to the smaller charge transfer resistance, which promotes efficient separation of electron-hole pairs.

Densification, microstructure, and wear properties of TiB2-TiC-GNP and TiB2-TiC-BN composites

In this study, TiB2–TiC, TiB2–TiC-GNP, and TiB2-TiC-BN composites were produced via spark plasma sintering (SPS). The densification and sintering behavior, phase and Raman spectroscopy analyses, microstructural properties, Vickers microhardness, and wear behavior of the binary and ternary composites were investigated. The addition of various amounts of TiC to TiB2 resulted in nearly complete densification. The TiB2–TiC-GNP specimens exhibited a relative density of more than 99 %; in contrast, the addition of BN did not contribute to the densification. The Vickers hardness of the GNP-added composites was ∼25 GPa, whereas hBN addition to the matrix decreased the hardness to ∼22 GPa (∼9 % decrease). According to the wear test, the addition of GNPs did not result in a significant change in the TiB2–TiC matrix; however, the addition of hBN increased the specific wear rate of the matrix by ∼100 %. The GNPs did not have a negative effect on the densification, microstructural, or mechanical properties, such as the Vickers hardness and wear resistance. Hence, they were determined to be a more suitable sintering aid for matrix composition than hBN.

Synergistic adsorption performance from binary and ternary composites comprising ZnO, PVA, and crab shell chitosan for azo and non-azo dyes

ABSTRACT Chitosan is a good adsorbent but has poor effectiveness against some dyes. Therefore, in this study, we synthesized composite materials of prepared crab shell chitosan with ZnO and PVA to improve adsorption efficiency. The ZnO/CTS and ZnO/PVA/CTS composites were synthesized by dissolving the components into a solution with the help of ultrasound and hydrothermally neutralizing it for 3 h. The obtained composites and crab shell chitosan were characterized by methods such as GPC, FTIR, XRD, and SEM. Adsorption experiments were conducted in batch form and only sampled once under each condition. The results showed the molecular weight of crab shell chitosan is around 105 g/mol and quite homogenous in size, and the embedded nanorod-like ZnO in the composite is around 200 nm in sizes. The adsorption of the dyes Indigo Carmine (IC), Alizarin Yellow (AY), and Thymol Blue (TB) onto the composites was highest compared to the single adsorbent and ranked in descending order: ZnO/CTS+AY > ZnO/PVA/CTS+IC > ZnO/CTS+IC > ZnO/PVA/CTS+AY > ZnO/CTS+TB > ZnO/PVA/CTS+TB, which corresponds to qmax of 285.7 mg/g, 227.3 mg/g, 208.3 mg/g, 188.7 mg/g, 60.6 mg/g, and 50.3 mg/g, respectively. In addition, the adsorption kinetics of all cases followed the pseudo-second-order adsorption model, it implies that the rate of adsorption is proportional to the square of the number of unoccupied sites.

A novel LaFeO3/g-C3N4/Ag3PO4 dual Z-scheme heterojunction with enhanced light absorption, charge carrier separation and transfer capacity for photodegradation of antibiotics

The effective separation of photogenerated carriers is still a key problem to be overcome in the preparation of efficient green photocatalysts. In this work, A novel ternary composite LaFeO3/g-C3N4/Ag3PO4 (LgA) with dual Z-scheme heterojunction structure photocatalyst was constructed by combining LaFeO3 with excellent photoelectric conversion rate and Ag3PO4 with high-quantum yield on the surface of g-C3N4 by electrostatic attraction and in-situ co-precipitation. The serial characterization confirmed that there were close heterojunction interfaces and well-matched band structures among them, which was conducive to improving the separation efficiency of photogenerated electron-hole pairs. The photocatalytic results showed that the photocatalytic degradation performance of LgA-4 composites for ciprofloxacin hydrochloride (HCIP) was significantly superior to that of g-C3N4, LaFeO3, Ag3PO4 or their binary composites, and the degradation efficiency could reach 90.2 %, which could be mainly attributed to the construction of dual Z-scheme heterojunction with large valence bands oxidation surface, improved the light absorption capacity and promoted the separation of photogenerated electron-hole pairs (e−-h+). LgA-4 also had good stability and efficient universality. Furthermore, the photocatalytic mechanism of HCIP photocatalytic degradation by LgA-4 heterojunction was particularly discussed according to the results of characterization, free radical quenching and ESR experiments. The potential degradation pathways for HCIP by LgA-4 were proposed as well based on the degradation intermediates detected by Ultra-high Performance Liquid Chromatography-Mass Spectroscopy (UPLC-MS), HCIP degradation was confirmed a process of reduced ecotoxicity. These results provided a facile pathway for the preparation and application of high efficiency photocatalysts in water pollution control.

Graphitic carbon nitride sheets sandwiched metal oxides: A novel platform for S-Scheme heterojunction generation for efficient photodegradation of volatile organics

This study reports the preparation of new kind of S-Scheme heterojunction (SSHJ) photocatalyst by distributing two semiconducting metal oxides (titanium dioxide and ZnO) onto the surface of graphitic carbon nitride (G-CN) two dimensional (2D) sheets. The composite photocatalysts, designated as T/Z@ GCN SSHJ, were prepared with different mass ratios of T,Z and G-CN.X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), field emission scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy were used to characterize the microstructure, morphology, chemical composition, electronic states, and optical properties of the T/Z@ GCN SSHJ composite. TEM image of the typical T/Z@ GCN SSHJ composite shows the presence of distribution of particles with sizes in the range 40–80 nm on the lamellar surface of G-CN inferring the formation of a heterostructure Z(0 D) /G-CN(2D)/T(0D) SSHJ composite. The comparison of the core level XPS spectrum of Ti 2p, Zn 2p, C1s, O1s and N1s of T/Z@ GCNSSHJ composite with the binary composites (T+G-CN and Z+G-CN) and pristine components clearly suggests that that Z, T and G-CN are kept together through van der Walls interactions. The T/Z@ GCN SSHJ composite photocatalyst with T: Z: G-CN mass ratio of 1.0: 0.80: 0.12 exhibited enhanced photocatalytic degradation (%) over binary and pristine single components for all the tested volatile organic compounds (VOCs), namely, acetaldehyde (ACD), ethyl acetate (EA), toluene (T) and benzaldehyde (BA). On comparing the % removal of VOCs after 20 minute of light irradiation, BA showed the highest removal % (94.3 %) and the others take the following order: ACD (70.9 %) >EA (56.45 %)> TL (40.12 %). The study explains the enhanced performance of T/Z@ G-CN HJ composite towards VOC photodegradation in terms of S-Scheme based charge transfer and internal electric field driven efficient charge separation. The charge transfer process of T/Z@ GCN HJ composite photocatalysts is discussed through S-Scheme HJ formation and supported with electronic states and band energy levels of the constituent components derived through the results of XPS and DRS analysis. This study gives insight into the design for regulating the hetero-interfaces for enhancing the photocatalysis and expected to further understand into charge transfer mechanism at multi-junction-based photocatalysts.

Predicting rapid growth behavior in solidified eutectic ceramic composites using infrared thermal imaging and thermal field simulation during laser directed energy deposition

Cylindrical Al2O3/GdAlO3 binary in situ oxide eutectic ceramic composite, with a glossy surface and high relative density, has been fabricated using the laser directed energy deposition method (LDED) with optimized process parameters. In a novel and innovative approach, infrared thermal imaging and the finite element method (FEM) have been combined for the first time to capture the temperature field distribution across different regions of the molten pool during the LDED processing of the binary oxide eutectic ceramic composite, thereby synergistically obtaining the solidification characteristics. With an increase in the scanning rate, the temperature gradient within the molten pool decreases from 3.38 × 105 K/m to 1.62 × 105 K/m, while it shows minimal variation with fluctuations of the laser power. Under the conditions of high temperature gradients and rapid non-equilibrium solidification characteristic of LDED, the Al2O3/GdAlO3 (GAP) binary eutectic ceramic composites, which exhibit typical high melting entropy and faceted/non-faceted growth modes, exhibit complex and variable microstructure morphology. A combination of regular/irregular models, including JH (Jackson-Hunt), MK (Magnin-Kurz), GK (Guzik-Kopyciński) and TMK (Trivedi-Magnin-Kurz), is employed to investigate and predict the growth and transformation of microstructures. The JH and TMK models fairly predict the rod-like regular eutectic microstructure inside the colony and lamellar regular eutectic within adjacent layers, respectively. The “Chinese-script” irregular microstructure at the interface between the colony and the layers is consistent with the MK and GK models. The as-deposited eutectic ceramic composite presents ultra-fine microstructures, clear and strongly bonded phase interfaces with low strain energy, contributing to its microstructure stability after high temperature heat treatment at 1773 K for 200 h, and achieving a minimum microstructure coarsening rate of 0.0005 μm/h.

A microwave-regenerable multi-walled carbon nanotube/polyaniline/Fe3O4 ternary nanocomposite for quantifiable sorption of cationic and anionic dyes

The coexistence of toxic dyestuffs in the aquatic environment requires the urgent development of a multifunctional sorbent for their efficient sequestration from aqueous solutions. To achieve this objective, a ternary nanocomposite consisting of an amphoteric, multi-walled, carbon nanotube/polyaniline/magnetite (MWCNTs/PANI/Fe3O4) was successfully synthesized through the co-precipitation of magnetite (Fe3O4) onto the surface of a pre-existing binary composite of MWCNTs/PANI. The structural and morphological features of MWCNTs/PANI/Fe3O4 were scanned using a variety of analysis methods: Fourier transform infrared spectroscopy; both scanning and transmission electron microscopies; energy-dispersive X-ray analysis; thermogravimetric analysis. The capacity of MWCNTs/PANI/Fe3O4 to adsorb cationic dye (Methylene blue, MB), and anionic dye (Congo red, CR) were discerned inclusively under variable operational parameters. The sorption processes of both MB and CR dyes onto MWCNTs/PANI/Fe3O4 were pH-dependent. The sorption process of both dyes onto MWCNTs/PANI/Fe3O4 was reported to fit with the Langmuir model, while the sorption kinetics fitted with the pseudo-second-order kinetic model. The prepared MWCNTs/PANI/Fe3O4 exhibited satisfactory sorption capacities of 142.85 mg g−1 (initial solution pH (pH0): 2.94) and 166.66 mg g−1 (pH0 = 10.03) of the CR and MB dyes, respectively. Dye adsorption followed the monolayer chemisorption phenomenon. The sorption process was exothermic. The application of microwave irradiation caused effective regeneration, and this finding confirmed the renewability of the composite for at least 4 successive sorption/desorption cycles. Using MWCNTs/PANI/Fe3O4 ternary nanocomposite in dye removal looks promising, as its high adsorption capacity, magnetic properties, and renewability offer an efficient, sustainable, and easily recoverable solution for removing dyes from wastewater.