ZhongT Jiang

In this paper we report an all-aqueous fluid-dynamic exfoliation route to low-defect few-layer graphene (FLG) using the non-ionic surfactant Triton X-100. Systematic variation of surfactant concentration (1-5 wt%) and processing time (0.5-1.5 h) revealed a quantitative interplay among stability, defect, and layer. Raman spectroscopy and 2D band Lorentzian modeling revealed that the few-layer graphene (FLG) predominantly consists of four layers, with very low defect ratios (I-D/I-G = 0.02-0.11; I-2D/I-G = 0.18-0.30). Raman imaging confirmed spatially uniform G band intensity, while the edge-activated D band signals indicated residual edge defects characteristic of shear-cleaved flakes. Transmission electron microscopy and particle size analysis yielded lateral sizes of similar to 1.29-1.43 mu m with a narrow distribution. Fourier transform infrared spectroscopy verified that the defects were not oxidation-derived, while UV-Vis showed graphene Ti-Ti absorption at 270-276 nm. This work establishes a short-duration, low-cost, and solvent-free approach for producing stable FLG suitable for liquid-phase applications and provides process-structure metrics for benchmarking across exfoliation studies.

The synthesis of the ZnO-biochar composite from palm kernel shell biomass waste has been accomplished through the utilization of the solvothermal method, yielding a satisfactory outcome. The resulting composite, a combination of ZnO and biochar, has been utilized in the degradation of methylene blue waste compounds. The objective of this research is to synthesize ZnO-biochar composites from palm shells, and to determine the optimal solvothermal temperature and duration. This research was initiated with the preparation of palm shells into biochar. Subsequently, the ZnO-biochar composite was synthesized with variable solvothermal temperatures and solvothermal times. The ZnO-biochar composite was characterized using analytical techniques including SEM-EDX, FT-IR, XRD, BET and UV-vis DRS. The most effective degradation of methylene blue was exhibited by the ZnO-biochar composite sample synthesized at a solvothermal temperature of 180 ̊C and a solvothermal time of 10 hours, achieving a degradation of 88.29%. The enhanced photodegradation performance of this composite sample is attributed to its high surface area, capacity for visible light absorption, and the dimensions of the active crystals, which can account for the high performance of the ZnO-biochar composite for photocatalytic degradation.

This study presents an environmentally friendly and scalable method for synthesizing high-quality few-layer graphene (FLG) through a combination of turbulence-assisted shear exfoliation (TASE) and high shear exfoliation (HSE) techniques. By systematically varying the high-shear mixer (HSM) speed (3000–5000 rpm) and processing time (1–3 hours), we precisely controlled key material attributes, including the number of graphene layers, crystallinity, lateral size, and defect density. Optimal conditions (5000 rpm, 3 hours) resulted in FLG with ~2–3 layers, confirmed by a symmetric 2D peak with a full-width at half-maximum (FWHM) of ~35 cm⁻¹ and a high I2D/IG ratio (~0.6), indicating excellent structural integrity. The ID/IG ratio (~0.1) further verified the presence of minimal defects, predominantly edge vacancies rather than oxidative disruptions. Raman imaging revealed a dominance of zigzag edge chirality, while TEM and PSA analyses demonstrated control over lateral size (~396.5 nm) and particle uniformity. The application of household dishwashing liquid as a green surfactant innovatively enabled selective and pure exfoliation. This work highlights how precise modulation of shear parameters can directly influence graphene quality, paving the way for sustainable large-scale production of low-defect FLG.

The increasing prevalence of healthcare-associated infections from multidrug-resistant bacteria presents a growing challenge due to their high transmissibility, and resistance to traditional antimicrobial strategies. In this study, we introduce an innovative dual-mode antibacterial strategy through the development of novel surface coatings on glass substrates, offering a proof-of-concept solution for enhanced infection control. Our approach uniquely combines the light-active methylene blue silane (MBS1) dye with the potent antimicrobial compound dimethyloctadecyl[3-(trimethoxysilyl)propyl] ammonium chloride (QAS) into silica nanoparticles (SNPs) to create multifunctional antibacterial surface coatings. The distinct use of silane-functionalized MB and QA enables strong covalent bonding with silica nanoparticles, while the robust silane chemistry ensures durable adhesion of SNPs to the glass substrates. While MBS1–SNP coatings generated highly hydrophilic (CA = 28°), light-active surfaces, combination of QAS (QA–MBS1–SNP) coating enhanced surface hydrophobicity (CA = 90°) without compromising photokilling efficiency. The antibacterial efficacy of these coatings was rigorously tested against the Gram-negative bacterium
Escherichia coli
. The synergistic action of MB and QA demonstrated exceptional photokilling performance achieving >99.999% (>5-log reduction) bactericidal activity under white light (∼500 lux, ∼0.0732 mW cm
−2
) and effectively inhibited biofilm formation by up to 80%. The demonstrated efficacy of these coatings highlights their potential for transformative applications in healthcare settings, providing a robust, multifaceted approach to infection control.

Thermal and surface properties of LiFePO4/very-few-layer graphene (LiFePO4/VFLG) composite manufactured through the sol-gel route have been researched for lithium-ion battery cathode application. VFLG was acquired from a facile, cost-effective, and environmentally benign fluid dynamic shear exfoliation process. The composites were characterized through thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), field-emission scanning electron microscopy (FESEM) interlinked with energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and Braneur-Emmett-Teller (BET) analysis. The TGA-DSC results showed that the integration of VFLG could enhance the thermal stability of the composite by inhibiting oxygen diffusion on the LiFePO4 surface. FESEM-EDX analysis, meanwhile, confirmed the homogeneously distributed VFLG in the composites. TEM results revealed that the average particle sizes of the composites decreased by about 21.2% compared to the bare LiFePO4. TEM and HRTEM results confirmed an intimate contact between VFLG intimately and LiFePO4 particles via plane-to-point contact, contributing to the control and reduction of particle size. Furthermore, physisorption via BET analysis revealed that incorporating VFLG provided a wider distribution of mesopores and increased pore diameter and pore volume by 128.7% and 656.3%, respectively, compared to sole LiFePO4. These significant improvements were related to the flexibility and ability of a thin layer of VFLG to limit the growth of LiFePO4 particles. This approach offers a promising strategy to enhance the thermal stability and surface properties of lithium-ion battery cathodes.

In this study, novel iron-based spiky microparticles (approximately 1-2 mu m in diameter) were synthesized using iron oxalate precursors using a straightforward one-step hydrothermal reaction. The microparticles' morphological, mineralogical and chemical properties were investigated using scanning electron microscopy (SEM), X-ray diffractometry (XRD), Raman spectroscopy and UV-Vis spectroscopy. The physico-chemical characteristics of spiky microparticles were also compared with cubic iron microparticles synthesized using standalone iron as well as with the addition of glycine. XRD and Raman analyses identified substantial presence of humboldtine, a type of ferrous oxalate dehydrate mineral, in the resultant yellowish solid hydrothermal product. The mechanism involving reactions of species in the hydrothermal process was described herein. The results described in this study afford vital insights into the design of iron oxalate-based microparticles synthesis processes.

LiFePO4/Very-few-layer-graphene (LFP/VFLG) composites have been prepared using the sol-gel method for lithium-ion battery cathode. VFLG dominated by 1∼3 layers was obtained from an economical and environmentally benign process. Structural properties of LFP/VFLG composites were studied using Fourier-transform infrared spectra (FTIR) spectroscopy, X-ray diffractometry (XRD), high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy, while the electrochemical performance was measured using galvanostatic discharge, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests. The FTIR analysis confirmed that incorporating VFLG neither affected the chemical structure of LiFePO4 nor initiated any side reactions during the LiFePO4 formation reaction. The XRD results showed that LFP/VFLG composites had better lattice parameters, crystallinity, and phase purity than LiFePO4 without VFLG addition. The Raman spectroscopy analysis indicated that LFP/VFLG composites had a lower disorder in the carbon arrangement. HRTEM results indicated that a VFLG was successfully wrapped around the LFP particle offers a versatile way to enhanced electrochemical performance of LFP/VFLG composites. The galvanostatic discharge profiles showed an enhancing specific discharge capacity of up to 58.3% after incorporating VFLG. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests revealed that LFP/VFLG delivered small polarization, low inner resistance, high electrochemical reaction reversibility, and high lithium-ion diffusion coefficient. VFLG is a promising additive to improve the structural and electrochemical properties of the LiFePO4 cathode of lithium-ion batteries.

CeO2 films with five different oxygen flow ratios, namely 1179°C, 1180°C, 1181°C, 1182°C, 1183°C and 1184°C were synthesized on glass substrates via closed field unbalanced magnetron sputtering technique. These films were characterized using many techniques such as X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FE-SEM), and UV-Vis-NIR. When the post-annealing temperature (TPA) for the films was increased from 1179°C to 1183 °C, a reduction of oxygen in the film was observed, which led to a phase transition from cubic to hexagonal Ce2O3 (002). The phase transition is related to Ce4 to Ce3 transformation due to the formation of oxygen vacancies. XRD studies revealed that all samples have a cubic fluorite CeO2 structure (space group: Fm3m) with a preferred orientation along (1 1 1) except for 1179 °C and 1181°C which prefer (2 2 0) plane orientation. Sample 1179°C showed the highest roughness (3.72nm) while sample 1184 °C has the lowest roughness (1.72nm). Sample 1181 °C showed highest percentage transmittance (>50%) while the other samples showed a percentage transmittance lower than 50%. Most of the films obtained exhibits a smooth and crack free surfaces.

Agroforestry, as a phytoremediation measure, shows great potential for mitigating land degradation by constructing multidimensional and efficient agroforestry composite systems through regulating the microenvironment of agroforestry sites and improving soil properties. However, the effects of different agroforestry composite management modes on saline soils and the interactions between soil–plant systems under salt stress conditions in coastal areas remain largely unexplored. In this study, two salt-tolerant tree species (Sapium sebiferum (Linn.) Roxb and Zelkova serrata (Thunb.) Makino) and four crop species (Medicago sativa, Sesbania cannabina, Sorghum bicolour, and Avena sativa) were selected for intercropping in eight composite patterns via field experiments, with dynamics of soil physicochemical properties and crop photosynthesis observed. The results showed that treatments intercropped with M. sativa had the highest soil bulk density range (1.41–1.48 g cm−3). The dynamics of topsoil (0–10 cm) chemical properties showed similar change patterns among treatments, whereas those of the 10–40 cm soil chemical properties (especially soil pH, soil organic matter [SOM], and total nitrogen [TN]) showed heterogeneity. Moreover, planting S. sebiferum (L.) Roxb under the same crop conditions increased tree height growth rate and survival rate by 75%–114% and 14%–33%, respectively, relative to planting Z. serrata (T.) Makino. Furthermore, a significant negative correlation was observed between soil moisture with crop intercellular CO2 concentration (λ = −0.77), while significant positive correlations were found between crop net photosynthetic rate (Pn) with soil TN (λ = 0.71), as well as SOM with atmospheric CO2 content (λ = 0.72). Structural equation modeling showed significant direct effects between tree height growth rate with soil TN and SOM. Soil moisture (λ = 0.47) and tree height growth rate (λ = 0.53) were dominant drivers of crop Pn. Our findings provide useful information for the prevention of coastal saline soil degradation and sustainable development of agroforestry.

The tribological behaviour of non- and carburised mild steel under oil lubrication was investigated. 2 types of carburised steel specimens were used in this study. The surface of the first type of the carburised steel was rich in retained austenite. Towards the core, the amount of austenite reduced and the amount of martensite increased. In contrast, the surface and subsurface of the second type carburised steel was rich in martensite. In the sliding tests carried out under hydrodynamic lubrication, the COF was found to reduce with increased load before boundary lubrication occurred at loads above 150 N. Under boundary lubrication at 1000 N, the martensite in the carburised layer reacted with the hydrocarbon and oil additive to form a lubricant film consisting of C-C, C=O, C-P, and C-O. This resulted in reduced COF and wear rate, if catastrophic fracture did not take place. The average COF and wear rate obtained at this load was 0.085–0.096 and 1.69–0.94 × 10−11 mm3/Nm, respectively, lower than those that obtained at 600 N which were 0.108–0.109 and 2.89–4.86 × 10−11 mm3/Nm, respectively. The lubricant film formed on the retained austenite, which involved only limited reaction with the hydrocarbon to form C-C, C=O, did not produce any such beneficial effect. These results showed that the presence of the retained austenite made the worn surface less favourable to form an effective anti-wear lubricant film.