Sheet-like Morphology Research Articles

The effect of thermal shock-based heat-treatment on the cost-effective and low-temperature synthesis of needle-like r-BN

While a variety of techniques have been applied to prepare h-BN powders of different morphology, only a few r-BN synthesis methods are presented. In this study, the h-BN structures have been synthesized through controlled nitridation at temperatures lower than 950 ℃. First, a precursor was prepared at 65 ℃ from boric acid and urea, making huge bubbles of B-N-C and flattened at higher temperatures. However, r-BN hollow needle-shaped structures were formed from these h-BN nanosheets by thermal shock-based heat treatment, where the flattening process stopped and sheets rolled. The as-synthesized samples were analyzed by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), simultaneous thermal analysis (STA: thermogravimetric (TGA), and differential thermal analysis (DTA)), transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET) techniques. The h-BN nanosheets are about 500 nm thick, while needle-type structures are approximately 0.88–17 µm long. The specific surface area of mesoporous nanosheets and needle-like hollow r-BN mesoporous structures is 358 and 75 m2/g, respectively. In this research, h-BN and r-BN are synthesized in sheet-like and needle-like morphologies, respectively.

Synthesis of malonic acid-VTiO2 photocatalysts for the photodegradation of micropollutant

Herein, a novel malonic acid-vanadium doped TiO2 (m-VTiO2) photocatalysts with different V ratios were synthesized via crosslinking and hydrothermal treatment. Malonic acid was employed as the cross-linking agent to chemically bind TiO2 and vanadium via its dicarboxylic functional group. The synthesized m-VTiO2 photocatalyst presents a large surface area with sheet-like morphology. XPS results revealed the existence of vanadium in the V5+ and V4+ states, and the binding energies of Ti-O bonds were changed significantly with the introduction of vanadium. The photocatalytic activity increased gradually with the vanadium content and decreased when it attained the maximum value at 7.5% m-VTiO2 for sulfamethoxazole (SMX). The optimal photocatalyst (m-TV3) presents the best photocatalytic activity for SMX owing to its improved surface area. The reaction rate of 7.5 % m-VTiO2 was 4.86-fold higher than that of the un-doped TiO2 particle under visible irradiation. The photodegradation efficiency of SMX was still up to 86.07 % after six cycling runs, indicating the good reusability of the photocatalyst. More importantly, the photocatalysts also show high photocatalytic activity for RHB dye. In addition, a potential mechanism for enhancing the photocatalytic activity under visible irradiation was put forth.

Study the effect of ZnO additive in rGO/ZnO nanocomposites for the investigation of ammonia sensing characteristics

This study reports the synthesis and gas-sensing properties of reduced graphene oxide (rGO), zinc oxide nanoparticles (ZnO NPs), and their nanocomposites (rGO/ZnO NCs). ZnO NPs, rGO, and rGO/ZnO NCs were synthesized using the co-precipitation, modified Hummers method, and the ultrasonic-assisted technique, respectively. The XRD diffraction patterns confirmed the presence of graphitic lattice planes in rGO and the formation of hexagonal ZnO NPs. SEM micrographs revealed the wrinkled sheet-like morphology of rGO and the distribution of ZnO NPs over the rGO surface. The UV–Vis spectroscopy indicated the rGO and ZnO NPs peaks in NC spectrum. FTIR spectroscopy analysis showed the purity of synthesized specimens. Among the samples, ZnO NPs and rGO/ZnO (70/30) NC-based sensors exhibited the best capacitive and resistive response within the 2.5–36 ppm range at 100 Hz, with the later showing quick response/recovery time of 12 s/20 s at 36 ppm. The fabricated sensors also displayed long-term stability and excellent selectivity.

Zinc and Silver-Infused Calcium Silicate Cement: Unveiling Physicochemical Properties and In Vitro Biocompatibility.

Calcium silicate-based types of cement have gained recognition in various dental applications due to their exceptional sealing capabilities, bioactivity, and minimal adaptability. However, these materials have certain shortcomings that can lead to mechanical failures and premature degradation. The inclusion of metal ions into their structure is expected to promote their biological activity. This article focuses on the preparation and characterization of calcium silicate cement to enhance its fundamental material properties, by introducing zinc and silver while retaining its biomaterial characteristics. This study aims to evaluate the biomedical potential of zinc and silver-impregnated bioactive calcium silicate cement. The calcium silicate powder was synthesized via the sol-gel method. Tetraethyl orthosilicate, calcium nitrate, silver nitrate, and zinc nitrate were sequentially added to create the bioactive calcium silicate material. The synthesized particles underwent physicochemical characterization using techniques such as scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and biological characterization through in vitro hemocompatibility assays. The study's results revealed the presence of multiple crystalline phases (Ag6Si2O7, Zn2SiO4, CaCO3) as indicated by X-ray diffraction. Raman spectra displayed vibrations associated with Si-O-Si and Zn-O bonding in the zinc and silver-infused bioactive calcium silicate. Scanning electron microscopy confirmed a mixture of spherical and sheet-like morphologies, while energy dispersive spectra confirmed the presence of elements Ca, Si, Zn, Ag, O, and C. In vitro hemocompatibility testing affirmed the material's biocompatible nature. In conclusion, the zinc and silver-infused calcium silicate cement was successfully synthesized through an in-house procedure and demonstrated biocompatibility. The inclusion of zinc and silver, known for their osteogenic and antimicrobial properties, is anticipated to enhance the cement's biological properties and broaden its utility in dentistry. Further in vitro and in vivo investigations are imperative to validate its clinical applications and elucidate the molecular mechanisms underlying its efficacy.

Enhancing rural drinking water safety using an Mg–Al-type layered double hydroxide foil as a new point-of-use disinfection tool

Abstract Point-of-use (POU) drinking water treatment is crucial for residents in resource-constrained areas. This study introduces a layered double hydroxide (LDH) foil, an innovative POU device that eliminates waterborne pathogens via adsorption. It is an aluminum foil coated with magnesium–aluminum (Mg–Al)-type LDH, a recognized human-safe pathogen adsorbent. Its sheet-like morphology enables easy retrieval of inherently powdered LDH from post-disinfected water. Coating with Mg–Al LDH foils was accomplished by immersing aluminum foils in alkaline magnesium solutions, resulting in the on-surface formation of LDH. Using 12 distinct alkaline magnesium solutions, 12 types of LDH foils were prepared. Most LDH foils demonstrated >99% removal of Escherichia coli (DH5α strain) within 3–24 h when 100 mL of water was inoculated with DH5α at approximately 103 colony-forming units (CFU)/mL agitated with a 25-cm2 LDH foil piece. The LDH foil with the highest efficacy had a maximum adsorption capacity of approximately 1.3 × 106 CFU per 1-cm2 LDH foil. Furthermore, the LDH foil was regenerated by submersing it in the alkaline solution during its preparation, enabling multiple reuses. Owing to its straightforward production and application, the LDH foil holds substantial promise as a convenient-to-use adsorbent for batch water disinfection, such as jug water, in rural households.

Response surface methodology based modelling and optimisation of anionic dyes adsorption onto nitrate intercalated Zn2Al layer double hydroxide adsorbent

ABSTRACT In the present work, nitrate intercalated zinc aluminium layer double hydroxide (ZA-LDH) nanoparticles in the hydrodynamic particle size range between 210 and 530 nm were synthesised using co-precipitation method under reflux condition and nitrogen atmosphere. The pristine ZA-LDH nanoadsorbent was characterised using X-ray diffraction (XRD), Fourier transformation spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM). The results revealed the formation of single-phase ZA-LDH nanopowder with sheet-like morphology. The optimisation of adsorption kinetic parameters with the fixed dose of 10 mg for 50 ml of 0.03 mg/ml MO and AY dye solution was performed using the Box Behnken design model (BBD). The effects of three independent variables such as incubation time, temperature and pH of the suspended ZA-LDH nanoadsorbents in the MO and AY dye solution on the adsorption kinetics were studied. Optimum values for the maximum adsorption capacity were evaluated that included the incubation time of 52.4 min, the temperature of 35.45 ± 0.55°C, and the pH of 5.75 ± 0.75. According to the BBD model, ZA-LDH nanoadsorbent exhibited the maximum adsorption percentage of 99.84% and 99.99% of corresponding MO and AY dye, respectively. The ZA-LDH adsorbent retained up to 72.3% for the MO and 60.43% for the AY dye of regeneration capacity after 5 cycles of regeneration. The adsorption kinetic and isotherm of the MO and AY dyes onto the ZA-LDH nanoadsorbent were well fitted with pseudo second order kinetic model and Langmuir model, respectively. According to Langmuir isotherm, the maximum adsorption capacities of 601.62 mg/g for the MO dye and 462.48 mg/g for the AY dye onto the ZA-LDH were found and those confirmed the monolayer chemisorption mechanism in this case.

Synthesis of 1D/2D VO2 (B) nanowire/g-C3N4 hybrid architectures as cathode materials for high-performance Li-ion batteries

Owing to energy density, powder density, and eco-friendliness, Li-ion batteries (LIBs) are increasingly used in transportable electronic devices and electric vehicles. Monoclinic VO2 (B) has been broadly used as a cathode owing to its abundance, affordability, high capacity, and multiple oxidation states, but it's low repeatability and slow kinetics have restricted its practical applications. To mitigate these shortcomings, novel 1D/2D VO2 (B) nanowire/g-C3N4 hybrid architecture cathode materials were synthesized via hydrothermal method, and its electrochemical activity (i.e., repeatability constancy and rate capability) for LIBs was investigated. X-ray diffraction experiments confirmed that VO2 (B) exhibited a monoclinic crystal phase. SEM images revealed that the g-C3N4 and VO2 (B) presented sheet-like morphologies and comprised nanowires of uniform thickness, respectively. Electrochemical experiments revealed that the hybrid architectures showed a capacity of 779 mAh/g, and VO2 (601.4 mAh/g) and g-C3N4 (340.6 mAh/g) at 0.1 C current density. The remarkable electrochemical activity of the materials was attributed to their distinctive structures, excellent electronic conductivity associated with g-C3N4 sheets, small transport distances for Li+ ions, and fast charge transmission owing to the presence of VO2 (B) nanowires attached to g-C3N4 sheets. Consequently, distinct VO2 (B) nanowire/g-C3N4 hybrid architectures delivered suitable electrode performance to facilitate the design of high-power LIBs and these hybrid composites can serve as suitable cathode materials for rechargeable LIBs.

Silicon infused Molybedenum di-selinide (MoSe2) nanosheets for enhanced hydrogen evolution reaction (HER) and lithium-ion battery (LIB) applications

The systematized design of two-dimensional (2D) nanocatalysts for sensible energy-efficient reactions is quite a puzzling prospective aspect in energy-related applications. In this current work, we used a top-down strategy to synthesize silicon (Si) nanoparticles using a high-energy mechanical ball milling technique. In hydrothermal reaction, these Si nanoparticles were introduced into the 2D MoSe2 matrix sequence based on varying the percentages of silicon (0–15%) vs Selinium content. The high crystalline phases of the synthesized 10% Si:MoSe2 exhibited the sheet-like morphology and silicon inserted layered structure. The pristine MoSe2@CC & Si:MoSe2@CC electrodes were prepared by tape casting method. During HER reaction, the miniscule insertion of Si into MoSe2 matrix amplified the current density until 10% addition and moved the reduction curves towards lower onset overpotential (76.23 mV) in addition to the significant Tafel value (112.3 mV/decade). The potential of the better performed electrode in HER was explored as an anode for Lithium-ion battery (LIB) applications. The electrode delivered a discharge capacity of 406.7 mAh g−1 at a current density of 100 mA/g after 100 charge-discharge cycles. Furthermore, the rationally constructed bifunctional electrode (Si:MoSe2@CC) showed strong physicochemical stability, which can be used in future sustainable energy generation and storage devices.

Sheet-like g-C3N4 for enhanced photocatalytic degradation of naproxen

The development of efficient, stable photocatalysts that exhibit a high response to a broad spectrum of light is a major challenge in the field of photocatalysis. In this work, Bulk and sheet-like morphologies of graphitic carbon nitride (g-C3N4) were synthesised through a thermal polymerization and thermal exfoliation processes, respectively. The materials were characterized with SEM/EDS, XRD, BET, UV–vis DRS, and FTIR. The photocatalytic efficiency for these materials was further studied by photocatalytic degradation of Naproxen (NPX). The sheet-like g-C3N4 (SCN) exhibits superior photodegradation performance for NPX (77.3 % in only 5 min, and reached 98 % in 30 min) with an apparent rate constant ‘k’ (0.31 ± 0.02 min−1), which is about 3 times higher than that of bulk g-C3N4 (0.116 ± 0.003 min−1). The improved photocatalytic performance is attributed to the higher surface area and the appearance of N vacancies, which mitigate photoinduced electron-hole recombination, leading to the generation of more active species. The photocatalytic efficiency using different irradiation sources (natural and simulated sunlight, and UVA radiation at 365 nm) was investigated. Finally, reusability tests of SCN demonstrate an outstanding stability (four cycles) and an excellent photocatalytic performance, which further highlights its potential as a promising photocatalyst for environmental remediation applications.

Superior photocatalytic performance of Dy2O3/graphitic carbon nitride nanohybrid for the oxidation Rhodamine B dye under visible light irradiation: A superoxide free radicals approach

Organic-inorganic hybrid semiconductor nanomaterials have emerged as promising candidates for next-generation energy and environmental solutions. These materials combine organic and inorganic components to form a new class of hybrid nanomaterials with enhanced photocatalytic activity under visible-light irradiation. In this study, g-C3N4 was integrated with different ratios of Dy2O3 using a hydrothermal process. The prepared hybrid composite materials were analysed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), UV–vis diffuse reflectance spectroscopy (UV-DRS), Brunauer-Emmett-Teller (BET) surface area analysis, field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray analysis (EDAX) high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Photoluminescence Spectroscopy (PL) and Electron Paramagnetic Resonance spectroscopy (EPR). The synthesized Dy2O3/g-C3N4 (DYCN) nanohybrid composite has a bandgap energy and surface area of 2.63 eV and 51.8 m2/g respectively. FE-SEM analysis showed nanorods connected to the sheet-like morphology of the prepared DYCN nanohybrid composite material. When exposed to visible light, the organic dye rhodamine B was used as a model pollutant to assess the photocatalytic activity of the synthesized materials. The oxidation of organic molecules was initiated by superoxide (•O2−) free radicals rather than hydroxyl radicals generated during the reaction, which was confirmed by EPR analysis. Due to its narrow bandgap, larger surface area, and presence of f shells in Dy2O3, the synthesized 5 % Dy2O3/g-C3N4 (DYCN 5) nanohybrid composite material showed more visible-light photocatalytic activity than pure g-C3N4 and various ratios of synthesized nanomaterials.

MOF-derived spinel NiMn2O4/CoMn2O4 heterojunction and its application in a high-performance photocatalyst and supercapacitor

Metal oxide heterojunctions have attracted considerable attention in photocatalyst and supercapacitor applications. In this study, NiMn2O4/CoMn2O4 (NMO/CMO) heterojunctions were synthesized using ternary metal-organic frameworks (MOFs) as precursors. After calcination at 500 °C, the as-prepared NMO/CMO composite maintains the porous sheet-like morphology of the ternary MOF, exhibiting a highly porous structure. The heterostructured NMO/CMO composite demonstrates enhanced photocatalytic performance compared with pure NMO and CMO. This enhancement may be attributed to the well-aligned energy levels at the NMO/CMO interface, which effectively reduces charge recombination and facilitates the efficient transport of photogenerated carriers. In addition, the NMO/CMO heterojunction exhibits enhanced supercapacitor performance owing to the increased number of active redox sites and reduced charge transfer resistance. When tested at 3 A/g, the NMO/CMO composite displays a higher capacitance (756.4 F/g) than pure NMO (579.6 F/g) and CMO (519.6 F/g) and remarkable rate capability, maintaining a capacitance of 639 F/g even at 10 A/g. Notably, asymmetric supercapacitors fabricated using NMO/CMO and activated carbon can achieve an energy density of 32.18 W h/kg at 750 W/kg and superior cycling life, retaining 92.1% of its initial capacitance after 3000 cycles.

Topochemically prepared tungsten disulfide nanostructures as a novel pseudocapacitive electrode for high performance supercapacitor

The topochemical preparation of nanostructured materials (NMs) has received significant attention in recent years due to the exceptional electrochemical properties exhibited by the resulting NMs. This work focuses on the preparation of two-dimensional tungsten di-sulfide (WS2) nanostructures through the topochemical conversion of tungsten trioxide (WO3) nanostructures and also evaluates their potential applications as electrode materials for supercapacitors (SCs). The X-ray diffraction and photoelectron studies conducted in this research reveal the conversion of hexagonal WO3 into hexagonal WS2 nanosheets, accompanied by changes in oxidation states. The FE-SEM and HR-TEM studies confirm the formation of WS2 in the sheet-like morphologies with lateral dimensions of 100 × 100 nm. The electrochemical investigation, using techniques such as CV, galvanostatic CD, and EIS, confirmed the presence of intercalation pseudocapacitance in the WS2 electrode, with a higher electrode-specific-capacitance (260 F g−1) than that of WO3 electrode. The WS2 symmetric SC delivered high device capacitance (59.17 F g−1), energy density (8.21 Wh kg−1) and power density (3,750 W kg−1) with better cyclic stability over 5000 cycles. These experimental findings show that the topochemically synthesized WS2as novel supercapacitor electrodes might be useful for the advancement of future-generation energy storage devices.

Femtosecond laser irradiation as a novel method for nanosheet growth and defect generation in g-C3N4

Among the many recently developed photo-catalytic materials, graphitic carbon nitride (g-C3N4) shows great promise as a catalytic material for water splitting, hydrogen generation, and related catalytic applications. Herein, synthesized bulk g-C3N4 is simply irradiated under a 35 fs pulse at mixed photon energies (800 nm and its second harmonic). g-C3N4 was synthesized from melamine following a facile thermal polymerization procedure. The prepared material was introduced, in an aqueous environment, to the femtosecond laser for various lengths of time. The treated material demonstrates a significant increase in surface area, relative to the untreated samples, indicating that irradiation is a successful method for exfoliation. The subsequent characterization reveals that the mixed irradiation process drives significant defect generation and sheet growth, which is not seen under 800 nm irradiation. Extended mixed irradiation results in 4 nm thick nanosheets with lateral dimensions 4× that of the bulk material. The treated material shows improved dye absorption/removal. This novel method of defect generation and nanosheet growth shows great potential as a g-C3N4 pre-treatment method for co-catalytic applications. Herein it is shown that femtosecond laser irradiation drives exfoliation beyond 100 nm particle sizes, and sheet-like morphologies under extended irradiation, which must be taken into account when using this method to improve material performance.

Facile synthesis of Ni0.5Zn0.5Fe2O4/MXene composite powders for high-performance asymmetric supercapacitors

Ni0.5Zn0.5Fe2O4/Ti3C2Tx MXene composite powders were prepared by solution combustion synthesis method. The various amounts of Ti3C2Tx MXene sheets were dispersed in the precursor solution containing the metal nitrates as oxidant and glycine as fuel in water solvent. The effects of Ti3C2Tx MXene contents (25, 50, 75 wt%) on the structural, microstructural, and electrochemical properties were studied by various characterization methods. The Ni0.5Zn0.5Fe2O4 particles covered the Ti3C2Tx MXene sheets at the lower contents. However, the Ti3C2Tx MXene was delaminated to the rutile and anatase TiO2 phases without losing the sheetlike morphology at its higher contents. The Ni0.5Zn0.5Fe2O4 and Ti3C2Tx MXene had the specific capacity of 598 and 680C g−1, respectively, which was enhanced to 1614C g−1 at 1 Ag−1 for the Ni0.5Zn0.5Fe2O4–25 wt%Ti3C2Tx MXene. The hybrid capacitor made of the Ni0.5Zn0.5Fe2O4–25 wt% MXene composite powders as positive electrode and activated carbon as negative electrode showed the energy density of 53 Whkg−1 at the power density of 1335 Wkg−1 by applying a current density of 1 Ag−1.

One-pot citric acid/nitrates combustion design of 2D nanosheet mesoporous BiαClβOδ nanostructure: Efficient sunlight photocatalytic elimination of tetracycline-HCl

The development of high-efficiency and stable nano-photocatalysts for environmental pollution control is a rapidly evolving research domain. The fabrication of Z-scheme heterojunctions with exceptional redox abilities has emerged as a promising and effective approach. In this study, the Z-scheme heterojunction sheet-like photocatalyst was created using a one-pot citric acid/nitrates combustion method, consisting of BiαClβOδ. To optimize the photocatalyst's physicochemical properties, the synthesis process was conducted at different fuel to oxidizer ratios (Φ = 0.25, 0.5, 0.75, 1), which is a critical factor in the combustion reaction. Compared to the pristine BiOCl with a photocatalytic efficiency of 65%, heterojunction nanosheets with a Φ ratio of 0.5 exhibited superior performance in completely removing aqueous tetracycline-HCl under simulated solar light irradiation. This boosting performance is mainly due to the improved light harvesting (Eg = 2.52 eV), charge separation and transfer resulting from the Z-scheme structure, as well as the increased pore volume (0.565 cm3/g) and specific surface area (127.9 m2/g) and well-grown sheet-like morphology resulting from the high temperature, heat, and released gases during combustion. These characteristics were confirmed using various analytical techniques, including DRS, XRD, BET-BJH, FESEM, EDX, and TEM. Finally, the stability of the photocatalysts was tested, and a potential photocatalytic reaction mechanism based on a Z-scheme heterojunction was proposed.

Nanoarchitectonics of Metallene Materials for Electrocatalysis.

Controlling the synthesis of metal nanostructures is one approach for catalyst engineering and performance optimization in electrocatalysis. As an emerging class of unconventional electrocatalysts, two-dimensional (2D) metallene electrocatalysts with ultrathin sheet-like morphology have gained ever-growing attention and exhibited superior performance in electrocatalysis owing to their distinctive properties originating from structural anisotropy, rich surface chemistry, and efficient mass diffusion capability. Many significant advances in synthetic methods and electrocatalytic applications for 2D metallenes have been obtained in recent years. Therefore, an in-depth review summarizing the progress in developing 2D metallenes for electrochemical applications is highly needed. Unlike most reported reviews on the 2D metallenes, this review starts by introducing the preparation of 2D metallenes based on the classification of the metals (e.g., noble metals, and non-noble metals) instead of synthetic methods. Some typical strategies for preparing each kind of metal are enumerated in detail. Then, the utilization of 2D metallenes in electrocatalytic applications, especially in the electrocatalytic conversion reactions, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, fuel oxidation reaction, CO2 reduction reaction, and N2 reduction reaction, are comprehensively discussed. Finally, current challenges and opportunities for future research on metallenes in electrochemical energy conversion are proposed.

P04 Leg ulceration in a patient with antisynthetase syndrome

Abstract A 42-year-old woman presented with leg ulceration on a background of antisynthetase syndrome and immunosuppression with rituximab, azathioprine and prednisolone. The initial lesion was an erythematous patch on the lower leg, which increased in size with violaceous changes. The area subsequently broke down to form an ulcer. On examination, she had a 7-cm ulcerating lesion with central necrosis. Clinically, the appearance was suspicious of pyoderma gangrenosum; biopsy demonstrated scarring without features of vasculitis, atypia or malignancy. The ulcer did not show improvement as expected after oral and topical steroid treatment, with new fleshy nodular growth. Repeat biopsy showed angiocentric atypical lymphocytes with positive Epstein–Barr virus (EBV)-encoded RNA (EBER) staining. Further incisional biopsy demonstrated large, atypical B lymphocytes with a diffuse sheet-like morphology and a poorly circumscribed base. Immunohistochemistry was positive for CD79a, CD30, CD20, MUM1, BCL6, and EBER. Overall, the findings were consistent with EBV-positive diffuse large B-cell lymphoma (DLBCL). The main differential diagnosis was EBV-positive mucocutaneous ulcer (MCU), another EBV-associated lymphoproliferative disorder, albeit with an indolent course (Dojcinov SD, Venkataraman G, Raffeld M et al. EBV positive mucocutaneous ulcer—a study of 26 cases associated with various sources of immunosuppression. Am J Surg Pathol 2010; 34:405–17). In this case, the diffuse sheet-like morphology and poorly circumscribed base favoured EBV-positive DLBCL. The lesion fully healed with withdrawal of immunosuppression and treatment with rituximab therapy, and involved field radiotherapy. First described in 2003, EBV-positive DLBCL is a rare, classically aggressive lymphoma initially believed to only occur in patients older than 50 years of age (Oyama T, Ichimura K, Suzuki R et al. Senile EBV+ B-cell lymphoproliferative disorders. Am J Surg Pathol 2003; 27:16–26). Since the revision of the World Health Organization classification in 2016, it is also recognized to present in younger patients, with an associated better prognosis. EBV-positive DLBCL occurs in both nodal and extranodal sites. Therefore, cutaneous presentations must complete staging investigations to rule out skin involvement secondary to a nodal lymphoma. Our patient highlights a rare complication of immunosuppression. We illustrate the relevance of considering rare causes of ulceration in patients with autoimmune conditions and immunosuppression and demonstrate the importance of considering malignancy in a nonhealing ulcer. Multiple biopsies may be needed in ulcers that poorly respond to treatment. While EBV-positive DLBCL and EBV-positive MCU can be difficult to differentiate, it is vital for prognostication.

Unraveling the Enhanced Electrochemical Performances of Nickel Aluminum Sulfide Lattices for Overall Water Splitting and as Counter Electrode Materials for Dye-Sensitized Solar Cells

The development of a high-performance precious metal-free multifunctional electrocatalyst for overall water splitting is a promising sign for future energy research. Here, a new strategy has been followed for the synthesis of novel-structured binary metal chalcogenide electrocatalysts, such as nickel aluminum sulfide (NiAl2S4) or nickel aluminum selenide (NiAl2Se4) spinels. The new chalcogenides, NiAl2S4 or NiAl2Se4, were confirmed by different physicochemical characterizations. Using a 316 stainless steel (SSL) mesh electrode as a three-dimensional conducting substrate, the electrocatalytic overall water splitting reaction was studied. Here, NiAl2S4 spinel outperformed the other metal chalcogenide in terms of electrocatalytic activity and charge transport in the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and overall water splitting in alkaline medium. Moreover, NiAl2S4 spinel provided the finest electrocatalytic efficiencies compared to other benchmark electrocatalysts with minimized overpotentials, such as 47 or 290 mV for HER or OER, respectively, to reach the current density of 20 mA cm–2. In overall water splitting studies, a two-electrode system was formulated to show a very low potential of 1.54 V at a current density of 20 mA cm–2. Further, the prepared NiAl2S4 electrocatalyst-loaded 316 SSL electrode demonstrated excellent durability in HER, OER, and overall water splitting reactions. The obtained Faradaic efficiency was 97%, which is due to the two-dimensional sheet-like morphology of NiAl2S4, enabling a high active surface area for efficient water electrolysis. Furthermore, NiAl2S4 spinel performed well as a counter electrode (CE) material in dye-sensitized solar cells, with an efficiency of 5.02% compared to Pt (5.38%) on the fluorine-doped indium tin oxide electrode.

Extraction, Rheological, and Physicochemical Properties of Water-Soluble Polysaccharides with Antioxidant Capacity from Penthorum chinense Pursh.

This study aimed to isolate polysaccharides from Penthorum chinense Pursh and evaluate their rheological characteristics, physicochemical properties, and antioxidant activity. The optimal conditions for the maximal extraction yield of Penthorum chinense Pursh polysaccharides (4.05 ± 0.12%) were determined by employing a single-factor test and response surface methodology which included an extraction time of 3 h, a liquid-solid ratio of 20 mL/g, and three separate extraction times. The rheological experiments showcased that the P. chinense polysaccharides exhibited typical shear-thinning behavior, with their apparent viscosity being influenced by various parameters such as concentration, pH, temperature, salt content, and freeze-thaw. The purified polysaccharides (PCP-100), having an average molecular weight of 1.46 × 106 Da, mainly consisted of glucose (18.99%), arabinose (22.87%), galactose (26.72%), and galacturonic acid (21.89%). Furthermore, the PCP-100 exhibited high thermal stability and displayed an irregular sheet-like morphology. Its superior reducing power and free radical scavenging ability implied its significant antioxidant activity in vitro. Collectively, these findings provide important insights for the future application of P. chinense polysaccharides in the food industry.

NiOX Template-Grown Ni-MOF-Coated Carbon Paper Electrode Embedded Extended Gate Field Effect Transistor for Glucose Detection in Saliva: En Route toward the Noninvasive Diagnosis of Diabetes Mellitus

Our present work focuses on the development of nickel oxalate (NiOX) template-assisted growth of a nickel–metal organic framework (Ni-MOF) with sheetlike morphology on carbon paper (CP) electrode for the noninvasive detection of glucose. We have utilized an extended gate field effect transistor (EGFET) where the Ni-MOF/CP electrode serves as the extended gate of a commercial n-type metal oxide semiconductor FET for sensing glucose. The electrode detects glucose concentrations ranging from 20 μM to 1.47 mM. The sensor operates at a voltage of 0.7 V in the physiologically relevant electrolyte of phosphate-buffered saline (PBS) with a response time of less than 5 s. The sensitivity is calculated as 86 μA mM–1 cm–2 from the linear region of the sensor response to the glucose concentration (20 μM to 0.27 mM). Also, Ni-MOF/CP has shown a good selective response toward glucose against uric acid, sucrose, fructose, and ascorbic acid. Additionally, the glucose sensing mechanism is investigated through work function changes of the sensing electrode using a scanning Kelvin probe. Real-time sample testing has revealed that the sensor preserves the sensitivity in human saliva too. In summary, we conclude that the Ni-MOF/CP extended gate electrode EGFET is an alternative device for salivary glucose detection toward the noninvasive diagnosis of diabetes mellitus that can identify hyperglycemic, normal, and hypoglycemic conditions.