Titanium Silicide: A Promising Candidate of Recombination Layer for Perovskite/Tunnel Oxide Passivated Contact Silicon Two-Terminal Tandem Solar Cells.

This study proposes a titanium silicide (TiSi2) recombination layer for perovskite/tunnel oxide passivated contact (TOPCon) 2-T tandem solar cells as an alternative to conventional transparent conductive oxide (TCO)-based recombination layers. TiSi2 was formed while TiO2 was made by oxidizing a Ti film deposited on the p+-Si layer. The reaction formation mechanism was proposed based on the diffusion theory supported by experimental results. The optical and electrical properties of the TiSi2 layer were optimized by controlling the initial Ti thicknesses (5-100 nm). With the initial Ti of 50 nm, the lowest reflectance and highly ohmic contact between the TiO2 and p+-Si layers with a contact resistivity of 161.48 mΩ·cm2 were obtained. In contrast, the TCO interlayer shows Schottky behavior with much higher contact resistivities. As the recombination layer of TiSi2 and the electron transport layer of TiO2 are formed simultaneously, the process steps become simpler. Finally, the MAPbI3/TOPCon tandem device yielded an efficiency of 16.23%, marking the first reported efficiency for a device including a silicide-based interlayer.

Radiation induces acute and subacute vascular regression in a three-dimensional microvasculature model.

Radiation treatment is one of the most frequently used therapies in patients with cancer, employed in approximately half of all patients. However, the use of radiation therapy is limited by acute or chronic adverse effects and the failure to consider the tumor microenvironment. Blood vessels substantially contribute to radiation responses in both normal and tumor tissues. The present study employed a three-dimensional (3D) microvasculature-on-a-chip that mimics physiological blood vessels to determine the effect of radiation on blood vessels. This model represents radiation-induced pathophysiological effects on blood vessels in terms of cellular damage and structural and functional changes. DNA double-strand breaks (DSBs), apoptosis, and cell viability indicate cellular damage. Radiation-induced damage leads to a reduction in vascular structures, such as vascular area, branch length, branch number, junction number, and branch diameter; this phenomenon occurs in the mature vascular network and during neovascularization. Additionally, vasculature regression was demonstrated by staining the basement membrane and microfilaments. Radiation exposure could increase the blockage and permeability of the vascular network, indicating that radiation alters the function of blood vessels. Radiation suppressed blood vessel recovery and induced a loss of angiogenic ability, resulting in a network of irradiated vessels that failed to recover, deteriorating gradually. These findings demonstrate that this model is valuable for assessing radiation-induced vascular dysfunction and acute and chronic effects and can potentially improve radiotherapy efficiency.

Quantitative Analysis of RNA Polymerase Slippages for Production of P3N-PIPO Trans-frame Fusion Proteins in Potyvirids.

Potyvirids, members of the family Potyviridae, produce the P3N-PIPO protein, which is crucial for the cell-to-cell transport of viral genomic RNAs. The production of P3N-PIPO requires an adenine (A) insertion caused by RNA polymerase slippage at a conserved GAAAAAA (GA6) sequence preceding the PIPO open reading frame. Presently, the slippage rate of RNA polymerase has been estimated in only a few potyvirids, ranging from 0.8 to 2.1%. In this study, we analyzed publicly available plant RNA-seq data and identified 19 genome contigs from 13 distinct potyvirids. We further investigated the RNA polymerase slippage rates at the GA6 motif. Our analysis revealed that the frequency of the A insertion variant ranges from 0.53 to 4.07% in 11 potyviruses (genus Potyvirus). For the two macluraviruses (genus Macluravirus), the frequency of the A insertion variant was found to be 0.72% and 10.96% respectively. Notably, the estimated RNA polymerase slippage rates for 12 out of the 13 investigated potyvirids were reported for the first time in this study. Our findings underscore the value of plant RNA-seq data for quantitative analysis of potyvirid genome variants, specifically at the GA6 slippage site, and contribute to a more comprehensive understanding of the RNA polymerase slippage phenomenon in potyvirids.

Thermal, dielectric, mechanical and structural behavior of 2-amino 4-methylpyridinium 4-nitrophenolate 4-nitrophenol bulk single crystal.

Applications in both science and industry have received increased attention as a result of bulk single crystals with particular orientations. However, due to the instability of organic crystals at high temperatures and stress, there is an interest in growing good-quality bulk single crystals with stable thermal and mechanical properties. Here, the 2-amino 4-methylpyridinium 4-nitrophenolate 4-nitrophenol (2A4MPPP) crystal was prepared employing a single-wall ampoule and the vertical Bridgman technique. Structure and functional groups were determined by XRD, NMR, and FTIR studies. More importantly, detailed thermal and kinetic properties such as activation energy, frequency factor, rate constant, and Avrami exponent are discussed. The mechanical stability and dielectric studies are also demonstrated for the title compound. According to the single crystal XRD investigation, 2A4MPPP is a member of the orthorhombic crystal system with the Pna21 space group. Through the TGA and DTA analyses, it was confirmed that the compound starts to melt at 98 °C and complete melting occurs at 103.3 °C. The dielectric experiments reveal the crystal's poor dielectric constant and high-frequency dielectric loss. Vickers microhardness investigations show that grown 2A4MPPP belongs to the soft materials group. As a result of these findings, the 2A4MPPP crystal should be well suited for usage in thermomechanical, microelectronic, optical communications, and nonlinear optical applications.

Sulfur deficiency mediated visible emission of ZnS QDs by magnesium dopant and their application in waste water treatment.

The photocatalyst with antimicrobial activity serves as a better candidate material for wastewater treatment, as wastewater contains microbes, hazardous dyes, and heavy metals. Hence, the present study extensively examines the photocatalytic and antibacterial activities against two waterborne bacterial strains, namely Salmonella typhi and Escherichia coli. Pure and Mg-doped ZnS (Mg:ZnS) quantum dots (QDs) were synthesized using a low-cost and simple co-precipitation method. The QDs' structural, surface morphology, chemical purity, and optical characteristics were analyzed through XRD, SEM, EDAX, TEM, UV-visible, and photoluminescence spectra. The incorporation of Mg dopants did not introduce significant alterations to the cubic blende structure of ZnS, nor did it induce substantial changes in the structural parameters. However, the QDs exhibited a slight sulfur deficiency, which was further increased by the presence of Mg dopant. The Mg dopant, due to its dominant compositional effect, reduced the band gap. Several optical emission bands were observed in the UV, violet, blue, and green regions, corresponding to NBE emission, sulfur-related defects, and Zn-related defects. Initially, Mg doping enhanced visible emission related to defects, while NBE emission was suppressed by the Mg dopant. However, increasing the concentration of the Mg dopant led to a slight increase in NBE emission. The Mg dopant enhanced the photocatalytic activity of the QDs, and a strong correlation was found between photocatalytic activity and NBE emission. The presence of the Mg dopant led to an increased rate of ROS-based decolorization by reducing the electron-hole recombination rate.

Silver-functionalized bismuth oxide (AgBi2O3) nanoparticles for the superior electrochemical detection of glucose, NO2- and H2O2.

In this study, silver-functionalized bismuth oxide (AgBi2O3) nanoparticles (SBO NPs) were successfully synthesized by a highly efficient hydrothermal method. The as-synthesized SBO nanoparticles were characterized using FT-IR, P-XRD, XPS, HR-SEM, and HR-TEM analytical methods. It was found that the NPs were in spherical shape and hexagonal crystal phase. The newly prepared SBO electrode was further utilized for the detection of glucose, NO2- and H2O2 by cyclic voltammetry (CV) and amperometric methods. The electrodes exhibited high sensitivity (2.153 µA mM-1 cm-2 for glucose, 22 µA mM-1 cm-2 for NO2- and 1.72 µA mM-1 cm-2 for H2O2), low LOD (0.87 µM for glucose, 2.8 µM for NO2- and 1.15 µM for H2O2) and quick response time (3 s for glucose, 2 s for both NO2- and H2O2 respectively). The sensor exhibited outstanding selectivity despite the presence of various interferences. The developed sensor exhibited good repeatability, reproducibility, and stability. In addition, the sensor was used to measure glucose, H2O2 in human serum, and NO2- in milk and river water samples, demonstrating its potential for use in the real sample.

Biosynthesis of Co3O4 nanomedicine by using Mollugo oppositifolia L. aqueous leaf extract and its antimicrobial, mosquito larvicidal activities.

Nanotechnology is a relatively revolutionary area that generates day-to-day advancement. It makes a significant impact on our daily life. For example, in parasitology, catalysis and cosmetics, nanoparticles possess distinctive possessions that make it possible for them in a broad range of areas. We utilized Mollugo oppositifolia L. aqueous leaf extract assisted chemical reduction method to synthesize Co3O4 nanoparticles. Biosynthesized Co3O4 Nps were confirmed via UV-Vis spectroscopy, scanning electron microscope, X-ray diffraction, EDX, Fourier-transform infrared, and HR-TEM analysis. The crystallite size from XRD studies revealed around 22.7 nm. The biosynthesized Co3O4 nanoparticle was further assessed for mosquito larvicidal activity against south-urban mosquito larvae Culex quinquefasciatus, and antimicrobial activities. The synthesized Co3O4 particle (2) displayed significant larvicidal activity towards mosquito larvae Culex quinquefasciatus with the LD50 value of 34.96 µg/mL than aqueous plant extract (1) and control Permethrin with the LD50 value of 82.41 and 72.44 µg/mL. When compared to the standard antibacterial treatment, Ciprofloxacin, the Co3O4 nanoparticle (2) produced demonstrates significantly enhanced antibacterial action against the pathogens E. coli and B. cereus. The MIC for Co3O4 nanoparticles 2 against C. albicans was under 1 µg/mL, which was much lower than the MIC for the control drug, clotrimale, which was 2 µg per milliliter. Co3O4 nanoparticles 2, with a MIC of 2 µg/mL, has much higher antifungal activity than clotrimale, whose MIC is 4 µg/mL, against M. audouinii.

Analysis of impacts of exogenous pollutant bisphenol-A penetration on soybeans roots and their biological growth.

Bisphenol A (BPA) is a common chemical used in plastic production. BPA, which has the potential to be poisonous to plants, has lately emerged as a serious environmental concern owing to its extensive usage and release patterns. Prior study has only looked at how BPA affects plants up to a certain stage in their growth. The precise mechanism of toxicity, penetration of BPA, and damage to internal root tissues remains unknown. Therefore, the goal of this study was to examine the hypothesized mechanism for BPA-induced root cells by studying the effects of bisphenol A (BPA) on the ultrastructure and function of root tip cells of soybean plants. We looked at plant changes in root cell tissues after BPA exposure. Further, the biological characteristics that responded to BPA stress were investigated, and the accumulation of BPA in the root, stem, and leaf of the soybean plant was systematically investigated by using FTIR and SEM analysis. The uptake of BPA is a key internal factor that contributes to changes in biological characteristics. Our findings provide insight into how BPA could alter plant root growth, which might contribute new knowledge toward a better scientific appraisal of the possible dangers of BPA exposure for plants.

High-throughput RNA sequencing analysis of Mallotus japonicus revealed novel polerovirus and amalgavirus.

High-throughput RNA sequencing (RNA-seq) analysis of samples from Mallotus japonicus, a traditional medicinal plant, yielded two novel RNA viruses tentatively named Mallotus japonicus virus A (MjVA) and Mallotus japonicus virus B (MjVB). The MjVA and MjVB genomes encode proteins showing amino acid sequence similarities to those of poleroviruses (the genus Polerovirus, the family Solemoviridae) and amalgaviruses (the genus Amalgavirus, the family Amalgaviridae), respectively. The MjVA genome contains seven highly overlapping open reading frames, which are translated to seven proteins through various translational mechanisms, including -1 programmed ribosomal frameshifting (PRF) at the slippery motif GGGAAAC, non-AUG translational initiation, and stop codon readthrough. The MjVB genome encodes two proteins; one of which is translated by +1 PRF mechanism at the slippery motif UUUCGN. The abundance analysis of virus-derived RNA fragments revealed that MjVA is highly concentrated in plant parts with well-developed phloem tissues as previously demonstrated in other poleroviruses, which are transmitted by phloem feeders, such as aphids. MjVB, an amalgavirus generally transmitted by seeds, is distributed in all samples at low concentrations. Thus, this study demonstrates the effectiveness and usefulness of RNA-seq analysis of plant samples for the identification of novel RNA viruses and analysis of their tissue distribution. Keywords: Polerovirus; Amalgavirus; Mallotus japonicus; RNA virus; viral genome; programmed ribosomal frameshifting.

Atomic layer encapsulation of ferrocene into zeolitic imidazolate framework-67 for efficient arsenic removal from aqueous solutions.

Arsenic (As(V))-contaminated water is a major global threat to human health and the ecosystem because of its enormous toxicity, carcinogenicity, and high distribution in water streams. Thus, As(V) removal in the environmental samples has received considerable attention. Till now, numerous metal-organic framework materials have been used for the As(V) removal from the aqueous medium, but low As(V) removal and instability of the adsorbents have severely cut off their practical applications. In this study, a ferrocene-encapsulated zeolitic imidazolate framework-67 (Fc-ZIF-67) material was synthesized for As(V) removal from an aqueous solution at neutral pH using a simple solution mixing process. The ferrocene encapsulation provides water-stable and structural defects to ZIF-67. Furthermore, the ferrocene molecule and imidazole linker can enhance As(V) adsorption via both chemisorption and physisorption. The novel Fc-ZIF-67 adsorbent exhibited superior As(V) adsorption performance with an adsorption capacity of 63.29 mg/g at neutral pH. The Langmuir and Freundlich isotherm models were also used to analyze adsorption behavior.

A novel RNA virus, Thesium chinense closterovirus 1, identified by high-throughput RNA-sequencing of the parasitic plant Thesium chinense.

The genome sequence of a closterovirus (genus Closterovirus, family Closteroviridae), tentatively named Thesium chinense closterovirus 1 (TcCV1), was identified by performing high-throughput RNA-sequencing of the haustoria and root tissues of Thesium chinense, a parasitic plant. The TcCV1 genome was predicted to encode nine proteins, eight of which have orthologs in previously identified closteroviruses. The TcCV1 RNA-dependent RNA polymerase (RdRp) and heat shock protein 70 homolog (Hsp70h) showed 27.8-68.2% and 23.8-55.1% amino acid identity, respectively, to orthologous proteins of known closteroviruses. The putative +1 ribosomal frameshifting site required for producing RdRp was identified as GUUUAGC with UAG stop codon and the skipped nucleotide U. Phylogenetic trees based on RdRp and Hsp70h show that TcCV1 is a novel member of the genus Closterovirus, forming a subclade with a group of known closteroviruses, including mint virus 1 and carnation necrotic fleck virus. The genome sequence of TcCV1 may be useful for studying the genome evolution of closteroviruses. Keywords: Thesium chinense closterovirus 1; Closterovirus; Closteroviridae; Thesium chinense.

Artemisia capillaris nucleorhabdovirus 1, a novel member of the genus Alphanucleorhabdovirus, identified in the Artemisia capillaris transcriptome.

A novel, negative-sense, single-stranded RNA virus, Artemisia capillaris nucleorhabdovirus 1 (AcNRV1), was identified in the transcriptome data of Artemisia capillaris (commonly known as capillary wormwood) root tissue. The AcNRV1 genome contains six open reading frames encoding a nucleocapsid (N), phosphoprotein, movement protein P3, matrix protein, glycoprotein, and polymerase (L). Sequence comparison and phylogenetic analysis using L and N protein sequences revealed that AcNRV1 is a novel member of the genus Alphanucleorhabdovirus, one of the six plant-infecting rhabdovirus genera of the family Rhabdoviridae. Wheat yellow striate virus and rice yellow stunt virus were identified as the closest known rhabdoviruses of AcNRV1. The conserved regulatory sequences involved in transcription termination/polyadenylation (TTP) and transcription initiation (TI) of individual genes were identified in the AcNRV1 genome with the consensus sequence 3'-(A/U)UUAUUUUU-GGG-UUG-5' (in the negative-sense genome), whereby dashes separate the TTP, untranscribed intergenic spacer, and TI elements. The AcNRV1 genome sequence will contribute to further understanding the genome structural evolution of plant rhabdoviruses. Keywords: Artemisia capillaris nucleorhabdovirus 1; plant virus; Alphanucleorhabdovirus; Rhabdoviridae.

Identification of dicistro-like viruses in the transcriptome data of Striga asiatica and other plants.

Dicistroviruses (the family Dicistroviridae) are positive-sense single-stranded RNA viruses of the order Picornavirales, which is a rapidly growing viral group. They have been detected in a wide range of animals, predominantly in insects and crustaceans. In this study, we identified the genome sequences of 14 dicistro-like viruses in the transcriptome data from 12 plant species, including Striga asiatica dicistro-like virus 1 and 2 identified in the transcriptome data of Striga asiatica. Sequence comparison and phylogenetic analysis indicated that these 14 plant-associated dicistro-like viruses were novel members of the family Dicistroviridae, five of which are placed within the genera Aparavirus and Cripavirus, which mainly consist of viruses infecting animals, including insects. The other nine plant dicistro-like viruses formed clades with unclassified dicistroviruses. Our study implies that a wide range of plant species may serve as hosts for dicistroviruses or reservoirs for their transmission. Keywords: dicistrovirus; Dicistroviridae; plant; transcriptome; Striga asiatica.

Effect of Ca2+ ions on naphthalene adsorption/desorption onto calcium oxide nanoparticle: Adsorption isotherm, kinetics and regeneration studies.

The adsorptive nature of calcium oxide nanoparticles in aqueous sample of naphthalene in presence of Ca2+ ions was estimated. Enhanced efficiency of calcium oxide regeneration (90%) with the aid of calcium chloride in the solution concentration of 0.002-0.1 M was depicted. The less degree of toxic naphthalene desorption merged with SEM, FTIR and XRD characterization data portrays the importance of naphthalene adsorption onto calcium oxide using calcium chloride for regeneration. Batch adsorption studies were performed to evaluate the operating parameters such as pH, naphthalene concentration, contact time and impact of Ca2+ on naphthalene study. The adsorption isotherm of naphthalene on calcium oxide nanoparticle was described by Langmuir, Freundlich, Temkin and Dubinin Radushkevich and theoretical maximum monolayer adsorption capacity was found to be 63.81 mg/g at 303 K. The adsorption kinetic best fitted with pseudo second order kinetic model. The positive influence of making the addition of Ca2+ ions into naphthalene solution for its rapid adsorption was elucidated which is leaded by a probable increase in sorption capacity for naphthalene molecules at lower concentrations. The stable nature of crystallinity of calcium oxide and a less degree of naphthalene molecules leaching during consecutive cycles of adsorptive process and nanoparticle regeneration was also scrutinized.

Two novel poty-like viruses identified from the transcriptome data of purple witchweed (Striga hermonthica).

Potyvirids (the family Potyviridae) are the largest family of plant RNA viruses. Two novel potyvirid viruses, Striga-associated poty-like virus 1 (SaPlV1) and Striga-associated poty-like virus 2 (SaPlV2), were identified from the transcriptome data of purple witchweed (Striga hermonthica). SaPlV1 was most closely related to bellflower veinal mottle virus (BVMoV), the only member of the genus Bevemovirus, and then to macluraviruses (the genus Macluravirus). The SaPlV1 genome encodes a 2462-amino acid (aa) polyprotein that may be cleaved into nine mature peptides. The cleavage sites of SaPlV1, BVMoV, and macluravirus polyproteins shared strong sequence similarities. SaPlV2 was most closely related to celery latent virus, the sole species of the genus Celavirus, which is the most divergent potyvirid genus. The SaPlV2 polyprotein contained 3329 aa and it may be cleaved into at least seven or eight mature peptides. Phylogenetic analysis suggested that SaPlV1 and SaPlV2 may be novel species of the genera Bevemovirus and Celavirus, respectively. The genome sequences of SaPlV1 and SaPlV2 are useful resources for studying the genome evolution of potyvirids. Keywords: Striga-associated poty-like virus 1; Striga-associated poty-like virus 2; Potyviridae; Beve- movirus; Celavirus; purple witchweed; Striga hermonthica.

Identification of the genome sequence of Zostera associated varicosavirus 1, a novel negative-sense RNA virus, in the common eelgrass (Zostera marina) transcriptome.

Varicosaviruses (the genus Varicosavirus) are bipartite, negative-sense, single-stranded RNA viruses that infect plants. We analyzed a transcriptome dataset isolated from the common eelgrass (Zostera marina) and identified a novel varicosavirus named Zostera associated varicosavirus 1 (ZaVV1). The ZaVV1 genome consists of two genomic segments: RNA1 (6,632-nt) has an open reading frame (ORF) encoding a large multi-functional polymerase protein (L), while RNA2 (4,304-nt) has four ORFs: one for a nucleocapsid protein and three for proteins with unknown functions (P2, P3, and P4). Sequence comparison and phylogenetic analysis using L proteins showed that ZaVV1 is a novel member of the genus Varicosavirus of the family Rhabdoviridae. The conserved regulatory elements involved in transcription termination/polyadenylation and transcription initiation were identified in the ZaVV1 gene-junction regions with the consensus sequence 3'-UAUUAUUCUUUUUGCUCU-5' (in the negative-sense genome). The ZaVV1 genome sequence may be useful for studying the phylogenetic relationships of varicosaviruses and genome evolution of rhabdoviruses. Keywords: Zostera associated varicosavirus 1; Varicosavirus; Rhabdoviridae; common eelgrass; Zostera marina.

Highly efficient and simultaneous catalytic reduction of multiple toxic dyes and nitrophenols waste water using highly active bimetallic PdO-NiO nanocomposite.

Azo dyes and nitrophenols have been widely used in the various industry which are highly toxic and affecting the photosynthetic cycle of aquatic organism. The industry disposals increase the accumulation of azo compounds in the environment. In the present study, we synthesized the low cost, PdO-doped NiO hetero-mixture via simple hydrothermal combined calcination process. The morphology results proved that, the spherical PdO nanoparticles are evenly doped with NiO nanoparticles. The band gap values of metal oxides NiO, PdO and PdO-NiO composite were found to be 4.05 eV, 3.84 eV and 4.24 eV, respectively. The high optical bandgap (Eg) value for composite suggests that the PdO interface and NiO interface are closely combined in the composite. The catalytic activity of the PdO-NiO was analyzed for the reduction of different toxic azo compounds namely, 4-nitrophenol (NP), 2,4-dinitrophenol (DNP), 2,4,6-trinitrophenol (TNP), methylene blue (MB), rhodamine B (RhB) and methyl orange (MO) separately and their mixture with the presence of a NaBH4. For the first time, the large volume of the toxic azo compounds was reduced into non-toxic compounds with high reduction rate. The proposed PdO-NiO catalyst exhibit excellent rate constant 0.1667, 0.0997, 0.0686 min-1 for NP, DNP and TNT and 0.099, 0.0416 and 0.0896 min-1 for MB, RhB and MO dyes respectively which is higher rate constant than the previously reported catalysts. Mainly, PdO-NiO completes the reduction of mixture of azo compounds within 8 min. Further, PdO-NiO exhibit stable reduction rate of azo compounds over five cycles with no significant loss. Hence, the proposed low cost and high efficient PdO-NiO catalyst could be the promising catalyst for degradation of azo compounds.

Bone Fracture-Treatment Method: Fixing 3D-Printed Polycaprolactone Scaffolds with Hydrogel Type Bone-Derived Extracellular Matrix and ß-Tricalcium Phosphate as an Osteogenic Promoter.

Bone formation and growth are crucial for treating bone fractures. Improving bone-reconstruction methods using autologous bone and synthetic implants can reduce the recovery time. Here, we investigated three treatments using two different materials, a bone-derived decellularized extracellular matrix (bdECM) and ß-tricalcium phosphate (ß-TCP), individually and in combination, as osteogenic promoter between bone and 3D-printed polycaprolactone scaffold (6-mm diameter) in rat calvarial defects (8-mm critical diameter). The materials were tested with a human pre-osteoblast cell line (MG63) to determine the effects of the osteogenic promoter on bone formation in vitro. A polycaprolactone (PCL) scaffold with a porous structure was placed at the center of the in vivo rat calvarial defects. The gap between the defective bone and PCL scaffold was filled with each material. Animals were sacrificed four weeks post-implantation, and skull samples were preserved for analysis. The preserved samples were scanned by micro-computed tomography and analyzed histologically to examine the clinical benefits of the materials. The bdECM-ß-TCP mixture showed faster bone formation and a lower inflammatory response in the rats. Therefore, our results imply that a bdECM-ß-TCP mixture is an ideal osteogenic promoter for treating fractures.

Tetracyanonickelate (II)/KOH/reduced graphene oxide fabricated carbon felt for mediated electron transfer type electrochemical sensor for efficient detection of N2O gas at room temperature.

N2O is the most significant anthropogenic greenhouse gas, which cause the ozone depletion. Hence, the room temperature detection of N2O is highly desirable. In this work, The TCN(II)-KOH-rGO/CF modified electrode was successfully fabricated by drop coating method. The synthesized electrode was successfully characterized by SEM, TEM, FT-IR and XRD. The sensor electrode was used to detect different N2O concentration in flow conditions at room temperature. TCN(II)-KOH-rGO/CF modified electrode showed high sensitivity towards N2O, a wide range from 1ppm to 16 ppm and low detection of 1 ppm N2O were achieved for the TCN(II)-KOH-rGO/CF modified electrode. The limit of detection and the response towards this nitrogen oxide is competitive to other sensing methods. In addition, the sensitivity of the electrochemical sensor electrode was compared with the online Gas Chromatography. Additionally, the selectivity of the working electrode was analyzed and specified. The working electrode stability was analyzed for more than 30 days shows good stability. The fabricated TCN(II)-KOH-rGO/CF electrode is easier to prepare to get excellent analytical performance towards N2O. Hence, the proposed TCN(II)-KOH-rGO/CF electrode could be the suitable material for detection of N2O in the real site process.

Synthesis of porous 2D layered nickel oxide-reduced graphene oxide (NiO-rGO) hybrid composite for the efficient electrochemical detection of epinephrine in biological fluid.

In the present research work, 2D-Porous NiO decorated graphene nanocomposite was synthesized by hydrothermal method to monitored the concentration of epinephrine (EPI). The morphology (SEM and TEM) results confirmed 2D-Porous NiO nanoparticles firmly attached over graphene nanosheets. FTIR and XPS analysis confirmed the formation of nickel oxide formation and complete reduction of GO to rGO. The electrochemical activity of the proposed NiO-rGO/GCE modified electrode on epinephrine was analyzed by simple cyclic voltammetry technique. The proposed low cost NiO-rGO/GCE modified electrode showed excellent catalytic activity over GCE and rGO/GCE electrodes. Due to its high conductivity and charge transfer ability of the NiO-rGO/GCE modified electrode exhibited high sensitivity of EPI at optimized conditions. The anodic peak current of the EPI linearly increases with increasing the concertation of EPI. A wide linear range (50 µM-1000 µM) was achieved with high correlation coefficient (R2 = 0.9986) and the limit of detection (LOD) of NiO-rGO/GCE modified electrode was calculated to be 10 µM. NiO-rGO/GCE electrode showed good stability and repeatability towards the EPI oxidation. Mainly, the proposed NiO-rGO/GCE modified electrode showed good sensitivity of EPI in the human biological fluid with high recovery percentage. The low cost, NiO-rGO/GCE electrode could be the promising sensor electrode for the detection of Epinephrine in the real samples.