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Two-dimensional (2D) materials play a crucial role as fundamental electrical components in modern electronics and optoelectronics next-generation artificial intelligent devices. This study presents a methodology for creating a laterally uniform p–n junction by using a partial oxygen plasma-mediated strategy to introduce p-type doping in single channel MoTe2 device. The MoTe2 field effect transistors (FETs) show high electron mobility of about ∼23.54 cm2 V−1 s−1 and a current ON/OFF ratio of ∼106 while p-type FETs show hole mobility of about ∼9.25 cm2 V−1 s−1 and current ON/OFF ratio ∼105 along with artificially created lateral MoTe2 p–n junction, exhibited a rectification ratio of ∼102 and ideality factor of ∼1.7 which is proximity to ideal-like diode. Thus, our study showed a diversity in the development of low-power nanoelectronics of next-generation integrated circuits.

Environmental remediation of toxic organic pollutants on catalytic degradation has gained much attention. Organic dyes and fossil fuels as pollutants are the two major problems nowadays. The efficient and targeted eradication of organic dye from water systems is a critical global concern for the treatment of both drinking water and wastewater. In this study, ZnO–ZnS–CdO–CdS quaternary core–shell nanocomposites (NCs) were synthesized using Ricinus communis as a stabilizing agent and hydrazine hydrate as a reducing agent. UV-visible spectroscopy and photoluminescence confirmed the formation of NCs. Fourier transform infrared spectroscopy confirmed the presence of functional groups, while scanning electron microscopy analysis revealed that the morphology of nanomaterials was spherical and poly distributed. X-ray powder diffraction confirmed the crystalline nature of prepared samples. The prepared nanocatalysts were used in the production of hydrogen gas from green sources of the Brassica campestris leaf extract and the degradation of Congo red and methyl red dyes. Overall, the photocatalytic performance of NCs and their design was successful. The prepared catalysts were not only active in the degradation of a single substrate but also in the degradation of a mixture of dyes.

In the current study, pure and manganese-doped superparamagnetic iron oxide nanoparticles (Mn-doped SPIONPs) were successfully prepared by a green approach using a fresh aqueous extract of Asparagus officinalis as a reducing and stabilizing agent. Magnetic behaviors of pure and Mn-doped SPIONPs were measured at room temperature against various field strengths by a vibrating sample magnetometer (VSM). The saturation magnetization was in the range of 5.39–2.07 emu. Absorption at 340 nm in the UV-visible spectrum confirmed the presence of iron oxide nanoparticles (IONPs). The presence of plant extract as a capping agent was confirmed by Fourier transform infrared (FTIR) spectroscopy. The crystalline nature of IONPs was confirmed by X-ray diffraction. A gradual increase in size was observed with increasing concentration of Mn. The synthesized materials were applied successfully as sorbent for the effective removal of lead ions (Pb(ii)). Experimental results of adsorption were also analyzed by Langmuir and Freundlich isotherm equations at different temperatures. The results suggested that sorption processes were spontaneous, and the synthesized SPIONPs displayed PbII removal capacity at higher loadings with q m of 21.3 and 29.56 mg·g−1 for undoped and 7% Mn-doped IOPNs, respectively, as compared to the commercial activated carbon.

Palladium is very expensive metal and has numerous applications especially as a versatile hydrogenation and dehydrogenation catalyst for chemical reactions. The main hurdle in its wide use is the high materials cost. In the present study a cost effective palladium nano catalyst was prepared using the green method of synthesis with guar gum as capping and reducing agent. The formations of palladium nanoparticles were confirmed by UV-spectrophotometer while for morphology and nature, SEM and XRD were performed that confirmed the crystalline nature of PdNPs and proved the roughly spherical shape of nanoparticles. FT-IR analysis showed different functional groups of reducing agent and proved that guar gum have the ability to stabilized as well as to reduce the Pd (II) to Pd (0). Specific signal for the palladium is present in EDX spectra that further confirmed the formation of PdNPs. The catalytic efficiency was studied using the hydrogenation of 4-nitrophenol. Rate constant of prepared nano-catalyst was 0.1436/min, its efficiency, TON, TOF, in above mention reaction is 90.83, 27.78, and 185.2/hrs, respectively. Data obtained proved synthesized PdNPs to be efficient heterogeneous catalyst for the reduction of 4-NP and for the degradation of azo dyes.

The aim of the presented work was to assess the potential of Medicago polymorpha extract to synthesize silver nanoparticles (AgNPs) as a green method. It was a simple one-step synthesis approach and the product obtained was characterized by UV-visible spectroscopy, Fourier transform infrared (FTIR), powder X-ray diffraction, thermogravimetric analysis, and field-emission scanning electron microscopy (FE-SEM). At room temperature, the optimum time for the completion of the reaction (i.e. the formation colloidal solution) was just 5 min. FE-SEM images showed that AgNPs were predominantly in spheres, whereas FTIR spectrum analysis inferred that gallic acid present in the extract initially reduced silver ions to elemental silver. The carboxylic and hydroxyl groups of biomolecules present in the extract stabilized AgNPs by passivating the surface to prevent aggregation, resulting in uniform distribution. The antibacterial activity of synthesized AgNPs showed effective inhibitory effects against waterborne pathogens, including Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), at a minimum inhibitory concentration of 10 μg/ml. Membrane permeability and respiration studies were also performed to assess the surface role of the synthesized AgNPs. The prepared AgNPs exhibited excellent antioxidant activity and catalytic reduction of methyl orange with a rate constant of 6.8×10−3 s−1.

In this study, plant-mediated copper nanoparticles (CuNPs) were synthesized. Due to its direct synthesis mechanism and eco-friendly nature, the current method accounts for the green chemistry approach using the fruit extract of Duranta erecta for the first time. The UV-visible spectrum of the CuNPs solution showed a distinct absorption peak at 588 nm. Fourier transform infrared spectroscopy confirmed that the fruit extract is responsible for the reduction as well as the stabilization of CuNPs. X-ray diffraction patterns conform the crystalline nature of CuNPs. Energy-dispersive X-ray spectroscopy was performed for elemental analysis whereas field emission scanning electron microscopy was carried out for surface morphology. Prepared CuNPs were used for the reduction of carcinogenic azo dyes methyl orange (MO) and congo red (CR). CuNPs exhibit outstanding catalytic reduction for MO and CR in the presence of NaBH4 as reducing agents with the pseudo-first-order rate constants of 8.6×10−3 s−1 and 5.07×10−3 s−1 for MO and CR, respectively. Thus, natural plant materials act as cheap and environmentally friendly support for the synthesis of CuNPs and could be used for the purification of water from organic dye effluents.

Cercetările asupra potenţialului antioxidant din legume prezintă o importanţă crescută a efectelor sale asupra sănătaţii umane. Cu toate acestea, puţine studii au fost realizate pentru a investiga efectul antioxidant al extractului crud şi/sau a diferitelor fracţiuni din Brassica rapa L. În studiul de faţă, potenţialul antioxidant al extractului crud şi a fracţiunilor acestuia din fructul Brassica rapa L. a fost testat pentru enzimele glutation peroxidaza (GPx), superoxid dismutaza (SOD) şi statusul total antioxidant (STA) în probe de sânge. Rezultatele noastre au arătat faptul că atât extractul crud cât şi fiecare fracţiune analizată (apoasă, de acetat de etil şi cloroformică) au arătat efecte dependente de concentraţie asupra GPx, SOD şi STA în comparaţie cu soluţia salină (0,9% NaCl) folosită ca şi control negativ şi vitamina C, ca şi control pozitiv. Prin urmare, nivelurile GPx au prezentat valori crescute în extractul crud şi fracţiunea cloroformică (6981 U/L ambele la 10 mg/ml), nivelurile SOD au prezentat aceleaşi rezultate în fracţiunea apoasă şi cea de acetat de etil (220 U/ml ambele la 10 mg/ml) şi STA în extractul crud şi toate cele trei fracţiuni (apoasă, de acetat de etil şi cloroformică; 1,68 mmol/L la 10 mg/ml pentru toate fracţiunile) în comparaţie cu soluţia salină (p