Facile Synthesis of gC3N4-Exfoliated BiFeO3 Nanocomposite: A Versatile and Efficient S-Scheme Photocatalyst for the Degradation of Various Textile Dyes and Antibiotics in Water.

Water pollution engendered from textile dyes and antibiotics is a globally identified precarious concern that is causing dreadful risks to human health as well as aquatic lives. This predicament is escalating the quest to develop competent photocatalysts that can degrade these water pollutants under solar light irradiation. Herein, we report an efficient photocatalyst comprising a hierarchical structure by integrating the layered graphitic carbon nitride (gC3N4) with nanoflakes of exfoliated BiFeO3. The coexistence of these two semiconducting nanomaterials leads to the formation of an S-scheme heterojunction. This nanocomposite demonstrated its excellent photocatalytic activity toward the degradation of several textile dyes (Yel CL2R, Levasol Yellow-CE, Levasol Red-GN, Navy Sol-R, Terq-CL5B) and various antibiotics (such as tetracycline hydrochloride (TCH), ciprofloxacin (CPX), sulfamethoxazole (SMX), and amoxicillin (AMX)) under the simulated solar light irradiation. As this photocatalyst exhibits its versatile activity toward the degradation of several commercial dyes as well as antibiotics, this work paves the path to develop a reasonable, eco-benign, and highly efficient photocatalyst that can be used in the practical approach to remediate environmental pollution.

GA-AuNP@Tollens' complex as a highly sensitive plasmonic nanosensor for detection of formaldehyde and benzaldehyde in preserved food products.

Food preservatives nowadays are widely used chemicals throughout the food industries due to their commercial importance in increasing the shelf life of foods. But daily consumption of these preserved food products may be fatal to human health. Among different aldehydic compounds, formaldehyde and benzaldehyde are mainly used for preservation. Therefore, we reported a study on simple, selective and sensitive non-enzymatic detection of formaldehyde and benzaldehyde using GA-AuNP@Tollens'. Plasmonic resonance of GA-AuNP@Tollens' was taken as the basis for sensing formaldehyde and benzaldehyde in the linear range of 10-150 nM and 0.15-0.75 µM respectively. Both optimization and detection were acquired at UV absorbance of 409 nm. Detection limit of formaldehyde and benzaldehyde obtained through the proposed method was 20.08 nM and 0.12 µM respectively. Smartphone based detection method showed good linearity with R-Square value of 0.95 for both analytes. Lastly, GA-AuNP@Tollens' was implemented for the quantification of analytes in real samples.

CoFe2O4 Nanoparticles Grown within Porous Al2O3 and Immobilized on Graphene Nanosheets: A Hierarchical Nanocomposite for Broadband Microwave Absorption.

Demands to develop efficient microwave-absorbing materials are increasing with the advancement of information technology and the exponential rise in the usage of electromagnetic devices. To reduce electromagnetic interference and to overcome the adverse effects caused by microwave exposure resulting from the excessive usage of electromagnetic devices, microwave absorbers are very necessary. In addition, radar-absorbing materials are essential for stealth technology in military applications. Herein, we report a nanocomposite in which CoFe2O4 (CF) nanoparticles were grown within the porous structure of Al2O3 (PA), and this CoFe2O4-loaded Al2O3 (PA-CF) nanocomposite was immobilized on the surface of nanometer-thin graphene sheets (Gr). Owing to the hierarchical structure created by the constituents, the (60PA-40CF)90-Gr10 nanocomposite exhibited excellent microwave-absorption properties in the X-band region with a reflection loss (RL) value of ∼-30.68 dB (∼99.9% absorption) at 10.71 and 9.04 GHz when thicknesses were 2.0 and 2.3 mm, respectively. This nanocomposite demonstrated its competence as a lightweight, high-performance microwave absorber in the X-band region, which can be utilized in the applications of pioneering stealth technology.

CoFe2O4 Hollow Spheres-Decorated Three-Dimensional rGO Sponge for Highly Efficient Electrochemical Charge Storage Devices.

The energy demand, the crisis of fossil fuels, and the increasing popularity of portable and wearable electronics in the global market have triggered the demand to develop high-performance flexible all-solid-state supercapacitors that are capable of delivering high energy at high power density as well as being safely entrenched in those electronics. Herein, we have designed a nanocomposite, 80CFhs-20rGOsp, which exhibits a high specific capacitance (C S) value of 1032 F g-1 at 3 A g-1. Utilizing this nanocomposite as the cathode and reduced graphene oxide sponge (rGOsp) as the anode, a flexible all-solid-state asymmetric device has been fabricated. In this device, poly(vinyl alcohol) (PVA) gel embedded with a mixture of 3 M KOH and 0.1 M K4[Fe(CN)6] was used as an electrolyte cum separator. The fabricated device showed the capability to deliver an energy density of 65.8 W h kg-1 at a power density of 1500 W kg-1 and retained its capability even after various physical deformations. The device also exhibited a long cycle life and retained ∼96% of its C S value after 5000 cycles. Moreover, the fabricated flexible all-solid-state device successfully illuminated light-emitting diodes, which proved its potential use in real-life supercapacitor applications. The obtained results revealed the excellent electrochemical performances of the fabricated device and rendered it a promising candidate in the energy sector.

Dual-Purpose CuFe2O4-rGO-Based Nanocomposite for Asymmetric Flexible Supercapacitors and Catalytic Reduction of Nitroaromatic Derivatives.

Energy storage and environmental pollution are two major global concerns in today's scenario. As a result of the momentous exhaustion of fossil fuels, the generation of energy from renewable sources is gaining immense importance. However, the irregular availability of energy from these renewable sources is the major encounter to achieve sustainable energy harvesting technology, yielding efficient but continuous and reliable energy supplies. Apart from the requirement of state-of-the-art heavy-duty technologies such as transportation, defense, etc., in the modern lifestyle to fulfill the demand for flexible electronic devices, the development of high-performance mechanically flexible all-solid-state supercapacitors is increasing massively. On the other hand, to cater to the need for accessibility of clean water for healthy lives, several technologies are evolving to treat wastewater and groundwater. Hence, the development of efficient catalysts for destroying water pollutants is an attractive approach. Considering these two crucial facets, in this paper, we have demonstrated the multifunctional features of a CuFe2O4-rGO nanocomposite, which was exploited to fabricate a high-performance mechanically flexible all-solid-state asymmetric supercapacitor and simultaneously used as an efficient but easily recoverable catalyst for the transformation of different nitroaromatic compounds. We have also demonstrated the conversion of trifluralin (a herbicide), which is present in the water body as a pollutant, to its corresponding amine derivatives, which can be utilized in the preparation of important pharmaceutical products.

Solar Light-Irradiated Photocatalytic Degradation of Model Dyes and Industrial Dyes by a Magnetic CoFe2O4-gC3N4 S-Scheme Heterojunction Photocatalyst.

Magnetic CoFe2O4-gC3N4 nanocomposites were successfully synthesized, and their photocatalytic activities toward the decomposition of model synthetic dyes (e.g., methylene blue, methyl orange, and Congo red) in the presence of H2O2 were evaluated under simulated solar light irradiation. The 50CoFe2O4-50gC3N4 nanocomposite exhibited the highest catalytic activity. The catalytic activity of 50CoFe2O4-50gC3N4 toward the photodegradation of some industrially used dyes (such as Drimaren Turquoise CL-B p, Drimaren Yellow CL-2R p, and Drimaren Red CL-5B p) was also examined, and the catalyst exhibited its capability to decompose the industrial dyes completely. An aqueous mixture of these dyes was prepared to mimic the dye-containing wastewater, which was fully photodegraded within 30 min. 50CoFe2O4-50gC3N4 also exhibited facile magnetic separability from the reaction mixture after the accomplishment of photocatalysis reaction and stable performance after five cycles. The high photocatalytic efficiency to degrade several dyes, including dyes used in textile industries, under solar light irradiation makes 50CoFe2O4-50gC3N4 a promising photocatalyst for the treatment of dye-containing wastewater discharged from industries.