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Graphene is an advanced carbon functional material with inherent unique properties that make it suitable for a wide range of applications. It can be synthesized through either the top–down approach involving delamination of graphitic materials or the bottom–up approach involving graphene assembly from smaller building units. Common top–down approaches are exfoliation and reduction while bottom–up approaches include chemical vapour deposition, epitaxial growth, and pyrolysis. A range of materials have been successfully used as precursors in various synthesis methods to derive graphene. This review analyses and discusses the suitability of conventional, plant- and animal-derived, chemical, and fossil precursors for graphene synthesis. Together with its associated technical feasibility and economic and environmental impacts, the quality of resultant graphene is critically assessed and discussed. After evaluating the parameters mentioned above, the most appropriate synthesis method for each precursor is identified. While graphite is currently the most common precursor for graphene synthesis, several other precursors have the potential to synthesize graphene of comparable, if not better, quality and yield. Thus, this review provides an overview and insights into identifying the potential of various carbon precursors for large-scale and commercial production of fit-for-purpose graphene for specific applications.

A natural polymer-based iron oxide (Fe3O4) nanocomposite was prepared through a sonochemical-assisted precipitation method. Characterization studies such as X-ray diffractometer, scanning electron microscopy, and transmission electron microscopy have revealed that the synthesized nanocomposites are homogenously distributed, having an average size of ~49 nm with a cubical spinel structure. The toxic 1-amino-nitrobenzene was initially treated with a sonophotochemical process in the presence of synthesized nanocomposites, resulting in lower efficiency, whereas with the addition of oxidants, the efficiency enhanced significantly. The parametric effects with respect to the initial solution pH, nanocomposites dose, 1-amino-nitrobenzene concentration, and oxidant concentration were studied, and it was found that an approximately 75% removal efficiency of 1-amino-nitrobenzene was achieved within 120 min. Further, the performance of the catalyst on the oxidation of 1-amino-nitrobenzene with sodium persulfate was also investigated, and it was found that a 95% removal efficiency was attained.

This work investigates the photocatalytic performance of V2O5 and V3O7 nanoparticles and their nanocomposites with rGO. The as-annealed V2O5 and V3O7 nanoparticles exhibited pure orthorhombic and monoclinic structures with an optical bandgap of 2.3 and 2.5 eV, respectively. The corresponding vibrational modes using Raman and FTIR spectroscopy analysis further confirm the form. The morphological studies reveal that V2O5 and V3O7 nanoparticles possess plate and petal-like morphology, respectively. Moreover, in the case of V2O5/V3O7—rGO nanocomposites, the plate/petal-like nanoparticles are embedded within rGO sheets. Incorporating nanoparticles within rGO sheets has quenched the green photoluminescence emission, enhancing their photocatalytic performance upon irradiation with white light of 100 mW/cm2. This is ascribed to the effective transport of interfacial electrons from vanadium oxide nanoparticles to the rGO surface, reducing the recombination of photogenerated charge carriers. These results indicate that the vanadium oxide/rGO nanocomposites have potential applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

Here, furfural oxidation was performed to replace the kinetically sluggish O2 evolution reaction (OER). Pt‐Co3O4 nanospheres were developed via pulsed laser ablation in liquid (PLAL) in a single step for the paired electrocatalysis of an H2 evolution reaction (HER) and furfural oxidation reaction (FOR). The FOR afforded a high furfural conversion (44.2%) with a major product of 2‐furoic acid after a 2‐h electrolysis at 1.55 V versus reversible hydrogen electrode in a 1.0‐M KOH/50‐mM furfural electrolyte. The Pt‐Co3O4 electrode exhibited a small overpotential of 290 mV at 10 mA cm−2. As an anode and cathode in an electrolyzer system, the Pt‐Co3O4 electrocatalyst required only a small applied cell voltage of ∼1.83 V to deliver 10 mA cm−2, compared with that of the pure water electrolyzer (OER∥HER, ∼1.99 V). This study simultaneously realized the integrated production of energy‐saving H2 fuel at the cathode and 2‐furoic acid at the anode. [ABSTRACT FROM AUTHOR]

The growing potential of sustainable materials such as polyhydroxyalkanoates (PHAs), polylactic acid (PLA), alginate, carrageenan, and ulvan for bioplastics production presents an opportunity to promote a sustainable circular economy. This review investigates their properties, applications, and challenges. Bioplastics derived from algae offer an environmentally friendly alternative to petroleum‐based plastics, a shift of paramount importance to society due to the escalating environmental concerns associated with traditional plastics. The role of the internet‐of‐things (IoT) and machine learning in refining these bioplastics' production and development processes is emphasized. IoT monitors cultivation conditions, data collection, and process control for more sustainable production. Machine learning can enhance algae cultivation, increasing the supply of raw materials for algal bioplastics and improving their efficiency and output. The study results indicate the promise of algae‐based bioplastics, IoT, and machine learning in fostering a more environmentally sustainable future. By harnessing these advanced technologies, optimization of bioplastic production is possible, potentially revolutionizing the materials industry and addressing existing challenges toward achieving a sustainable circular economy. [ABSTRACT FROM AUTHOR]