The invention of carbon and its allotropes have transformed the electronic and optoelectronic industry due to their encouraging properties in a large spectrum of applications. The interesting characteristic of carbon is its ability to form many allotropes due to its valency. In recent decades, various allotropes and forms of carbon have been invented, including fullerenes, carbon nanotubes (CNTs), and graphene (GR). Since the inception of nanotechnology, carbon allotropes-based nanocomposites have become a leading sector of research and advancement due to their unique bonding properties. Fullerenes and CNTs-based polymer nanocomposites have attracted significant research interest due to their vast applications in every sphere of science and technology. Current research impetus reveals that carbon and its allotropes have revolutionized the industry and academia due to their fascinated properties. Recent advances in various aspects of graphene, CNTs, graphene nanoribbons, fullerenes, carbon encapsulates, and their nanocomposites with polymeric materials and their different applications are reported in this review article. Also, current status and future prospects of graphene-based polymer nanocomposites are presented in common along with proper citations extracted from the scientific literature. Moreover, this article is a unique collection of vital information about GR, CNTs, fullerenes, and graphene-based polymer nanocomposites in a single platform.

This paper explores the possibility of dealing with two major challenges of the contemporary world, i.e., waste management and storage of energy. This study presents the extraction and application of cellulose (from waste paper) based composites for supercapacitor electrodes with a view to mitigate the energy crisis. In situ polymerization is used for the synthesis of benign composites comprising cellulose, polypyrrole (PPy) and graphene. It has been observed that inclusion of cellulose in PPy increases the specific capacitance by 318% with moderate energy density and appreciably high power density compared to PPy alone. Similar results are obtained for graphene/PPy/cellulose composites where a 273% increase of specific capacitance is observed with the incorporation of cellulose in graphene/PPy composites without deteriorating the cyclic stabilities of the electrode materials.

Synthetic dyes are preferred in wide range of industries due to their cost-effectiveness. However, resulting partially or untreated effluents from these has been reported to be carcinogenic as well as possess potential threat to the environment. This attracted great deal of scientific attention encompassing several methods (like coagulation, membrane filtration, advanced oxidation process etc.) to irradicate industrial effluents. Despite of great efforts, it remains challenging and requires sustainable approach in existing technologies. Herein, this review extensively highlights the fundamental concepts of dyes, their classification, degradation mechanism, and key challenges. The objective of this review is to provide the comparative analyses of (i) Dye removal technologies with respect to efficacy of environmental protection, health (ii) Understanding of various parameters affecting dye adsorption process and (iii) Challenges involved and techno-economic assessments of dyes containing water treatment. Herein, selection of materials (like particle size, surface charge density), preferential adsorption behavior of dyes, reaction parameters (such as adsorbent dosage/initial dye concentration) and pH of the solution have also been discussed in detail. From a techno-economic perspective feasibility of technologies for dyes containing water are also examined in context of sustainability.

A natural layered clay known as montmorillonite, a lamellar aluminosilicate with ∼1 nm thickness, has attracted intense attention in ongoing research due to its large natural abundance and environmental friendliness. Endowed with highly active surface sites the nanoclay has been extensively used in various fields viz. catalysis, biosensors etc. even though the role played by nanoclay on energy storage performance has not been elucidated. In this present work, a series of nanoclay (Closite 30B) based hierarchical open interconnected mesoporous electrode materials for supercapacitors (SCs) has been synthesized in the presence of carbon nanotubes (CNTs) and polypyrrole (PPy) by a facile in situ and ex situ approach. The role of nanoclay was explored as a dopant and its substantial doping effect exerted on the electrochemical performance towards energy storage was investigated. A coating of PPy over CNTs and nanoclay was confirmed from FESEM analysis which revealed the genesis of a nanoclay-supported hierarchical interconnected mesoporous framework. Furthermore, a PPy-coated CNT array in the presence of nanoclay was found to be highly porous with a high specific surface area without obvious deterioration. These interconnected structures can contribute to better penetration of electrolyte ions by shortening the path length for rapid transport of ions and electrons even at high rates. Cyclic voltammetry measurements revealed that nanoclay based in situ composite (CNP) and ex situ composite (CPN) exhibited a maximum specific capacitance of 425 F g⁻¹ and 317 F g⁻¹, respectively at a scan rate of 10 mV s⁻¹, which is comparatively higher than that of CP (i.e. PPy-coated CNTs) (76.77 F g⁻¹). Similarly, a 273% increase in the specific capacitance of PPy was achieved after nanoclay incorporation in the nanocomposite NP (i.e. PPy-coated nanoclay) as compared to virgin PPy. These results are in good agreement with the specific capacitance performance by galvanostatic charging–discharging analysis performed at 5 A g⁻¹. It was also found that all the nanocomposite retains about 94% initial specific capacitance even after 2000 consecutive cycles. Thus, this kind of nanoclay-based hierarchical nanostructured framework is believed to be extremely beneficial for SCs applications.