Since the discovery of buckminsterfullerene over 30 years ago, sp²-hybridised carbon nanomaterials (including fullerenes, carbon nanotubes, and graphene) have stimulated new science and technology across a huge range of fields. Despite the impressive intrinsic properties, challenges in processing and chemical modification continue to hinder applications. Charged carbon nanomaterials (CCNs), formed via the reduction or oxidation of these carbon nanomaterials, facilitate dissolution, purification, separation, chemical modification, and assembly. This approach provides a compelling alternative to traditional damaging and restrictive liquid phase exfoliation routes. The broad chemistry of CCNs not only provides a versatile and potent means to modify the properties of the parent nanomaterial but also raises interesting scientific issues. This review focuses on the fundamental structural forms: buckminsterfullerene, single-walled carbon nanotubes, and single-layer graphene, describing the generation of their respective charged nanocarbon species, their interactions with solvents, chemical reactivity, specific (opto)electronic properties, and emerging applications.

A linker-controlled strategy has been demonstrated to synthesize polymeric photocatalysts for efficient H ₂ evolution by UV-Vis-IR with benchmark quantum yields.

The bandgap engineering of semiconductors, in particular low‐cost organic/polymeric photocatalysts could directly influence their behavior in visible photon harvesting. However, an effective and rational pathway to stepwise change of the bandgap of an organic/polymeric photocatalyst is still very challenging. An efficient strategy is demonstrated to tailor the bandgap from 2.7 eV to 1.9 eV of organic photocatalysts by carefully manipulating the linker/terminal atoms in the chains via innovatively designed polymerization. These polymers work in a stable and efficient manner for both H₂ and O₂ evolution at ambient conditions (420 nm < λ < 710 nm), exhibiting up to 18 times higher hydrogen evolution rate (HER) than a reference photocatalyst g‐C₃N₄ and leading to high apparent quantum yields (AQYs) of 8.6%/2.5% at 420/500 nm, respectively. For the oxygen evolution rate (OER), the optimal polymer shows 19 times higher activity compared to g‐C₃N₄ with excellent AQYs of 4.3%/1.0% at 420/500 nm. Both theoretical modeling and spectroscopic results indicate that such remarkable enhancement is due to the increased light harvesting and improved charge separation. This strategy thus paves a novel avenue to fabricate highly efficient organic/polymeric photocatalysts with precisely tunable operation windows and enhanced charge separation.

Single-walled carbon nanotubes (SWNTs) are a fundamental family of distinct molecules, each bearing the possibility of different reactivities due to their intrinsically distinct chemical properties. SWNT syntheses generate a heterogeneous mixture of species with varying electronic character, lengths, diameters and helicities, (n,m), as well as other amorphous, graphitic and metal catalyst impurities. In recent years, selective syntheses and post-synthetic separation strategies have advanced, driven by the requirement for pure SWNTs displaying particular features. Covalent surface modifications are widely-used to adapt SWNTs for specific applications with modified solubility, compatibility and specific functionalities. In many cases, such reactions have been found to be selective, illuminating the fundamentally distinct chemistry of each (n,m) species. This differential reactivity has found immediate utility in facilitating the sorting of nanotubes according to specific diameter, electronic properties and, most importantly, helicity. In this tutorial review, we discuss a wide range of selective reactions, the mechanisms that are thought to govern selectivity, and the challenges of separating, characterising and regenerating the modified SWNTs.

With a rising emphasis on public safety and quality of life, there is an urgent need to ensure optimal air quality, both indoors and outdoors. Detecting toxic gaseous compounds plays a pivotal role in shaping our sustainable future. This review aims to elucidate the advancements in smart wearable (nano)sensors for monitoring harmful gaseous pollutants, such as ammonia (NH₃), nitric oxide (NO), nitrous oxide (N₂O), nitrogen dioxide (NO₂), carbon monoxide (CO), carbon dioxide (CO₂), hydrogen sulfide (H₂S), sulfur dioxide (SO₂), ozone (O₃), hydrocarbons (C_xH_y), and hydrogen fluoride (HF). Differentiating this review from its predecessors, we shed light on the challenges faced in enhancing sensor performance and offer a deep dive into the evolution of sensing materials, wearable substrates, electrodes, and types of sensors. Noteworthy materials for robust detection systems encompass 2D nanostructures, carbon nanomaterials, conducting polymers, nanohybrids, and metal oxide semiconductors. A dedicated section dissects the significance of circuit integration, miniaturization, real-time sensing, repeatability, reusability, power efficiency, gas-sensitive material deposition, selectivity, sensitivity, stability, and response/recovery time, pinpointing gaps in the current knowledge and offering avenues for further research. To conclude, we provide insights and suggestions for the prospective trajectory of smart wearable nanosensors in addressing the extant challenges.