Carbon nanomaterials (CNMs), including fullerenes, carbon nanotubes, graphene, nanodiamonds and their derivatives, have been extensively used for biomedical applications, especially for cancer diagnosis and treatment. Most of these applications require covalent reactions to give the CNMs a high dispersibility in physiological environments, new biological functions for diagnosis and treatment, and tailored interactions with biological systems for efficient therapy. In this review, we summarize: the covalent bonding approaches to functionalize CNMs with polar surface groups, hydrophilic polymer layers, and bioactive molecules, and the specific surface chemistry that can prevent the interactions of CNMs with plasma proteins to suppress non-specific uptake and to enhance targeted uptake, aiming to advance the design of CNM-based therapeutics for precise theranostics.

Over the past decade, graphene oxide (GO), an oxidized derivative of graphene, has been extensively used in various fields such as water treatment, ion sieving, gas separation, drug delivery, sensing, and energy storage due to the presence of oxygen-containing functional groups, which provide GO with intrinsic hydrophilicity, dispersibility, superpermeability, and insulating properties. Furthermore, depending on the requirements of different applications, these groups can be modified by bonding with various organic functional groups to improve these characteristics. This chemical modification approach is known as functionalization, and can be divided into covalent and non-covalent depending on the bonding between the GO and the additive. Although both covalent functionalization and non-covalent functionalization can be used with GO, covalent functionalization has greater versatility in terms of the modification mechanisms and long-term stability. In this review, we focus on the covalent functionalization of GO and discuss four effective covalent functionalization methods, which are determined by the specific oxygen-containing functional groups. We explain their respective functionalization mechanisms and finally summarize the impact of covalent functionalization on GO and explore its future potential.

Chemical hydrogen storage is expected to be a suitable alternative to the conventional physical storage methods for hydrogen, and formic acid (FA) has great potential among the renewable hydrogen storage materials studied so far. Thus, the development of promising catalysts that target H₂ storage or supply, mediated by formic acid/CO₂, is greatly needed. However, the use of reliable heterogeneous catalysts has been delayed because research has concentrated on soluble homogeneous catalysts. The state-of-the-art in the development of heterogeneous catalysts with precise structures aimed at these reactions is summarized. We especially focus on the modification of carbon-based support materials with surface-grafted amine groups, which not only alter the electronic structures of the active nanoparticles, but also optimize the interaction with FA and CO₂ and improve the catalytic activity.

Recently, the demand for high-performance secondary batteries with high capacities, long lifespans, and low cost has increased. We focus on a Tin (Sn) electrode as a high-capacity anode material for sodium-ion batteries and attempt to improve battery performance using its composites with various carbon materials (CMs). Electrode materials of micrometer-sized Sn powder and composites of Sn with three types of CMs were prepared by mechanical milling for 6 h. 2032-type coin cells were assembled, and constant current charge–discharge tests were performed for up to 50 cycles. The Sn/C composite anodes maintained high discharge capacities of 389–635 mAh g⁻¹ after 50 cycles, which are significantly higher than that off an electrode prepared using only Sn (132 mAh g⁻¹). The highest capacity was obtained using acetylene black as the CM. All the Sn/C composites prepared by mechanical milling had a larger specific surface area and more gaps than only Sn. As a result, stress was easily dispersed during the expansion and contraction of the electrode in the alloying and dealloying processes, which prevented the exfoliation of the active material during cycling and remarkably improved the battery performance.

A novel porous carbon was fabricated by intercalating fullerene between graphene sheets. The fullerene/graphene porous composites were prepared by the lamination of graphene and fullerene, and their adsorption of water vapor was evaluated. Those with less than 10 graphene layers were hydrophobic, but the amount of water adsorbed then increased with the number of stacked layers. The simulated adsorption of water by these materials using grand canonical Monte Carlo simulations indicated that the slightly stronger interaction potentials of the composites facilitated water adsorption.