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Graphene-based nanocomposites with conducting polymers have attracted increasing interest due to the enhanced synergistic properties, which can potentiate and broaden applications. In this context, covalent functionalization stands out as a strategic designing tool, which optimizes the interaction between the nanocomposites components. Herein, covalently linked polymeric nanocomposites were obtained between graphene derivatives and polypyrrole (Ppy) under mild routes (i.e., aqueous, room temperature). First, pyrrole was covalently functionalized on graphene oxide (GO) through stable amide bonds and further polymerization with FeCl 3 led to the polymeric nanocomposites. Finally, to improve conductivity, GO was reduced using NaBH 4 . Similarly, analogous noncovalent nanocomposites were obtained for comparison purposes. All samples were thoroughly characterized by thermogravimetric analysis, scanning electron microscopy, and infrared and Raman spectroscopy, confirming the targeted functionalization, polymerization, and reduction processes. Moreover, the covalent link effectively enhances the interaction of the nanocomposite's components as evidenced by its improved electrochemical stability (300 cycles), compared to the non-covalent composites which loses conductivity in the initial stages. Indeed, Ppy is known for its low stability, limiting its applications. Overall, the results herein evidence that covalently linked nanocomposites can be successfully obtained with optimized electrochemical response, promising for applications as supercapacitors and artificial muscles.

Chemical security has been a hot topic over several years, especially involving organophosphates (OP), which are related to organophosphorus chemical warfare and pesticides. The main challenges are to develop efficient ways to destroy stockpiles of these materials and also to monitor their presence in the field or food. A promising approach in this sense is the targeted design of catalysts that can react with OP and degrade them. Herein, we present a summary of some recent advances towards OP detoxification and monitoring that involves four different approaches: (i) How? Understanding the mechanism: thorough mechanistic elucidation and design of an ideal catalytic scaffold; (ii) Nanocatalysts and sensors: rational functionalization of carbon nanomaterials leading to nanocatalysts as powder and thin films. A surface-enhanced Raman scattering (SERS) sensor for OP was also obtained combining the functionalized material with silver nanoparticles; (iii) Catalysts from waste: reuse of rice husk waste as well as waste derived from the cheap gum arabic for developing biocatalysts that have high added-value and are environmentally friendly; (iv) A simple sensor: a simple, cheap and compact homemade colorimeter that can be used as a colorimetric sensor for detecting quantitatively various compounds, including pesticides.

Electrodes combining battery and supercapacitor materials are an alternative to enhance energy and power densities in energy storage devices. Herein, a material of graphene modified with the triruthenium acetate coordination compound was synthesized through covalent functionalization of graphene. The structure and chemical composition of the material were characterized using scanning electron microscopy and infrared, Raman, and X-ray photoelectron spectroscopies. The electrochemical characterization through cyclic voltammetry and discharge curves revealed that triruthenium cluster-functionalized graphene has excellent charge−discharge capability with a cycling retention over 98% after 5000 cycles. Also, a synergistic effect was found at low specific discharge currents, with contributions of the triruthenium cluster Faradaic process and graphene double-layer capacitance to the storage capacity. At a specific discharge current of 0.25 A g −1 , the capacity of triruthenium cluster-functionalized graphene is 1.2 times that of graphene, reaching a specific capacitance of 11 F g −1 , but the capacity is limited by charge transport at high current densities and scan rates.

Chemical functionalization with conductive polymeric monomers on carbon nanotubes carried out by a straightforward method.

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