Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela, Santiago de Compostela 15782, Spain.
School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
ACS Appl Mater Interfaces. 2023 May 3;15(17):21375-21383. doi: 10.1021/acsami.2c22495. Epub 2023 Apr 4.
Nanostructured carbon materials with tailor-made structures (e.g., morphology, topological defect, dopant, and surface area) are of significant interest for a variety of applications. However, the preparation method selected for obtaining these tailor-made structures determines the area of application, precluding their use in other technological areas of interest. Currently, there is a lack of simple and low-cost methodologies versatile enough for obtaining freestanding carbon nanostructures that can be used in either energy storage or chemical detection. Here, a novel methodology for the development of a versatile electrochemically active platform based on freestanding graphite nanoplatelets (GNP) has been developed by exploiting the interiors of hollow carbon nanofibers (CNF) comprising nanographene stacks using dry ball-milling. Even though ball-milling could be considered as a universal method for any carbonaceous material, often, it is not as simple (one step, no purification, and no solvents), efficient (just GNP without tubular structures), and quick (just 20 min) as the sustainable method developed in this work, free of surfactants and stabilizer agents. We demonstrate that the freestanding GNP developed in this work (with an average thickness of 3.2 nm), due to the selective edge functionalization with the minimal disruption of the basal plane, can act either as a supercapacitor or as a chemical sensor, showing both a dramatic improvement in the charge storage ability of more than 30 times and an enhanced detection of electrochemically active molecules such as ascorbic acid with a 236 mV potential shift with respect to CNF in both cases. As shown here, GNP stand as an excellent versatile alternative compared to the standard commercially available carbon-based materials. Overall, our approach paves the way for the discovery of new nanocarbon-based electrochemical active platforms with a wide electrochemical applicability.
具有定制结构（例如形态、拓扑缺陷、掺杂剂和表面积）的纳米结构碳材料在各种应用中都具有重要意义。然而，为了获得这些定制结构而选择的制备方法决定了其应用领域，使其无法应用于其他感兴趣的技术领域。目前，缺乏简单且低成本的方法来获得可用于储能或化学检测的独立式碳纳米结构，而这些方法需要足够的通用性。在这里，通过利用空心碳纳米纤维（CNF）内部的纳米石墨烯堆，开发了一种基于独立式石墨纳米片（GNP）的通用电化学活性平台的新方法，该方法采用干球磨。尽管球磨可以被认为是任何碳质材料的通用方法，但通常情况下，它并不像本工作中开发的可持续方法那样简单（一步法、无需纯化、无需使用溶剂）、高效（只得到 GNP 而没有管状结构）和快速（只需 20 分钟），而且该方法无需使用表面活性剂和稳定剂。我们证明，由于选择性地对边缘进行功能化，同时最小程度地破坏基面，本工作中开发的独立式 GNP（平均厚度为 3.2nm）既可以作为超级电容器，也可以作为化学传感器，在这两种情况下，其电荷存储能力都提高了 30 多倍，并且对电化学活性分子（如抗坏血酸）的检测能力也得到了增强，相对于 CNF，其检测的电位移动了 236mV。如这里所示，GNP 是一种比标准商业碳基材料更优秀的通用替代品。总体而言，我们的方法为发现具有广泛电化学适用性的新型纳米碳基电化学活性平台铺平了道路。
