Li Hong, Canton-Vitoria Ruben, Urano Yuto, Nayak Sudhanshu Kumar, Yamamoto Eisuke, Kobayashi Makoto, Kitaura Ryo, Osada Minoru
Department of Materials Chemistry & Institute of Materials and Systems for Sustainability (IMaSS), Nagoya University, Nagoya, 464-8601, Japan.
Joining and Welding Research Institute, Osaka University, Osaka, 567-0047, Japan.
Small. 2025 Sep;21(38):e03895. doi: 10.1002/smll.202503895. Epub 2025 Aug 3.
MXenes such as TiC and TiCN are 2D materials characterized by the presence of a T phase that passivates the reactive titanium surface. Modifying their chemical composition to anchor target molecules is of great interest for addressing key challenges, such as enhancing the conversion of visible light into electricity. In this study, a covalent functionalization strategy is developed to modify the T phase of TiC or TiCN with alkyl amines, followed by coupling with Zn-porphyrin. This process activates the optical properties of MXenes without causing any damage. X-ray photoelectron spectroscopy and infrared spectroscopy are pivotal in confirming the covalent functionalization, while thermogravimetric analysis, transmission electron microscopy, and additional techniques provided further insights into structural and chemical features. Spectroelectrochemical investigations reveal carrier injection into MXenes under light illumination, potentially enhancing conductivity. Photodetectors fabricated from these films demonstrate responsivities of 1.4-15.0 A W and external quantum efficiencies ranging from 1300 to 2830% in the visible range, making them comparable to well-established hybrid 2D nanomaterials like MoS and WS.
诸如TiC和TiCN之类的MXenes是二维材料，其特征在于存在使活性钛表面钝化的T相。改变它们的化学成分以锚定目标分子对于解决关键挑战（如提高可见光到电的转换效率）具有重要意义。在本研究中，开发了一种共价功能化策略，用烷基胺修饰TiC或TiCN的T相，然后与锌卟啉偶联。该过程激活了MXenes的光学性质而不会造成任何损害。X射线光电子能谱和红外光谱对于确认共价功能化至关重要，而热重分析、透射电子显微镜和其他技术则进一步深入了解了结构和化学特征。光谱电化学研究表明，在光照下载流子注入到MXenes中，这可能会提高导电性。由这些薄膜制成的光电探测器在可见光范围内的响应度为1.4-15.0 A/W，外量子效率在1300%至2830%之间，使其与诸如MoS和WS等成熟的混合二维纳米材料相当。
