Nanopore-based devices have provided exciting opportunities to develop affordable label-free DNA sequencing platforms. Over a decade ago, graphene has been proposed as a two-dimensional (2D) nanopore membrane in order to achieve single-base resolution. However, it was experimentally revealed that clogging of the graphene nanopore can occur due to the hydrophobic nature of graphene, thus hindering the translocation of DNA. To overcome this problem, the exploration of alternative 2D materials has gained considerable interest over the last decade. Here we show that a Ti₂C-based MXene nanopore functionalized by hydroxyl groups (−OH) exhibits transverse conductance properties that allow for the distinction between all four naturally occurring DNA bases. We have used a combination of density functional theory and non-equilibrium Green’s function method to sample over multiple orientations of the nucleotides in the nanopore, as generated from molecular dynamics simulations. The conductance variation resulting from sweeping an applied gate voltage demonstrates that the Ti₂C-based MXene nanopore possesses high potential to rapidly and reliably sequence DNA. Our findings open the door to further theoretical and experimental explorations of MXene nanopores as a promising 2D material for nanopore-based DNA sensing.

基于纳米孔的设备为开发负担得起的无标记 DNA 测序平台提供了令人兴奋的机会。十多年前，石墨烯已被提出作为二维 (2D) 纳米孔膜，以实现单碱基分辨率。然而，实验表明，由于石墨烯的疏水性，石墨烯纳米孔可能会发生堵塞，从而阻碍 DNA 的易位。为了克服这个问题，在过去十年中，对替代二维材料的探索引起了相当大的兴趣。这里我们展示了一个 Ti ₂由羟基 (-OH) 官能化的 C 基 MXene 纳米孔表现出横向电导特性，可以区分所有四种天然存在的 DNA 碱基。我们结合使用密度泛函理论和非平衡格林函数方法对纳米孔中核苷酸的多个方向进行采样，如分子动力学模拟所产生。扫描施加的栅极电压导致的电导变化表明，基于 Ti ₂ C 的 MXene 纳米孔具有快速可靠地测序 DNA 的高潜力。我们的研究结果为进一步探索 MXene 纳米孔作为基于纳米孔的 DNA 传感的有前途的二维材料的理论和实验探索打开了大门。