Gated MoS2/SiN Nanochannel for Tunable Ion Transport and Protein Translocation

Abstract Ionic transport in nanofluidic channels holds great promise for applications such as single-molecule analysis, molecular manipulation, and energy harvesting. However, achieving precise control over ion transport remains a major challenge. In this work, we introduce a MoS₂/SiN hybrid nanochannel architecture that enables electrical tuning of ionic transport via external gating, and we examine its potential for osmotic power generation and single-molecule detection. To fabricate the channels, we employed a combined focused ion beam (FIB) milling and dry transfer method, producing sub-10 nm thick structures while preserving the structural integrity and electronic properties of MoS₂—essential for reliable surface charge modulation. We first investigated how the gate voltage influences ionic conductance, finding evidence of gate-dependent modulation of ion selectivity under different bias polarities. Next, by applying a salt concentration gradient across the nanochannels, we demonstrated the feasibility of this platform for osmotic energy harvesting. Finally, we tested the system for single-molecule sensing, showing that linearized bovine serum albumin (BSA) produced translocation signals with notably long dwell times. Together, these results highlight gated MoS₂/SiN nanochannels as a promising platform for tunable nanofluidics, with potential applications in controlled molecular transport and energy harvesting from osmotic gradients.