Interlayer insertion has emerged as one of the key strategies for contact engineering in two-dimensional (2D) field-effect transistors (FETs). However, conventional interlayers such as hexagonal boron nitride (hBN) have limitations in contact performance and face challenges in achieving low-thermal-budget large-area fabrication. In this work, we explore the functionalization of printed ultrathin gallium oxide (GaO_x) films as tunneling contact layers in 2D transistors. Leveraging self-limiting oxidation of liquid gallium, we fabricate nanometer-thick GaO_x films (3.6 nm) that possess shallow defect states arising from oxygen vacancies, thereby narrowing the tunneling barrier width. When integrated as a tunneling layer in multilayer WS₂ field-effect transistors, the GaO_x film significantly enhances device performance, achieving a record electron mobility of 296 cm²·V⁻¹·s⁻¹, an ultra-low contact resistance of 2.38 kΩ·μm, and a minimal contact barrier height of 3.7 meV. Distinct from conventional insulating tunneling dielectrics, the observed performance enhancement originates from a hybrid tunneling mechanism within GaO_x, which is activated under the synergy of multiple electric fields and temperatures. Oxygen vacancies act as dynamic conduction channels that mediate composite tunneling pathways combining defect-assisted, direct, and Fowler–Nordheim tunneling, thus enabling efficient carrier injection across the interface. In addition, the low-temperature printing method also enables van der Waals integration in scalable fabrication without the Fermi pinning effect. This study not only demonstrates the new functional application of printed GaO_x films and clarifies the role of their oxygen vacancies in the tunneling mechanism but also proposes a novel, scalable strategy for optimizing contact engineering in low-dimensional electronic devices.

Multifunctional, wearable, and durable textiles integrated with smart electronics have attracted tremendous attention. However, it remains a great challenge to balance new functionalities with high-temperature stability. Herein, textile-based pressure sensors with excellent electromagnetic interference (EMI) shielding, Joule heating, and high-temperature resistance were fabricated by constructing graphene/SiC (G/SiC) heterostructures on carbon cloth via laser chemical vapor deposition (LCVD). The resultant textiles exhibited excellent EMI efficiency of 74.2 dB with a thickness of 0.45 mm, Joule heating performance within a low working voltage (V) range of 1–3 V, and fast response time within 20 s. These properties arose from multiple reflections, interfacial polarization, and high conductivity due to the numerous amounts of nanoscale G/SiC heterostructures. More importantly, G/SiC/carbon fibers (CFs) demonstrated well high-temperature resistance with a heat resistance index (T_HRI) of 380.2 ℃ owing to the protection of a coating layer on the CFs upon oxidation. Meanwhile, the G/SiC/CFs presented good pressure-sensing performance with high sensitivity (S) of 52.93 kPa⁻¹, fast response time of 85 ms, and a wide pressure range of up to 186 kPa. These features imply the potential of the G/SiC/CFs as efficient EMI shielding, electrical heater, and piezoresistive sensor textiles.