High-Performance VA-MoS$_{2}$/GO Heterostructure-Based Sensor for In-Situ Soil Moisture Sensing

This letter presents a vertically aligned (VA)-MoS$_{2}$/graphene oxide (GO) heterostructure-based resistive sensor designed for high-performance soil moisture monitoring. The sensing film is fabricated using chemical vapor deposition to grow VA-MoS$_{2}$ nanoflakes, followed by a spin coating of a colloidal GO solution. The sensor achieves a response of approximately 8.4% at 20% relative humidity (RH) and 41.18% at 80% RH, which demonstrates a broad detection range with high sensitivity. It also exhibits excellent stability, repeatability, and fast response and recovery times. In soil moisture measurement experiments, the sensor shows % responses of around 64.3, 139.8, and 160.67 for black soil with moisture contents of 5.9%, 16.2%, and 19.3%, respectively. With its wide sensing range, linear response, reliable performance, and cost-effective and scalable fabrication process, the VA-MoS$_{2}$/GO heterostructure holds great promise for next-generation soil moisture monitoring applications.