Flexible hydrogen sensor with ultra-high sensitivity and wide range and fabrication method therefor

A method for fabricating a flexible hydrogen sensor, comprising the following steps:

• a step (1):
• ultrasonically cleaning a flexible polymer substrate with isopropanol, ethanol and deionized water in sequence for 5 min to 10 min, and blow-drying the flexible polymer substrate with high-purity nitrogen (99.999%) for later use;
• a step (2):
• depositing a layer of MOx film with a thickness of 5 nm to 50 nm at a low temperature to 350° C. by thermal atomic layer deposition (ALD) or plasma-enhanced ALD (PEALD) on the flexible polymer substrate treated in the step (1);
• a step (3):
• depositing Pd nanoparticles (NPs) with a coverage rate of 5% to 50% on the MOx film grown in the step (2) by a cluster beam deposition (CBD) technology so as to modify the MOx film, wherein the parameters of the CBD are as follows:
• the pressure of a chamber is 10−5 Pa, a cluster source is filled with 100 Pa argon during deposition, the purity of the metal Pd target used is not lower than 99.9999%, the sputtering power is 20 W to 50 W, and the condensation distance is 30 mm to 80 mm;
• a step (4):
• depositing a metal interdigital electrode with a thickness of 100 nm to 200 nm on the MOx film loaded with Pd NPs in the step (3) as a conductive electrode by a mask, and performing wiring and packaging to obtain a MOx-based flexible hydrogen sensor loaded with Pd NPs.