1：Experimental Design and Method Selection:

The study utilized a graphene oxide film (GOF) with a gradient of oxygen-containing groups (g-GOF) for IR detection. The interaction between water and GO, including adsorption and desorption stimulated by IR light, was exploited to generate electric signals.

2：Sample Selection and Data Sources:

GO was prepared using an improved Hummer's method. The g-GOF was fabricated by applying a bias voltage to the GOF under controlled humidity to establish a gradient of O-groups.

3：List of Experimental Equipment and Materials:

Equipment included a Keithley 6514 electrometer for current measurement, an AFM for GO morphology observation, and an FTIR microscope for IR transmittance spectrum measurement. Materials included nano-graphite, sodium nitrate, sulfuric acid, potassium permanganate, and hydrogen peroxide for GO preparation.

4：Experimental Procedures and Operational Workflow:

The g-GOF was exposed to water vapor at near-saturated pressure, then illuminated with IR light to stimulate water desorption and generate electric signals. The response to humidity changes and IR illumination was measured.

5：Data Analysis Methods:

The temperature sensitivity and current responsivity were calculated based on the change of current and surface temperature upon IR illumination.