1：Experimental Design and Method Selection:

The study involved synthesizing 2D SnS2 flakes via a wet chemical route, fabricating conductometric sensors by depositing the flakes on Pt-interdigitated alumina substrates, and performing in situ annealing at various temperatures (200-400°C) in air to form hybrid SnS2-SnO2-x phases. Sensing tests were conducted towards ammonia gas.

2：Sample Selection and Data Sources:

The sensing material was 2D SnS2 powder synthesized from tin(IV) chloride and sulfide precursors. Sensors were fabricated on alumina substrates with Pt electrodes.

3：List of Experimental Equipment and Materials:

Equipment includes a Schlenk line for synthesis, centrifuge for separation, drop-casting for deposition, Agilent E3632A power supply for heating, Keithley 6487 Picoammeter/Voltage Source for resistance measurement, mass flow controllers for gas dilution, Bruker D8 Advance X-ray diffractometer for XRD, Craic 20-30 micro-spectrophotometer for Raman spectroscopy, ZEISS 1540XB FE SEM for SEM and EDX analysis. Materials include SnCl4·5H2O, oleic acid, octadecene, sulfide powder, oleylamine, ethanol, hexane, alumina substrates, Pt electrodes, synthetic air, and ammonia gas.

4：Experimental Procedures and Operational Workflow:

Synthesis involved degassing and heating precursors, injection, reaction, centrifugation, washing, and dispersion. Sensors were fabricated by drop-casting the suspension and annealing in situ. Sensing tests were performed in a stainless-steel chamber with controlled gas flow and temperature, measuring resistance changes.

5：Data Analysis Methods:

Sensor response was defined as Ra/Rg, with response and recovery times measured. Data were analyzed to correlate annealing temperature with morphological, microstructural, and electrical changes using techniques like XRD, Raman, SEM, and EDX.