A facile strategy to rapidly screening gas-sensitive materials in large samples: A case study of surface modified SnO₂ for CH₄ detection

It is crucial that the Methane (CH ₄ ) explosion is a gas accident that severely restricts the safety of coal mines, so the detection of methane. This paper reviews the design and development of metal oxide nanomaterials, followed by accenting an outlook in conjunction with the idea of parallel synthesis. To begin with, 18 different concentrations of rare earth and precious metal elements were modified on the surface of SnO ₂ nanoparticles, respectively, by a parallel synthesis platform. Then, the material composition and surface morphology of the samples were analyzed by the X-ray diffraction technique and the field emission scanning electron microscopy. Finally, the gas-sensitive properties of the obtained 91 gas-sensitive materials were studied simultaneously for CH ₄ gas using an unmanned high-throughput gas-sensitive test platform assembled in-house. The test results show that the 0.2 mol% Yttrium-modified SnO ₂ sensor has an ultra-high gas-sensitive response (Rair/ Rgas= 33.7) to 1000ppm CH ₄ gas at 400°C, which is 25.9 times that of pure SnO ₂ sensor. In addition, the sensor exhibited stable repeatability. The performance enhancement of the SnO ₂ -based CH ₄ gas sensor with surface-modified metal elements is mainly due to the spillover effect of the metal elements and the promotion of the Schottky barrier, both of which synergistically enhance the gas-sensitive performance of the material.