A DFT study of dissolved gas (C2H2, H2, CH4) detection in oil on CuO-modified BNNT

In this work, CuO modified BNNT surface was investigated by DFT calculation. We suppose that BNNT is a potential gas sensitive material. The modified model is present, and the combination between CuO and BNNT proved to be stable by DFT. Besides, CuO-modified BNNT shows high reactivity and sensitivity toward dissolved gas in oil. After the adsorption of dissolved gas in oil, and the adsorption capacity occurred in the following order: C2H2 > H-2 > CH4. CuO-BNNT has a chemical adsorption effect on C2H2 only. Meanwhile, band gap of the system increased by 72.0% after the adsorption of C2H2, which leading to a significant decrease in conductivity. Importantly, the recovery time at room temperature (298 K) is significantly shorter than other recently proposed materials. The CuO-BNNT system shows excellent gas-sensitive response to C2H2, but low sensitivity to CH4 and H-2. This allows detection of C2H2 in certain gas environments without interference.