image (IMAGE) Science China Press Caption SnS2/black phosphorus heterostructure with suppressed Sn2+ and Lewis acidity enables the selective and sensitive detection of ppb-level NO2 gas at room temperature. Credit ©Science China Press Usage Restrictions Use with credit. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.