At PNNL removing carbon dioxide (CO2) from the gases emitted by coal-fired and other fossil-fueled power plants requires materials that can efficiently extract the CO2 while ignoring the other gaseous molecules. The materials must be capable of working in hot, moist environments without losing efficiency. PNNL researchers modified the surface of a material called a metal-organic framework (MOF) to render it better able to extract CO2 under the working conditions it might encounter. The MOF shown above was imaged at 20,000 times magnification using a focused ion beam scanning electron microscope. The proposed surface modification may be applicable to thousands of different MOF materials to improve moisture stability and increase selectivity towards CO2 extraction. This work will help to make fossil energy use more sustainable, safer and cleaner.