The depth-dependent laser-induced conversion of organic precursor coatings has successfully been utilized to fabricate a complete flexible sensor architecture for selective CO2 sensing at room temperature. The method exhibits decisive advantages for producing N-doped carbons from adenine as precursor: the gradual carbonization induces the formation of a crystalline transducer layer but retains the active binding sites in the less impacted, buried sensor layer. By introducing glucose as efficient foaming agent, the sensitivity is enhanced, as it systematically opens pore channels to access those active species. In turn, the active sites, i.e. imidazolic nitrogen, are preserved in the lower sensor layer. Systematic optimization of the sensor morphology and surface chemistry resulted in a drastic performance increase of almost two orders of magnitude.