Efficient absorption and thermodynamic modeling of nitric oxide by low viscous DBU-based N-heterocyclic deep eutectic solvents

•The DBU-based N-heterocyclic DESs exhibited low viscosity of 10.02 mPa·s at 293.2 K.•The solubility of NO in the DBU-based N-heterocyclic DESs could reach up to 5.10 mol·kg−1 at 293.2 K and 1 bar.•RETM was designed to correlate the NO experimental solubility to obtain the thermodynamic parameters.•Absorption mechanism was verified that there was a chemical interaction between NO and the N-heterocyclic compounds.