In this study, mono silver (Ag) nanoparticles are used to prepare binary nanofluids (NH 3 /H 2 O binary mixture with Ag nanoparticles) for application of NH 3 /H 2 O absorption in a bubble absorber. The measurements uncertainty in repeatability of absorption rate is yielded within 2.80%. The NH 3 /H 2 O bubble absorption experiments are carried out in two cases, with or without the coolant (water). The results show that the mass transfer in binary nanofluids with the coolant is enhanced more than that without the coolant. With the coolant, the highest absorption rate enhancement is observed to be 55% at 0.02 wt% Ag nanoparticles. In addition, the mass transfer enhancement by the binary nanofluids is discussed in detail.