Quantitative measurements of broad-band mid-infrared absorption spectra of formaldehyde, acetaldehyde, and acetone at combustion-relevant temperatures near 5.7 µm

•Employed a broad-scan, rapid-tuning EC-QCL for the collection of high-temperature absorption spectra in a shock tube.•Reported the formaldehyde absorption spectrum in its ν2 vibrational band at 998  K, 3.8  atm.•Measurements of formaldehyde cross sections showed reasonable agreement with HITRAN 2016.•Under predictions in spectral simulations were due to missing hotband and high-J rovibrational transitions.•Acquired the first-ever experimental high-temperature absorption spectra for acetaldehyde and acetone.