Comprehensive study of CO2capture performance under a wide temperature range using polyethyleneimine-modified adsorbents

•The adsorbents are tested under a wide temperature range covering most of the CO2capture applications required.•The influence of PEI loadings and molecular weights is discussed comprehensively based on different evaluation indicators.•The suppression and promotion effect of temperature are considered as the main inherent reasons.•Fast and slow adsorption processes are divided quantitatively to analyze the adsorption kinetic for the first time.