Novel SiO2-LiBr microcapsules for water-retaining pavement were prepared and firstly characterized by scanning electron microscope(SEM),particle size analysis,and Fourier transform infrared spectroscopy(FT-IR).The water vapor sorption and desorption of the formulated microcapsules was then experimen-tally studied using dynamic vapor sorption(DVS),with the results fitted to three kinds of adsorption kinetics models.In addition,the specific surface area(SSA)was also calculated based on BET theory;and the thermal performance was investigated by laser flash analysis(LFA).Experimental results show a change of 103%in mass of the microcapsule sample under 90%relative humidity(RH)at 30℃after water vapor sorption.The fitting of results indicates that the adsorption process is mainly governed by the intra-particle diffusion mechanism,followed by the pseudo-first-order adsorption process.In com-parison with most conventional pavement materials,it is found that the SSA of the formulated microcap-sules is much larger while the thermal conductivity is lower.The unique properties of the formulated SiO2-LiBr microcapsules have significant potential to take the edge off the urban heat island effect and reduce rutting when applied to water-retaining pavement materials.