Novel microencapsulated phase change materials with calcium carbonate shell and paraffin-based binary cores were prepared via self-assembly method. The phase change temperature of the microcapsules could be adjusted from 25 to 50 degrees C by changing the weight ratio of binary cores. FTIR confirmed that the calcium carbonate shell material was successfully fabricated upon the paraffin-based binary cores. SEM and TEM demonstrated the microcapsules had a spherical morphology and compact surfaces with diameter ranging from 1 to 5 gm. DSC results indicated that the binary cores content of microcapsules was in a range of 55.7-59.4%. TGA showed that mass loss of the microcapsules was between 5% and 28% when heated to 400 degrees C. Infrared imager exhibited the binary cores microcapsules possessed excellent temperature-regulated properties. Besides, the thermal conductivity of the microcapsules was significantly enhanced due to the presence of highly thermally conductive calcium carbonate shell. Since the low costs and outstanding properties, it exhibits a good prospect in the thermal energy storage and thermal management. (C) 2016 Elsevier Ltd. All rights reserved.