A novel shape-stabilization strategy for phase change thermal energy storageElectronic supplementary information (ESI) available. See DOI: 10.1039/c9ta01496a

Solving the mismatch between the supply and demand of energy in energy storage techniques is critical. Here, we report a novel Lewis acid catalysis induced in situ phase change material (PCM) shape-stabilization strategy to fabricate hyper-crosslinked polystyrene (HCPS) encapsulated PCMs towards the goal of highly efficient thermal energy storage. A simultaneous cross-linking and encapsulation process, enabled by a powerful FeCl 3 catalyzed cross linking reaction, results in a highly efficient encapsulation rate. Thermal conductivity of the PCMs was enhanced by converting the cross-linking catalyst FeCl 3 to Fe 3 O 4 using a simple alkali treatment, by which 17% to 55% thermal conductivity enhancement was achieved compared with pure paraffin. Notably, waste polystyrene (PS) foam was demonstrated to be capable of being used as a starting material to support PCM, opening up a new avenue to utilize waste PS foam. A novel Lewis acid catalysis induced in situ phase change material (PCM) shape-stabilization strategy was developed to fabricate hyper-crosslinked polystyrene (HCPS) encapsulated PCMs towards highly efficient thermal energy storage.