Magnetically-accelerated photo-thermal conversion and energy storage based on bionic porous nanoparticles

Lei Shi,Yanwei Hu,Daili Feng,Yurong He,Yuying Yan

doi:10.1016/j.solmat.2020.110681

Abstract

Recently, the technology of mixing phase change materials with high thermal conductivity fillers was developed, which has allowed thermal energy storage to be implemented in a wide range of industrial technologies and processes. In the present study, a hierarchical bionic porous nano-composite was prepared, which efficiently merged the nanomaterial characteristics of magnetism and high thermal conductivity in order to form a magnetically-accelerated solar-thermal energy storage method. The morphology and thermo-physical properties of materials were analysed. The experimental outcomes of phase change heat transfer demonstrated that the maximum storage efficiency increases by 102.7% when the hierarchical bionic porous structure is used, and a further 27.1% improvement can be achieved with the magnetic field. At the same time, the heat transfer process of energy storage in hierarchical porous composites under external physical fields is explained by simulation. Therefore, this magnetically-accelerated method demonstrated the superior solar-thermal energy storage characteristics within a hierarchical bionic porous structure which is particularly beneficial for the utilisation of solar direct absorption collectors and energy storage technology.

Highlights

The world’s energy consumption has increased, due to the drastic development of human society which has caused global warming and environmental pollution [1,2]
The BET surface area was measured to be as high as 184.6 m2 g–1 (MT), compared to the 146.2 m2 g–1 MF nanoparticles, which were the result of their hierarchical pores within the nano-structure, visible in the desorption-adsorption isotherms and the distributions of pores
Phase change materials with hierarchical bionic porous were formed with the help of a two-step method with paraffin wax and porous magnetic nanoparticles

Summary

Introduction

The world’s energy consumption has increased, due to the drastic development of human society which has caused global warming and environmental pollution [1,2]. The hierarchical porous material is considered as a developing type of porous material which possesses a variety of levels of structure and porosity [16] This helps in presenting the unique scale benefits from micro pores to a macro level [17]. The hierarchical porous architecture causes degradation to the structure of energy shortage and fast heat transfer incurred by volume expansion during the charge cycle process [20]. Very little research has been conducted on solar-thermal PCM systems on the basis of nanofluid PCMs, allowing separate expansion of the conversion of solar-thermal efficiency after applying the external physical fields, such as magnetic, sound, electric field [39,40,41], let alone studying the heat transfer process of solar-thermal storage and energy conversion in hierarchically porous structures under external physical fields. The heat transfer process of photo-thermal energy conversion and storage in hierarchically porous materials under an external physical field was verified by simulation

Experimental research

Results and discussion

Conclusion