Phase Change Microcage for Multienergy Capture and Microwave Absorption

Advanced multifunctional composite phase change materials(PCMs)integrating dual-field excitative thermal storage and microwave absorption have been recently highlighted in cutting-edge applications.Herein,we designed a metal–organic framework(MOF)derived magnetic NiCo-modified open carbon microcage(NiCo@C)for the encapsulation of PCMs,which simultaneously achieve fast-response multienergy capture and bimode stealth functions:The NiCo@C/PW composite PCMs exhibited a relatively high phase change enthalpy of 130.39 J/g due to the high cavity volume of the NiCo@C microcage.Strikingly,the composite PCMs demonstrated excellent solar-thermal conversion,attributed to the local surface plasmon resonance effect of NiCo nanoparticles and full-spectrum absorption of high graphitized carbon microcage.Simultaneously,composite PCMs harvested high-efficiency magnetic-thermal conversion due to the Néel and Brownian relaxation effects of diffusely embedded magnetic NiCo nanoparticles.More importantly,this thermal energy storage system achieved high-performance microwave absorption with a minimum reflection loss(RL)of−38.1 dB at 11.8 GHz at only 2.35 mm thickness.Our designed all-in-one strategy created an innovative platform for constructing advanced multifunctional microwave-absorbing composite PCMs with thermal storage,dual-energy conversion,microwave absorption,and infrared stealth.

Power-to-gas technology in energy systems:current status and prospects of potential operation strategies

Regarded as a long-term, large capacity energy storage solution, commercialized power-to-gas(PtG) technology has attracted much research attention in recent years.PtG plants and natural gas-fired power plants can form a close loop between an electric power system and a natural gas network. An interconnected multi-energy system is believed to be a solution to the future efficient and environmental friendly energy systems. However, some crucial issues require in-depth analysis before PtG plants can be economically implemented. This paper discusses current development status and potential application of PtG plants in the future interconnected multi-energy systems, and further analyzes the costs and benefits of PtG plants in different application scenarios. In general, the PtG plants are not economical efficient based on current technologies and costs. But the situation is likely to change with the development of PtG technologies and interconnected operation of gas-electricity energy system.