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Dilution refrigerators are widely used in the fields of condensed matter physics and quantum technology. The condensation-driven dilution refrigerator uses a condenser operating at temperatures below the Still to liquefy the 3He vapor and achieve the circulation of 3He, which has the advantages of compact structure, lightweight, low cost, and low vibration. The published research primarily focuses on the system architecture and performance, and the research and analysis on the thermodynamic cycle are still incomplete. In this paper, the condensation-driven dilution refrigeration cycle has been clarified as a thermally driven refrigeration cycle, and the thermodynamic performances including the figure of merit and thermodynamic perfectibility are investigated. Optimizations have been made to the key components of the previous prototype, and the lowest no-load temperature of 68 mK and a cooling power of 4 μW at 100 mK were achieved. Compared with the previous prototype, the thermodynamic perfectibility of the system increased from 7.63% to 17.83%. The impact of the Still heating strategies on the system was analyzed, and a start-up strategy was proposed to speed up the cooldown process. [ABSTRACT FROM AUTHOR]

To overcome the overheating phenomena of electronic devices and energy components, developing advanced energy‐free cooling coatings with promising radiative property seem an effective and energy‐saving way. However, the further application of these coatings is greatly limited by their sustainability because of their fragile and easy contamination. Herein, it is reported that a bioinspired radiative cooling coating (BRCC) displayed sustainably efficient heat dissipation by the combination of high emittance and robust self‐cleaning property. With the hierarchical porous structure constructed by multiwalled carbon nanotubes (MWCNTs), modified SiO2 and fluorosilicone (FSi) resin, the involvement of the BRCC improves the cooling performance by increasing ≈25% total heat transfer coefficient. During the abrasion and soiling tests, the BRCC‐coated Al alloy heat sink always displays stable radiative cooling performance. Moreover, the simulation and experimental results both revealed that reducing surface coverage of BRCC (≈80.9%) can still keep highly cooling efficiency, leading to a cost‐effective avenue. Therefore, this study may guide the design and fabrication of advanced radiative cooling coating. [ABSTRACT FROM AUTHOR]

To overcome the overheating phenomena of electronic devices and energy components, developing advanced energy-free cooling coatings with promising radiative property seem an effective and energy-saving way. However, the further application of these coatings is greatly limited by their sustainability because of their fragile and easy contamination. Herein, it is reported that a bioinspired radiative cooling coating (BRCC) displayed sustainably efficient heat dissipation by the combination of high emittance and robust self-cleaning property. With the hierarchical porous structure constructed by multiwalled carbon nanotubes (MWCNTs), modified SiO 2 and fluorosilicone (FSi) resin, the involvement of the BRCC improves the cooling performance by increasing ≈25% total heat transfer coefficient. During the abrasion and soiling tests, the BRCC-coated Al alloy heat sink always displays stable radiative cooling performance. Moreover, the simulation and experimental results both revealed that reducing surface coverage of BRCC (≈80.9%) can still keep highly cooling efficiency, leading to a cost-effective avenue. Therefore, this study may guide the design and fabrication of advanced radiative cooling coating., Competing Interests: The authors declare no conflicts of interest. Jiang Lei is a member of the Exploration editorial board., (© 2023 The Authors. Exploration published by Henan University and John Wiley & Sons Australia, Ltd.)