## 1 Introduction
The development of liquid immersion cooling technology for electronic devices has roughly experienced the exploration period (before 1992), the research period (1992-2016) and the small-scale application period (2016-present) [20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42], shown in Figure 1. According to MarketsandMarkets, the market is expected to grow from USD 244 million in 2021 to USD 1710 million by 2030, at a GACR of 24.2% from 2022 to 2030 [25]. Many companies such as Huawei, Lenovo, Inspur, Facebook, Microsoft, etc., have also developed immersion liquid-cooled high-density servers. Before liquid immersion cooling technology steps forward to overall large-scale deployments, there are lots of key technologies to be resolved, for example, product development, the formulation of unified standards, the screening of liquid coolants, etc. [38]. According to whether the liquid coolants undergo a phase change, liquid immersion cooling can be divided into single-phase liquid immersion cooling and two-phase liquid immersion cooling. Although single-phase systems are more attractive for some enterprises than two-phase systems by considering the difficulty of system design and the balance between the cost and benefits [39], two-phase liquid immersion cooling systems are receiving more and more attention with the rapid increase in heat fluxes of power devices, and it is urgent to overcome the key technologies and develop an efficient two-phase immersion cooling system due to the growing heat dissipation demand. For the marketization of two-phase liquid immersion cooling systems, the screening of liquid coolants is one of the most important technologies. The coolants used in liquid immersion cooling systems are in direct contact with electronic components; so, they must have good compatibility with the materials of all components under long-term operation, excellent electrical insulation to ensure the safety of the electronics, a low dielectric constant and a dielectric loss factor to avoid signal interference. At the same time, the coolants must be environmentally friendly, non-toxic and non-flammable. Because the generation and evolution of bubbles is essential for two-phase immersion cooling technology, the related thermodynamic properties have a great impact on the heat dissipation capacity of the cooling technology, including the boiling point, thermal conductivity, viscosity, surface tension and latent heat of vaporization, etc. For example, the greater the thermal conductivity of the coolant, the smaller the heat loss (thermal resistance) along the heat transfer direction, which is more conducive to boiling heat transfer. Surface tension greatly affects the size of the boiling bubbles and the wettability of the coolant to the surface of the heat source. According to bubble dynamics [43; 44], a smaller surface tension always means a smaller diameter of the separation bubbles, and the shorter the time from generating to detachment from the heat surface of the bubbles, the faster the surrounding liquid can wet the heat surface and the more intense the boiling heat transfer. The viscosity of the coolant is also an important property that greatly affects the flow of the coolant and the movement of the bubbles. Generally, a lower viscosity is more conducive to reducing the resistance of the flow of coolants and the movement of bubbles, which is more conducive to the boiling heat transfer. The higher the latent heat of vaporization, the greater the ability for a given mass of coolant to taking away the heat  
Figure 1: The development of liquid immersion cooling for electronic devices [20; 21; 22; 23; 24; 25]. generated by the electronic devices. Therefore, to determine whether a coolant is suitable for a two-phase immersion cooling system, it is essential to study the key thermodynamic properties first. However, for a new coolant (or a new electronic fluoride liquid), it is always difficult and quite costly to obtain the abovementioned properties comprehensively by experimentation.