Terminal group engineering of Ti₃C₂T_x MXene on thermal emitter performance

Area of Science:

• Materials Science
• Nanotechnology
• Optics

Background:

• MXenes, particularly Ti3C2Tx, are advanced materials with tunable properties for nanophotonics.
• Thermal emitters are crucial for energy harvesting and radiative cooling, requiring precise control over emissivity.

Purpose of the Study:

• To investigate the influence of Ti3C2Tx MXene terminal groups (-F, -O-, -OH) on the performance of a VO2/SiO2/Ti3C2Tx planar thermal emitter.
• To quantify the effect of different MXene surface terminations on differential emissivity (Δε).

Main Methods:

• Fabrication of planar thermal emitters with a VO2/SiO2/Ti3C2Tx structure using four variants of Ti3C2Tx MXene.
• Characterization of spectral properties across the 2-20 µm range.
• Analysis of differential emissivity (Δε) based on MXene terminal group composition.

Main Results:

• The VO2 phase change material ensured a constant hysteresis loop threshold temperature across all MXene types.
• Differential emissivity (Δε) varied significantly with MXene terminal group composition.
• VO2/SiO2/Ti3C2F2 exhibited the highest Δε (0.42), while VO2/SiO2/Ti3C2(OH)2 showed the lowest (0.33).

Conclusions:

• MXene terminal group engineering offers a pathway to control and tailor thermal emission.
• These findings are foundational for developing tunable photonic devices for energy harvesting, thermophotovoltaics, and radiative cooling.
• Precise thermal control through MXene modification supports next-generation energy management systems.