Surface-engineered diamond/liquid metal composites with significantly enhanced thermal conductivity for advanced thermal interface materials

Air annealing and TiC coating engineer diamond surfaces for enhanced interfacial bonding. • Surface-treated Diamond/GaInSn composites achieve thermal conductivity up to 111.6 W m -1 K −1 . • The study reveals a trade-off between bulk conductivity and practical interfacial thermal resistance. • Engineered composites demonstrate superior cooling performance in photovoltaic cell applications. The ever-increasing power density and integration level of modern electronic devices, driven by advances in artificial intelligence and energy technologies, impose stringent demands on thermal management. Conventional cooling strategies often fail to cope with the escalating heat flux, highlighting the urgent need for high-performance thermal interface materials (TIMs). Here, we employ two surface engineering strategies, air annealing and titanium carbide (TiC) coating, to tailor the interfacial properties of micrometer-sized diamond particles. The modified diamonds are then embedded in a gallium-based liquid metal (LM) matrix, yielding composite TIMs with enhanced thermal conductivity and robust interfacial stability. The resulting composites exhibit remarkable thermal conductivities, reaching of up to 111.6 W m −1 K −1 for the air-annealed and 102.4 W m −1 K −1 for the TiC-coated sample. The surface treatments markedly improved the interfacial contact continuity and chemical environment between diamond and liquid metal, thereby mitigating LM leakage and enhancing the overall mechanical integrity of the composites. When integrated into high-power electronic devices, such as photovoltaic cells, these engineered TIMs demonstrate efficient heat dissipation and markedly suppress the operating temperature of the heat source. This work provides a promising material solution for thermal management in high-power electronics and advances the practical application of liquid metal-based composites. In this study, composite thermal interface materials (TIMs) were fabricated using diamond and GaInSn liquid metal as raw materials via a facile surface treatment process, enabling efficient thermal management of electronic devices. Air annealing and titanium carbide (TiC) coating treatments modified the wettability and interfacial bonding strength between reinforced diamond and liquid metal, thereby effectively enhancing the thermal conductivity of the composites. Download: Download high-res image (149KB) Download: Download full-size image