Controlled Growth of Graphene-Skinned Al₂O₃ Powders by Fluidized Bed-Chemical Vapor Deposition for Heat Dissipation

The growing demand for high-performance chips, driven by digitalization and intelligence advancements, is accompanied by rising power consumption, highlighting the critical need for efficient thermal management in electronics. Graphene and its composites, characterized by their exceptional thermal conductivity, hold a distinctive position in this domain. The controlled synthesis of high-quality multilayer graphene composites, however, remains a significant challenge, hindering the full utilization of graphene's exceptional thermal conductivity. In this research, we present a breakthrough synthesis strategy for graphene-skinned alumina (Al₂O₃) composites via fluidized bed-chemical vapor deposition (FB-CVD), constructing a continuous graphene skin with high crystallinity with superior reproducibility between batches. This unique structure enhances thermal conductivity and overall performance by leveraging graphene's superior surface characteristics, interlayer thermal properties, and strong phonon coupling with Al₂O₃. The heat flow within the graphene skin surpasses that within the Al₂O₃ powders by more than an order of magnitude, establishing a comprehensive heat transfer network in the composite system. The derived thermal interface materials achieve an exceptional thermal conductivity of 6.44 W·m^-1·K^-1 and reduce hotspot temperatures in micro-LEDs by 17.7 °C. This research established a scalable platform for the synthesis of graphene-skinned ceramic composites, representing a paradigm shift in thermal management strategies for next-generation nanoelectronics.