Hexagonal boron nitride nanosheets doped pyroelectric ceramic composite for high-performance thermal energy harvesting

Recently, recycling energy from wasted heat with pyroelectric materials has received significant attention. However, pyroelectric energy harvesters generally suffer from a low energy efficiency due to the low rates of heat transfer. Here, we report high-performance thermal energy harvesting using novel hybrid pyroelectric ceramics with greatly improved heat transfer and rate of temperature changes. This is achieved by evenly dispersing 0.1 wt% hexagonal boron nitride (hBN) nanosheets into a Pb[(Mn _1/3 Nb _2/3 ) _1/2 (Mn _1/3 Sb _2/3 ) _1/2 ] _0.04 (Zr _0.95 Ti _0.05 ) _0.96 O ₃ (lead magnesium niobate-lead antimony-manganese-lead zirconate titanate: PMN-PMS-PZT) ceramic matrix. Due to the vibrations of whole chain and phonon scattering, heat transfer through the hybrid crystalline chain is more efficient than that of unfilled PMN-PMS-PZT. It is demonstrated that the harvested power was increased by up to 65.6%. This work paved an efficient and cost-effective way to largely improve the traditional pyroelectric ceramic for thermal energy harvesting.