Huangfu Geng, Ph.D. from Shanghai Jiaotong University, supervised by Professor Guo Yiping and Researcher Luo Haosu.
Research Interests: The correlation mechanisms between the multi-level structure of lead-free piezoelectric materials and their response to external fields.
Achievements: Huangfu Geng clarified the evolution of the lattice structure under thermal and electric fields in NBT-based crystals, revealing the mechanisms by which ferroelectric domain structures regulate polarization reversal. In KNN-based lead-free piezoelectric ceramics, synchronized adjustments of phase, domain, and lattice structures achieved significant electrostriction and performance comparable to commercial lead-based ceramics (large strain, low hysteresis, excellent fatigue resistance, and thermal stability) were obtained. The study provided a deep understanding of how material structure influences electrical properties, established a model for coupling directionally aligned defect dipoles with ferroelectric domains, and innovated a design theory for high-strain piezoelectric ceramics.