▎ 摘　　要

NOVELTY - A piezoelectric material comprises structure (a) of alternate laminate of layer of organic onium and layer of inorganic phase, and composite (b) containing aggregate particles of graphene structure and perovskite structure having average particle size of 200 nm or less. USE - Piezoelectric material is used for ultrasonic transducer for medical ultrasonograph and non-destructive ultrasonic inspection instrument (all claimed). Can also be used for sensor and actuator. ADVANTAGE - The material has excellent piezoelectric property in broader band region. DETAILED DESCRIPTION - A piezoelectric material comprises structure (a) of alternate laminate of layer of organic onium and layer of inorganic phase and composite (b) containing aggregate particles of graphene structure and perovskite structure having average particle size of 200 nm or less. The structure (a) is of formula: G2MX4 (I). G=organo onium; M=group IV element or transition metal;and X=Cl, Br or I.