“…For example, Bi 4 Ti 3 O 12 (referred to as BiT) is the first choice of piezoelectric material for high temperature piezoelectric vibration sensor (˃˃ 500°C) in the world at present, which is widely used in aerospace, nuclear energy and other fields to monitor the vibration of key equipment under high temperature and harsh environment ( Zhang and Yu, 2011 ). The crystal structure of BLSFs is formed by pseudo-perovskite blocks ( A m-1 B m O 3m+1 ) 2- and bismuth layers (Bi 2 O 2 ) 2+ in regular alternate arrangement ( Wong et al, 2017 ), where A is a mono-, di-, tri-valent (Na + , Ba 2+ , Sr 2+ , Ca 2+ , Bi 3+ , La 3+ , etc.) cations allowing 12-coordination, B is a six- coordination transition metal (Ti 4+ , Ta 5+ , Nb 5+ , Mo 6+ , W 6+ , Co 3+ , etc.)…”