Enhanced Humidity Stability of (Li,K,Na)NbO sub(3)-Based Lead-Free Piezoelectric Ceramics by Adding B sub(2)O sub(3)

5wt%B sub(2)O sub(3)-doped (Li,K,Na)NbO sub(3) (abbreviated as LKNN-B5)-based lead-free piezoelectric ceramics were prepared via solid state synthesis. The electrical humidity sensitive properties of LKNN-B5 ceramics were examined and compared with pure LKNN ceramics. The results revealed thatB sub(2)O sub(3) doping enhanced electrical stability of LKNN-based ceramics in relative humidity (RH) range of 33-95%. The capacitance change was suppressed from 105% down to 43% when doped with B sub(2)O sub(3). The average absorption time was reduced from 5.5 min to 1.5 min, and desorption time decreased from 8.5 min to 2.0 min. The enhanced electrical stability of LKNN-B5 series was attributed to the dense structure induced by liquid phase sintering.