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High-yielded Bi2Te3 hexagonal nanoplates with average size from 650.8 to 736.5 nm and nanoscaled Bi2Te3 nanoparticles with a size of 91.4+2.2 nm were fabricated via facile solution methods.The morphology of Bi2Te3 nanoplates are determined by the molecular weight of the added PVP.The hexagonal nanoplates with high yield were obtained in the presence of PVP with molecular weight of 40000-45000.The average size and size distribution of Bi2Te3 nanoplates can be slightly varied by controlling concentration of PVP.The high-yielded Bi2Te3 nanoplates and nanoscaled Bi2Te3 both exhibit characteristics of saturable absorption,identified by open-aperture Z-scan technique.The Bi2Te3 nanoplates with large saturation intensity of 4.6 GW/cm2 and high modulation depth of 45.95%generated a stable passively Q-switched fiber laser pulse at 1.5 μm.In comparison with recently reported Q-switched fiber lasers utilizing exfoliated Bi2Te3 nanosheets,our passive Q-switching operations could be conducted at a relatively low threshold power of 30.2 mW and be tunable in a wide range of repetition rate from 7.5 to 68.0 lkHz.Additionally,the nanoscaled Bi2Te3 show higher saturation intensity of 18.9 GW/cm2,suggesting that it could potentially be applied in large-energy laser pulses.