title: Controllable biosynthesis of high-purity lead-sulfide (PbS) nanocrystals by regulating the concentration of polyethylene glycol in microbial system.
abstract: We demonstrated a simple biological method to explore the controllable synthesize of high-purity PbS nanocrystals by regulating the concentration of polyethylene glycol in microbial system. The biogenic H2S produced via the reduction of sulfate precipitated Pb2+ions as sulfide extracellularly, and the optimal removal rate of Pb2+ions is up to 96.7 % in 2 weeks. The characterization results showed that PbS nanocuboids with a particle size 50 × 50 × 100 nm obtained from Case A with 4 mM polyethylene glycol as a dispersant, and can completely degrade methylene blue from solution within 20 h; PbS nanosheets with a thickness size ca. 10 nm attained from Case B with 12 mM polyethylene glycol, and it can degrade 61.6 % dye within 24 h; PbS nanoparticles with a uniform diameter of ca. 60 nm formed from Case C with 20 mM polyethylene glycol, only degrade 14.1 % dye within 24 h. It is interesting that the factor affecting their catalytic activities is not the specific surface area, but the number of [200] crystal plane. This work not only displayed a simple synthetic method to control the morphology of PbS nanocrystals in microbial system, but also provided an economic and environmentally friendly approach for resourceful treatment and efficient bioremediation of wastewater-containing heavy metal.
authors.affiliation: School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Yue
authors.affiliation: School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
authors.forename: Shiyue
authors.initials: S
authors.lastname: Qi
authors.affiliation: School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China. xinbaoping@bit.edu.cn.
authors.forename: Baoping
authors.initials: B
authors.lastname: Xin
mesh_terms: D000068536:Bacillota / Q000254:growth & development*; D007854:Lead / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000494:pharmacology*; D013440:Sulfides / Q000737:chemistry*
chemical_list: D013440:Sulfides; C018391:lead sulfide; D007854:Lead; D011092:Polyethylene Glycols; C000595209:polyethylene glycol 1000
keywords: Biosynthesis; Nanocrystals; PbS; Photocatalysis; Polyethylene glycol