title: Scalable economic extracellular synthesis of CdS nanostructured particles by a non-pathogenic thermophile.
abstract: We report microbially facilitated synthesis of cadmium sulfide (CdS) nanostructured particles (NP) using anaerobic, metal-reducing Thermoanaerobacter sp. The extracellular CdS crystallites were <10 nm in size with yields of ~3 g/L of growth medium/month with demonstrated reproducibility and scalability up to 24 L. During synthesis, Thermoanaerobacter cultures reduced thiosulfate and sulfite salts to H₂S, which reacted with Cd²⁺ cations to produce thermodynamically favored NP in a single step at 65 °C with catalytic nucleation on the cell surfaces. Photoluminescence (PL) analysis of dry CdS NP revealed an exciton-dominated PL peak at 440 nm, having a narrow full width at half maximum of 10 nm. A PL spectrum of CdS NP produced by dissimilatory sulfur reducing bacteria was dominated by features associated with radiative exciton relaxation at the surface. High reproducibility of CdS NP PL features important for scale-up conditions was confirmed from test tubes to 24 L batches at a small fraction of the manufacturing cost associated with conventional inorganic NP production processes.
authors.affiliation: Biosciences Division, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, 37831, USA, moonj@ornl.gov.
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Moon
authors.forename: Ilia N
authors.initials: IN
authors.lastname: Ivanov
authors.forename: Chad E
authors.initials: CE
authors.lastname: Duty
authors.forename: Lonnie J
authors.initials: LJ
authors.lastname: Love
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Rondinone
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Yi-Liang
authors.initials: YL
authors.lastname: Li
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Madden
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Mosher
authors.forename: Michael Z
authors.initials: MZ
authors.lastname: Hu
authors.forename: Anil K
authors.initials: AK
authors.lastname: Suresh
authors.forename: Claudia J
authors.initials: CJ
authors.lastname: Rawn
authors.forename: Hyunsung
authors.initials: H
authors.lastname: Jung
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lauf
authors.forename: Tommy J
authors.initials: TJ
authors.lastname: Phelps
mesh_terms: D018533:Biomass; D001709:Biotechnology; D019187:Cadmium Compounds / Q000737:chemistry / Q000191:economics / Q000378:metabolism*; D002384:Catalysis; D003460:Crystallization; D003470:Culture Media; D005110:Extracellular Space / Q000378:metabolism*; D005285:Fermentation; D008163:Luminescent Measurements; D049329:Nanostructures / Q000737:chemistry* / Q000191:economics*; D036103:Nanotechnology; D015203:Reproducibility of Results; D013057:Spectrum Analysis; D013440:Sulfides / Q000737:chemistry / Q000191:economics / Q000378:metabolism*; D013447:Sulfites / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism; D046968:Thermoanaerobacter / Q000378:metabolism*; D013885:Thiosulfates / Q000378:metabolism; D013997:Time Factors
chemical_list: D019187:Cadmium Compounds; D003470:Culture Media; D013440:Sulfides; D013447:Sulfites; D013885:Thiosulfates; C034939:cadmium sulfide; D013455:Sulfur; C042345:hydrogen sulfite