Selective anisotropic growth of Bi2S3 nanoparticles with adjustable optical properties. Issue 5 (17th January 2023)

• Record Type: Journal Article
• Authors: Escoda-Torroella, Mariona; Moya, Carlos; Ruiz-Torres, José A.; Fraile Rodríguez, Arantxa; Labarta, Amílcar; Batlle, Xavier
• Is Part Of: Physical chemistry chemical physics. Volume 25:Issue 5(2023)
• Page Start: 3900
• Page End: 3911
• Publication Date: 2023-01-17
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d2cp05437j
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Controlled synthesis and functionalization of elongated Bi2 S3 NPs with tunable optical properties. Abstract : We report on the controlled synthesis and functionalization in two steps of elongated Bi2 S3 nanoparticles within a wide range of sizes. First, we show the effect of the temperature and reaction time on the synthesis of two series of nanoparticles by the reaction of thioacetamide with bismuth(iii ) neodecanoate in the presence of organic surfactants. At 105 °C and long reaction times, nanoneedles of about 45 nm in length containing larger crystallites are obtained, while highly crystalline nanorods of about 30 nm in length are dominant at 165 °C, regardless of the reaction time. The optical properties of both types of nanoparticles show an enhancement of the band gap compared to bulk Bi2 S3 . This is likely to arise from quantum confinement effects caused by the small particle dimensions relative to the typical exciton size, together with an increase in near-infrared absorption due to the anisotropic particle shape. Second, a ligand exchange approach has been developed to transfer the Bi2 S3 nanoparticles to aqueous solutions by grafting dimercaptosuccinic acid onto the surface of the particles. The as-prepared coated nanoparticles show good stability in water, in a wide biological pH range, and in phosphate-buffered saline solutions. Overall, this work highlights the controlled design at all levels – from the inorganic core to the organic surface coating – of elongated Bi2 S3 nanoparticles, leading to a tunable optical response by tuning their morphology and size.