Molybdenum Blues with Tunable Light Absorption Synthesized by Femtosecond Laser Irradiation of Molybdenum Trioxide in Water/Ethanol Mixtures

Abstract

Molybdenum blues (MBs) have attracted increasing attention due to their tunable structures and properties, which make them applicable in numerous fields. In this work, a novel strategy to synthesize MB nanorings by irradiating MoO3 suspended in water/ethanol mixtures with intense femtosecond laser pulses is demonstrated. It is found that the MoO3 can be dissolved in the water during laser irradiation to form molybdic acid, which provides an acidic environment for the formation of MB. Concentrations of ethanol as low as 1% result in the formation of MB and by adjusting the concentration of ethanol in the solvent, the absorption band can be tuned due to the modification of MoVOMoVI entities. The MB synthesized in 30% ethanol appears the darkest blue and assembly of vesicles 115 nm in size is observed. At high concentrations of ethanol (>70%), HXMoO3 and MoO3‐X are preferentially formed instead of MB. The photothermal conversion efficiency of the MBs synthesized in 1% and 30% ethanol is above 40%.

Defect‐Rich MoSe2 2H/1T Hybrid Nanoparticles Prepared from Femtosecond Laser Ablation in Liquid and Their Enhanced Photothermal Conversion Efficiencies

“…Preparation of MoSe 2 Nanoparticles: The setup of laser ablation of MoSe 2 in liquid was similar to that used in the previous reports. [59,73] MoSe 2 powder (99.9%, 325 mesh, Thermo Scientific) was added to IPA (99.9%, HPLC, Sigma-Aldrich) with a concentration of 0.28 mg mL −1 . After 20 min of bath sonication to break agglomerates, 4 mL of the suspension sample was transferred to a small vial for laser ablation.…”

“…The PTCEs of the nanoparticles were evaluated using a custom-built setup, as described in the previous work. [59,73] For the PTCE measurements, the concentrations of all the samples were 0.2 mg mL −1 . 1 mL of each sample was transferred to a quartz cuvette with a path length of 1 cm, and then illuminated by an 808 nm continuous wave laser (BWF1-B&W Tek) for 10 min followed by 10 min of cooling.…”

PEGylated MoSe2 Nanomaterials with Limited Oxidation via Femtosecond Laser Ablation for Photothermal Therapy

“…The absorbance spectra of the nanomaterials were measured with a UV–vis–NIR spectrometer (Lambda 1050, PerkinElmer). The PTCEs of the nanoparticles were evaluated using a custom-built setup, as described in the previous work. ,, The concentration of MoSe 2 in all of the samples was 1.1 mM. 1 mL of each sample was transferred to a quartz cuvette with a path length of 1 cm and then illuminated by an 808 nm continuous-wave laser (BWF1-B&W Tek) for 10 min followed by cooling for 10 min.…”