Laser-Assisted Production of Carbon-Encapsulated Pt-Co Alloy Nanoparticles for Preferential Oxidation of Carbon Monoxide

Abstract

C-encapsulated highly pure PtxCoy alloy nanoparticles have been synthesized by an innovative one-step in-situ laser pyrolysis. The obtained X-ray diffraction pattern and transmission electron microscopy images correspond to PtxCoy alloy nanoparticles with average diameters of 2.4 nm and well-established crystalline structure. The synthesized PtxCoy/C catalyst containing 1.5 wt% of PtxCoy nanoparticles can achieve complete CO conversion in the temperature range 125–175°C working at weight hourly space velocities (WHSV) of 30 L h−1g−1. This study shows the first example of bimetallic nanoalloys synthesized by laser pyrolysis and paves the way for a wide variety of potential applications and metal combinations.

Laser Irradiation of Electrode Materials for Energy Storage and Conversion

“…The successfully fabricated structures include but are not Figures 7B-7D. [89][90][91][92][93][94] In addition to these achievements, the highly controlled heating enabled by laser irradiation permits intriguing heterostructures ll that have rarely been realized by other methods. A scalable graphene membrane with different carbonization degrees along the vertical direction made by elaborately controlling the lasing process (wavelength: 1,064 nm; CW) contributes to a Janus super-hydrophobic/super-hydrophilic structure.…”

“…(D) TEM image of the Pt-Co alloy-carbon composition synthesized by LAP. Reproduced with permission from Martinez et al91 Copyright 2018, Martinez, Malumbres, Lopez, Mallada, Hueso, and Santamaria. (E) TEM images of MOF nanorods-decorated graphene nanosheets.…”

Laser-driven direct synthesis of carbon nanodots and application as sensitizers for visible-light photocatalysis

“…Additionally, these methods display limited availability of control in stoichiometry requirements, making them very restricted processes for the synthesis of doped CNDs. Among the laser synthesis methods, laser pyrolysis represents an elegant alternative for the one-pot synthesis of a wide variety of carbonaceous materials, including amorphous carbon materials, fullerenes, carbon black, carbides or even graphene powders In the process of CO2 laser pyrolysis [45,[56][57][58][59][60] the reaction proceeds in-between the laser beam and the molecular flow of gaseous/vapors phase reactants. The resultant condensable products are generated at the interface.…”

“…Compared with other laser-driven approaches, the laser pyrolysis allows: (i) a well-defined interaction volume delimited by the radiation cross-section and the emerging gas flow; (ii) spatial uniformity of the reaction zone; (iii) highly localized and faster heating (leading to rapid nucleation) with faster quenching of the particles grow and (iv) versatile adjusting of process parameters to endow the nanoparticle with different composition and tailored properties. Although the use of a laser source represents an attractive alternative to conventional synthesis methods of CNDs (i. e. continuous production, potential scalability, low purification needs) [58][59][60]62], to date it has not been possible to retrieve them as freestanding and well-dispersed nanoparticles.…”

Synthesis of Silicon Nanoparticles in a Novel CO2 Laser Pyrolysis Reactor With an Elongated Reaction Zone

“…For instance, reports have exploited laser pyrolysis to generate silicon, 2-5 germanium, 6 silicon germanium alloy, 7,8 boron, 9 titanium oxide, 10 fullerene, 11 and iron oxide 12 nanoparticles. The versatility of the processing parameters permits various strategies for laser pyrolysis that can be employed to synthesize alloyed, 6,13 core-shell 14,15 and doped nanoparticles, 16,17 particularly by manipulating processing parameters or the con guration of the set-up.…”