Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Investigation of factors affecting the synthesis of nano-cadmium sulfide by pulsed laser ablation in liquid environment
Graphical abstract
Introduction
In the last few decades, research on semiconductor materials in nanoscale had been increased enormously and has been extremely attractive and of interest to several fields which include optoelectronic devices, solid-state lasers and solar cells [1], [2], [3]. Among semiconductor materials, cadmium sulfide (CdS) nanostructures in the form of quantum dots, nanowires, and thin films are widely investigated by many researchers [4]. For these applications it is important to synthesize nanoparticles with the adequate size distribution, morphology and crystallinity. There are different techniques for producing materials in the nanoscale such as pulsed laser deposition, flame metal combustion, chemical reduction, photo-reduction, electrochemical reduction, solvothermal, electrolysis, microwave-induced, sono-electrochemical, aerosol flow reactor, photochemical reduction, chemical fluid deposition, spray pyrolysis, and spark discharge [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20]. Many of these techniques use precursors and solvents, or imply chemical reactions which can contaminate the obtained nanoparticles. Pulsed laser ablation of solids in liquid environment (PLAL), one of these techniques, enables obtaining nanoparticles with no need of chemical precursors. Its simplicity together with the advantage of producing nanoparticles with small size, narrow distribution and weak agglomeration make it suitable for metal nanoparticle fabrication. This alternative physical nanofabrication method opened new routes for material processing based on the pulsed laser ablation of solids in various liquids. It could be used to produce a wide range of novel materials, such as nano-diamond and related nanocrystals, metallic nanocrystals, nanocrystal alloys, and metal oxides [21], [22], [23], [24].
In the PLAL method, three main steps contribute to form nanoparticles from a target immersed in liquid. Only in a short period of time, typically about a few microseconds, all these steps take place and nanoparticles are synthesized. Firstly, laser pulse heats up the target surface to the boiling point, and thus, plasma plume containing vapor atoms of target is generated. Then, plasma expands adiabatically; and finally, nanoparticles are generated when condensation occurs [24]. During the condensation step, nucleation takes place, and the fine nuclei either collide and stick to each other or precipitate new materials on them which result in growth.
The efficient size control approaches employ variations of physical parameters of laser radiation, such as laser pulse energy, repetition rates, laser wavelength, focal spot size and focusing conditions [25], [26], [27]. Therefore, there are number of factors that should be taken into account during the laser–matter interaction in liquid environment. In this paper, CdS nanostructures were investigated under different promising factors, focusing conditions and ablation mechanisms, that help us to optimize laser parameters and focus on conditions to produce and control the shape/size of the desired nanostructures.
Section snippets
Materials
The materials used are Cadmium chloride hemipentahydrate (CdCl2·xH2O) of M.W. 228.35, specification assay 95%, from S.d. Fine-Chem. Ltd.; and Sulfur (S) of A.W. 32.97 from S.d. Fine-Chem. Ltd., Cadmium Sulfide (CdS) of M.W. 144.48 from S.d. Fine-Chem. Ltd. All chemicals were of analytical grade and used without further purification.
Experiment
CdS nanostructures were synthesized by a Nd:YAG laser which is a Q-switched solid state laser, which emits its fundamental line (λ) at 1064 nm producing a pulsed 7
Optimization of PLAL process
The parameters of the PLAL-experiment were tightly controlled during and after the ablation process. These parameters were found to play a crucial role in controlling the shape and size of the produced nanostructures. Hence, it is worthwhile to optimize the PLAL process which can be divided into:
- i)
Adjustment of the PLAL system
- ii)
Adjustment of the ablated materials and its medium
Conclusion
By using the information of absorption from the UV–visible spectra, there are a number of factors affected by the synthesis of materials (e.g., CdS) in the nanoscale using the PLAL technique studied: Effect of the different types of media (distilled water, deionized water or tap water), effect of different concentrations of solution (Na2S solution), effect of sintering of the target, and effect of the position of the material surface with respect to the focusing of the pulsed laser inside the
Acknowledgments
We thank the Laser Technology Unit (LTU), Center of Excellence for Advanced Sciences (CEAS) in National Research Center (NRC) of Egypt for funding.
References (37)
- et al.
Mater. Sci. Eng. C
(2003) - et al.
Appl. Surf. Sci.
(2007) - et al.
Powder Technol.
(2010) - et al.
Mater. Lett.
(2006) - et al.
Thin Solid Films
(2006) - et al.
Chem. Phys. Lett.
(2006) - et al.
J. Colloid Interface Sci.
(2003) - et al.
Sol. State Chem.
(2008) - et al.
Chem. Phys. Lett.
(2010) Prog. Mater. Sci.
(2007)
Appl. Surf. Sci.
Appl. Surf. Sci.
J. Colloid Interface Sci.
Colloids Surf. A Physicochem. Eng. Asp.
Mater. Res. Bull.
Synth. Met.
Appl. Phys. Lett.
Appl. Phys. Lett.
Cited by (78)
Characteristics and antibacterial properties of carbon nanoparticles synthesized by the pulsed laser ablation method in various liquid media
2024, Environmental Nanotechnology, Monitoring and ManagementPhysicochemical robustness of pulse laser ablated silver-copper nanocomposoites against varied bacterial strains
2023, Optics and Laser TechnologyTemperature controlled morphology transformation during aging of colloidal copper nanoparticles produced by laser ablation in water
2023, Materials Today CommunicationsSpinel lithium titanate anode/polyether sulfone nanocomposite synthesized by pulsed laser ablation method for optoelectronic applications
2023, Journal of Saudi Chemical SocietyCustomization of structure, morphology and optical characteristics of silver and copper nanoparticles: Role of laser fluence tuning
2023, Applied Surface ScienceCitation Excerpt :Subsequently, the expanding cavitation bubbles are created owing to the energy transfer from the hot plasma into the immersion liquid, releasing several tiny fragments from the target material. Thereafter, the generated cavitation bubbles support the nucleation and growth process [29–31]. Hence, some of the material can be ruptured and dispersed away from the bulk target as tiny droplets, vapors or even expanding plasma plume during a laser ablation process.
Synthesis and characterization of Au:CdO nanoparticles using laser ablation in liquid as gases sensors
2022, Optics and Laser Technology