Spinodal Decomposition in Tellurite‐Based Glasses Induced by Excimer Laser Irradiation

Abstract

Tellurite‐based glasses in the TeO2–K3Li2Nb5O15, TeO2–Ba5Li2Ti2Nb8O30, and V2Te2O9 were fabricated by the conventional melt‐quenching technique. Amorphous and glassy characteristics of the as‐quenched samples were established via the X‐ray powder diffraction technique and differential thermal analysis, respectively. The as‐quenched samples were irradiated by an excimer laser (248 nm). The effect of laser power, duration of irradiation, and the frequency of the laser pulses on the surface features of the above glasses were studied. The optical microscopic studies carried out on the above systems revealed the presence of quasi‐periodic and periodic structures on their surfaces. The local compositional variations of these structures were confirmed by back‐scattered electron imaging using scanning electron microscope accompanied by energy‐dispersive X‐ray analysis. These results were convincing enough to state that the glasses in the present investigations had undergone spinodal decomposition on laser irradiation. The incidence of the interconnected texture of two different phases was observed owing to the quenching effect produced by the heating and cooling cycle of the successive laser pulses. Ring‐ and line‐shaped patterns were also observed, respectively, when the pulse frequency of the laser and the duration of irradiation were increased.

Symmetry constraints during the development of anisotropic spinodal patterns

“…Spinodal decomposition is a well-known phase-separation phenomenon of disordered media that produce coherent nanoscale intergrowths, commonly used to improve the physical properties of diverse materials, including metallic alloys 1 2 , thermoelectric materials 3 4 , magnetic materials 5 , liquid crystals 6 7 , polymers 8 9 10 and glasses 11 12 . Phase separation by spinodal decomposition occurs where a hybrid homogeneous phase can no longer remain metastably, becomes unstable and thus proceeds to unmix.…”

Radiation-Induced Defects and Effects in Germanate and Tellurite Glasses

“…This interconnected texture of amorphous phases is produced by the heating and cooling cycle of the pulses. Spinodal decomposition was successfully obtained in tellurite glasses using an excimer laser (248 nm) [ 118 ]. These irradiated glasses could find various vital applications such as membranes and sensors—for example, if one of the phases can be selectively etched.…”

Monitoring Cluster Ions Derived from Aptamer-Modified Gold Nanofilms under Laser Desorption/Ionization for the Detection of Circulating Tumor Cells

“…9 The spinodal line represents the stability limit of a superheated unstable substance in the pressure−temperature phase diagram. 10 The homogeneous nucleation and growth of NPs from a nanofilm becomes spontaneous once the sample overcomes the free energy barrier. 11 After initiation of spinodal hydrodynamic dewetting, perturbations in the superheated thin liquid film grow over time, causing the film to become unstable; nanofilaments and/ or NPs will then be formed once the intermolecular forces reach the same value as the surface tension force.…”

“…It has been demonstrated that pulsed-laser irradiation can induce ultrafast thermal effects that can lead to the dewetting of metallic nanofilms and the formation of porous nanosubstrates, nanofilaments, nanoparticles (NPs), and/or self-organized nanopatterns. , Two possible routes for the transformation of metallic nanofilms into NPs (nanoislands) have been proposed: (i) heterogeneous nucleation from liquid phases located on defects or contaminants and (ii) rupture of the film as a result of hydrodynamic spinodal instability during thin film/spinodal dewetting. , Recently, spinodal dewetting has been demonstrated as having the most significant effect on the transformation of metallic nanofilms when irradiated with a nanosecond-pulsed laser . The spinodal line represents the stability limit of a superheated unstable substance in the pressure–temperature phase diagram . The homogeneous nucleation and growth of NPs from a nanofilm becomes spontaneous once the sample overcomes the free energy barrier .…”

“…The homogeneous nucleation and growth of NPs from a nanofilm becomes spontaneous once the sample overcomes the free energy barrier . After initiation of spinodal hydrodynamic dewetting, perturbations in the superheated thin liquid film grow over time, causing the film to become unstable; nanofilaments and/or NPs will then be formed once the intermolecular forces reach the same value as the surface tension force. , Film–substrate and film–film intermolecular interactions play vital roles during thin film spinodal dewetting. − Evaporation of the metal and the formation of metallic cluster ions in gaseous phase presumably accompany the transformation of the nanofilm, yet most of the previously reported proposed mechanisms of nanofilm dewetting have assumed no losses of metal. − Although analyses of metallic cluster ions can provide insight into the transformation mechanisms of nanofilm, related studies and applications are rare. , …”