Novel Ultrafast Synthesis of Perovskites via Commercial Laser Engraving

Abstract

We present a rapid, energy-efficient, and ecofriendly route for the synthesis of alkaline earth titanate perovskites—CaTiO₃, SrTiO₃, and BaTiO₃—using an affordable, commercially available CO₂ laser engraver, commonly found in makerspaces and small-scale workshops. The method involves direct laser irradiation of compacted pellets composed of low-cost, abundant, and non-toxic precursors: TiO₂ and alkaline earth carbonates (CaCO₃, SrCO₃, BaCO₃). CaTiO₃ and BaTiO₃ were synthesized with phase purities exceeding 97%, eliminating the need for conventional high-temperature furnaces or prolonged thermal treatments. X-ray diffraction (XRD) coupled with Rietveld refinement confirmed the formation of orthorhombic CaTiO₃ (Pbnm), cubic SrTiO₃ (Pm3⁻m), and tetragonal BaTiO₃ (P4mm). Raman spectroscopy independently corroborated the perovskite structures, revealing vibrational fingerprints consistent with the expected crystal symmetries and Ti–O bonding environments. All samples contained only small amounts of unreacted anatase TiO₂, while BaTiO₃ exhibited a partially amorphous fraction, attributed to the sluggish crystallization kinetics of the Ba–Ti system and the rapid quenching inherent to laser processing. Transmission electron microscopy (TEM) revealed nanoparticles with average sizes of 50–150 nm, indicative of localized melting followed by ultrafast solidification. This solvent-free, low-energy, and highly accessible approach, enabled by widely available desktop laser systems, demonstrates exceptional simplicity, scalability, and sustainability. It offers a compelling alternative to conventional ceramic processing, with broad potential for the fabrication of functional oxides in applications ranging from electronics to photocatalysis.

1. Introduction

Perovskites constitute a broad family of inorganic compounds with the general crystal structure ABO₃ [1,2]. In this framework, the A-site is typically occupied by a large cation, such as alkaline earth metals (Ca²⁺, Sr²⁺, Ba²⁺) or certain lanthanides, while the B-site hosts a smaller transition metal ion, commonly Ti⁴⁺, Fe³⁺, or Mn³⁺ [3]. This architecture provides exceptional structural flexibility, allowing extensive ionic substitution without compromising crystal stability [4]. Among perovskites, alkaline earth titanates, where Ti⁴⁺ occupies the B-site and Ca²⁺, Sr²⁺, or Ba²⁺ the A-site, have attracted significant interest due to their distinctive electrochemical, optical, and structural properties [5]. These A-site cations critically influence lattice geometry and modulate key phenomena such as ionic conductivity, electric polarization, and response to external stimuli [6]. For example, calcium titanate (CaTiO₃) is valued for its high thermal and chemical stability, making it suitable for harsh environments [7]. Strontium titanate (SrTiO₃) exhibits semiconducting behavior and can accommodate oxygen vacancies that enhance its electrical conductivity under reducing conditions; it is widely employed as a substrate in advanced electronic devices [8]. Barium titanate (BaTiO₃), in turn, is one of the most studied ferroelectric materials and has long been used in ceramic capacitors and piezoelectric components [9]. Importantly, the functional properties of these titanates can be further engineered through doping or solid-solution formation [10]. Their synthesis can be achieved via various methods, each with specific advantages and limitations. The most common approaches include solid-state reaction [11], sol–gel processing [12], chemical precipitation [13], hydrothermal/solvothermal synthesis [14], and laser ablation [15]. Solid-state synthesis involves mechanical mixing followed by high-temperature calcination of solid precursors; although straightforward, it is energy-intensive. Laser ablation techniques have been extensively studied and applied to produce nanoparticles, thin films, and surface modifications. Conventional pulsed laser ablation uses high-energy pulses to remove or transform surface material, offering high spatial precision and control. However, its implementation is limited by high equipment costs and operational complexity, which have restricted its wider adoption [16]. To the best of our knowledge, this is the first report on perovskite synthesis using a commercially available CO₂ laser engraver. In this work, we propose an innovative approach that leverages an off-the-shelf laser engraver, originally designed for cutting and engraving materials such as wood, acrylic, or textiles for the synthesis of alkaline earth titanate perovskites (CaTiO₃, SrTiO₃, and BaTiO₃). The system employs a continuous-wave 40 W CO₂ laser and costs approximately 1000 USD (2025), making it a highly affordable and accessible alternative to specialized laser systems used in advanced research. Although the underlying physical principle—laser–matter interaction—is conceptually similar to conventional techniques, the use of a low-cost commercial engraver adds significant practical value by enabling implementation in resource-limited laboratories and enhancing scalability for industrial or educational settings.

Table 1. Comparative table of the main methods of perovskite synthesis.

Method	Advantages	Disadvantages	Ref.
Sol–gel	- High homogeneity and purity - Precise stoichiometry control - Low synthesis temperature	- Expensive precursors - Long processing times - Limited scalability	[17]
Solid-state	- Simple and cost-effective - Good reproducibility - Scalable to industrial level	- High synthesis temperature (>1000 °C) - Low homogeneity - Long reaction times	[18]
Hydrothermal/ Solvothermal	- Low synthesis temperature - Control over morphology - Possibility of obtaining metastable phases	- Autoclave equipment - Small-scale production - Longer reaction times	[19]
Chemical Vapor Deposition (CVD)	- Excellent crystalline quality - High purity and morphology control	- High equipment cost - Requires volatile and toxic precursors - Limited scalability	[20]
Pulsed Laser Deposition (PLD)	- Synthesis of complex phases - Does not require calcination - Production of nanoparticles or thin films	- Limited thickness - Formation of an amorphous phase - Reduced scalability - High laser cost	[21]
Laser engraver	- Rapid and efficient - No calcination required - Nanoparticle production - Low energy consumption - Eco-friendly	- Limited to shallow processing depths (~2 mm) - Some perovskites have an amorphous fraction.	This work

provides a comparative summary of the main advantages and disadvantages of each synthesis method in relation to the method proposed here.

The obtained perovskites were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). In addition, structural refinement was performed using the Rietveld method on the XRD patterns to determine the crystalline phase, sample purity, and unit cell parameters.

2. Materials and Methods

For the synthesis, the following reagents were used: titanium dioxide (TiO₂) (Spectrum Chemical Mfg. Corp., 99% purity, New Brunswick, NJ, USA), calcium carbonate (CaCO₃) (Desarrollo de Especialidades Químicas, 99% purity, García, Mexico), strontium carbonate (SrCO₃) (Riedel-de Haën, Seelze, Germany), and barium carbonate (BaCO₃) (Fermont, QC, Canada). The experimental setup consisted of a commercial CO₂ laser engraver, Laser Machine model 3020 (Figure 1). The synthesized perovskites were characterized by X-ray (XRD). Diffraction patterns were acquired on a Panalytical X’Pert PRO diffractometer operating in Bragg–Brentano geometry, using Cu Kα radiation (λ = 1.54108 Å) at 40 kV and 30 mA. Data were collected in the 2θ range of 20–90°, with a step size of 0.017°. Phase composition and average crystallite size were determined from the XRD patterns. Phase identification was performed by matching the experimental patterns against reference entries in the International Centre for Diffraction Data (ICDD) Powder Diffraction File (PDF) 2010 database, using X’Pert HighScore Plus software (version 5.1a). Structural refinements were carried out via the Rietveld method, as implemented in the FullProf Suite (2018 free version) [22]. The two-dimensional visualization of the apparent anisotropic crystallite shape was performed using the GFourier program, version 04.06 [23]. Complementary Raman spectroscopy was conducted to confirm perovskite formation. Measurements were carried out on a Horiba LabRam HR Vis-633 spectrometer (HORIBA, Ltd., Kyoto, Japan) equipped with a He–Ne laser (λ = 632.58 nm), scanning the spectral range from 200 to 900 cm⁻¹. Morphological and compositional characterization was performed using a field-emission scanning electron microscope (Hitachi JEOL JSM-7401F, Tokyo, Japan) operated at 10 kV. For transmission electron microscopy (TEM), nanoparticle suspensions were prepared by dispersing the powder in isopropanol to evaluate particle size, shape, and size distribution. Additional morphological imaging was carried out using a scanning electron microscope (SEM), (Hitachi SU3500, Tokyo, Japan). Optical microscopy was performed using a Dino Lite Edge Plus 900X microscope (Dunwell Tech, Inc. (Dino-Lite Americas), Torrance, CA, USA).

The equipment used was a commercial desktop CO₂ laser engraver, operating at a wavelength of 10.6 µm (mid-infrared), which is ideal for processing non-metallic materials. This type of system has a nominal output power between 30 and 40 W. The laser beam is generated in a glass or metal tube filled with a gaseous mixture of CO₂, N₂, and He, electrically excited to produce lasing action. The beam is directed by a moving head mounted on an X–Y rail system and focused onto the sample through a zinc selenide (ZnSe) lens, which is transparent to infrared radiation. The laser was operated in continuous-wave mode, with an approximate focal spot size of 0.35–0.5 mm. No controlled atmosphere was employed; only the equipment’s integrated fume extractor connected to the laboratory’s ventilation system, was activated. The system is primarily designed for engraving, cutting, or marking materials such as wood, acrylic, leather, paper, textiles, ceramics, and certain inorganic compounds. For the synthesis, titanium dioxide (TiO₂) and alkaline earth carbonates (CaCO₃, SrCO₃, BaCO₃) were used as precursors, mixed in equimolar ratios to yield the corresponding titanates. The powders were manually homogenized for 20 min in an agate mortar and subsequently compacted using a stainless-steel die into pellets of 3 cm in diameter and 0.5 cm in thickness, applying an approximate pressure of 250 kPa. These pellets were placed on the work bed of the laser engraver and irradiated at 20% laser power (equivalent to 8 W) and a scanning speed of 20 mm/s (Figure 2). The entire pellet surface was irradiated for 15 min using a raster scanning pattern. All experiments and characterizations were performed in triplicate to ensure reproducibility of the results.

3. Results

3.1. Optical Microscopy

Optical microscopy revealed noticeable changes in the surface coloration of the samples after laser irradiation, consistent with the formation of perovskite phases. As shown in the photographs, the resulting compounds display characteristic colors depending on their composition: calcium titanate (CaTiO₃) exhibits a light brown hue (Figure 3a), strontium titanate (SrTiO₃) appears even lighter within the same chromatic range (Figure 3b), and barium titanate (BaTiO₃) is distinguished by a pale green tint (Figure 3c). Additionally, the images reveal linear marks produced by the laser beam scanning, forming parallel line patterns with slight variations in color intensity depending on the local material composition. The analyzed samples had an area of 7 cm². Following irradiation, the processed material spontaneously detached from the substrate due to differences in thermal expansion: the thermal expansion coefficients of the resulting perovskites are approximately 10 × 10⁻⁶ K⁻¹ [24], whereas that of TiO₂ is around 8 × 10⁻⁶ K⁻¹ [25]. This mismatch induced delamination, enabling the retrieval of a wafer approximately 2 mm thick.

3.2. Scanning Electron Microscopy (SEM)

Scanning electron microscopy (SEM) analyses enabled higher-resolution observation of the regions previously identified by optical microscopy. Laser irradiation produced incisions on the material surface, forming grooves with spacings ranging from 50 to 150 µm (Figure 4a,c). Spherical particles are clearly visible in the micrographs acquired at 5000× magnification (Figure 4b,d), indicating that the material underwent localized melting during irradiation, leading to the formation of microscopic droplets that rapidly solidified. The micrographs also reveal the presence of cracks, likely caused by thermal stresses induced during rapid cooling (thermal shock). Notably, the BaTiO₃ sample (Figure 4e,f) displays pronounced agglomerations; unlike the other perovskites, no grooves are observed. Instead, the particles form a continuous, interconnected network. Compositional analysis by energy-dispersive X-ray spectroscopy (EDS), included in the Supplementary Materials (Figure S2), confirmed that the experimentally determined atomic percentages closely match the ideal stoichiometry of the target perovskites. Furthermore, elemental mapping of BaTiO₃ is provided in Figure S3. Together, these results demonstrate the successful synthesis of perovskite phases with good chemical purity.

3.3. X-Ray Diffraction (XRD) Analysis

X-ray diffraction (XRD) analyses (Figure 5a) reveal the characteristic diffraction patterns of the synthesized perovskites, indexed to the reference crystallographic cards, listed in

Table 2. Structural refinement data for the synthesized perovskites, including lattice parameters, unit cell volume, phase composition, residual factors (Rp and R_wp_), and goodness-of-fit (χ²).

Samples	Space Group	Lattice Parameters (Å)	Volume (Å3)	Phase %	Rp (%)	Rwp (%)	χ2
CaTiO3 Reference PDF 42-0423	Pbnm No. 62 orthorhombic	a = 5.385 b = 5.445 c = 7.657	224	97.42	8.8	11.7	1.32
TiO2 Reference 01-075-1537	I41/amd No. 141 tetragonal	a = b = 3.790 c = 9.520	136	2.58	-	-	-
SrTiO3 Reference 01-079-0175	Pm3−m No. 221 cubic	a = b = c = 3.903	59	83.2	7.73	10.4	2.48
TiO2 Reference 01-075-1537	I41/amd No. 141 tetragonal	a = b = 3.807 c = 9.644	139	16.8	-	-	-
BaTiO3 Reference 01-081-2202	P4mm No. 99 tetragonal	a = b = 3.999 c = 4.029	64	99.15	6.28	9.8	1.81
TiO2 Reference 01-075-1537	I41/amd No. 141 tetragonal	a = b = 3.78 c = 9.519	136	0.85	-	-	-

, confirming the crystalline nature of the obtained materials. A weak signal around 25° 2θ is observed in all three diffractograms, attributable to residual anatase-phase TiO₂ a common precursor that was not fully consumed during the reaction. Despite this minor trace, the diffraction patterns indicate high phase purity, with no detectable secondary phases or impurities. Notably, the BaTiO₃ diffractogram exhibits a significantly more intense diffuse background compared to those of CaTiO₃ and SrTiO₃, indicative of a partially amorphous fraction. This feature can be attributed to the inherently slower crystallization kinetics of the Ba–Ti system, further hindered by the ultrafast quenching inherent to laser irradiation, which restricts the development of long-range crystalline order. This contrast in crystallinity is rooted in perovskite crystallochemistry. The Goldschmidt tolerance factor for BaTiO₃ (t ≈ 1.06) reflects an oversized Ba²⁺ cation relative to the [TiO₆] octahedral framework [26], which complicates structural relaxation under the non-equilibrium thermal conditions of laser processing. In contrast, SrTiO₃ (t ≈ 1.00) and CaTiO₃ (t ≈ 0.97) possess A site ionic radii better matched to the ideal perovskite geometry [27], enabling more efficient nucleation and crystal growth, even under the rapid, localized heating imposed by laser treatment. Although the tolerance factor itself does not directly govern amorphization (kinetic process) it indirectly influences crystallizability. The pronounced tetragonal distortion required in BaTiO₃ involves cooperative atomic displacements that are kinetically demanding. Under fast processing conditions, this structural complexity delays lattice ordering, rendering BaTiO₃ more prone to partial amorphization than its Sr- or Ca-based counterparts. Thus, the tolerance factor modulates phase purity not thermodynamically, but through its effect on crystallization kinetics under non-equilibrium conditions. The average crystallite size (D) was estimated from the line broadening of the most intense diffraction peak in each pattern using the Debye–Scherrer equation. The calculated crystallite sizes are 47 nm for CaTiO₃, 33 nm for SrTiO₃, and 55 nm for BaTiO₃.

3.4. Rietveld Refinement Study

The Rietveld refinement results presented in Table 2 confirm the successful formation of perovskite phases. The CaTiO₃ sample crystallizes in an orthorhombic structure with space group Pbnm (No. 62) and a phase purity of 97.42%, whereas SrTiO₃ adopts the ideal cubic structure corresponding to space group Pm3⁻m (No. 221) with a calculated purity of 83.2%. BaTiO₃ exhibits a dominant tetragonal phase (P4mm, No. 99) accounting for 99.15% of the sample. No evidence of secondary phases was detected in any case, except for the presence of residual anatase TiO₂, as previously mentioned. Overall, the low χ² values and R refinement factors indicate a good fit between the structural model and the experimental data, confirming the successful synthesis of highly crystalline and phase-pure perovskites. Rietveld refinement patterns are provided in the Supplementary Materials (Figure S1), showing the observed diffraction data (Yobs), the calculated pattern (Ycal), the difference curve (Yobs−Ycal), and the Bragg reflection positions of the identified crystalline phases. It should be noted that SrTiO₃ exhibited a significantly lower purity percentage compared to the other synthesized titanates. Although the exact cause of this low yield has not yet been determined, it may be related to factors such as the higher activation energy required for perovskite phase formation, the limited mobility of the Sr²⁺ cation during ultrafast heating, or the slower diffusion kinetics of Sr²⁺ or incomplete decomposition of SrCO₃. Therefore, it would be advisable to optimize the processing parameters, particularly laser power and scanning speed to promote complete formation of the desired phase and minimize the presence of impurities.

3.5. Transmission Electron Microscopy (TEM)

The aggregation of particles was clearly evident in the scanning electron microscopy (SEM) images (Figure 4), a consequence of the localized heating induced by the laser during synthesis. However, transmission electron microscopy (TEM) analysis revealed that these aggregates are composed of nanoparticles with average sizes ranging from 50 to 150 nm. The apparent crystallite morphology was further analyzed using the GFourier software, which reconstructs the three-dimensional shape of crystallites based on the broadening profiles of diffraction peaks, as illustrated in Figure 6. Variations in crystal morphology reflect differences in nucleation and growth kinetics, influenced by the ionic radius and mobility of the A²⁺ cation within the perovskite lattice. It is important to note that the values derived from diffraction (Scherrer equation) correspond to the size of coherent diffracting domains (single crystallites) whereas the TEM images reveal the physical particle size, which may consist of multiple crystallites fused together. This is a characteristic feature of materials synthesized under rapid heating conditions, where abundant nucleation leads to the formation of nanocrystallites [28].

3.6. Raman Spectroscopy Analysis

Raman spectroscopy of alkaline earth titanates provides valuable insight into their structural and vibrational properties, which are intimately linked to the ionic radius of the A-site cation. The Raman spectrum of CaTiO₃ (Figure 5b) is in good agreement with previously reported results [29], which identified eight Raman bands at 183, 227, 247, 288, 339, 470, 494, and 641 cm⁻¹. The band at 641 cm⁻¹ is assigned to the symmetric stretching vibration of the Ti–O bond, consistent with findings by Balachandran et al. [30]. The bands at 470 and 494 cm⁻¹ are associated with torsional modes of the Ti–O bonds, arising from internal vibrations of the oxygen octahedral cage surrounding the Ti⁴⁺ ion. Finally, the bands in the 183–339 cm⁻¹ range are tentatively assigned to rotational modes of the oxygen cage, which are characteristic of orthorhombically distorted perovskites such as CaTiO₃. In contrast, SrTiO₃ adopts a cubic structure, and due to its high symmetry, first-order Raman scattering is forbidden. Consequently, its spectrum exhibits only second-order activity, appearing as two broad bands in the 200–500 cm⁻¹ and 600–800 cm⁻¹ regions, indicative of a highly ordered crystalline lattice. Nevertheless, an intense peak is observed near 146 cm⁻¹, initially attributed to the T₂g mode associated with tangential distortion of the TiO₆ octahedron; however, it may also arise from residual SrCO₃ impurities [31]. BaTiO₃, on the other hand, crystallizes in a ferroelectric tetragonal structure (P4mm) and displays six Raman-active modes (3A₁ + 3E) in the 100–800 cm⁻¹ range. The high-frequency modes at ~520 and ~720 cm⁻¹ are assigned to asymmetric Ti–O stretching vibrations, which are highly sensitive to the off-center displacement of the Ti⁴⁺ ion responsible for spontaneous polarization [32].

Table 3. Raman spectroscopy data for the synthesized perovskites, including peak positions, vibrational modes, and description.

Raman Mode	Wavenumber (cm−1)	Description
CaTiO3
Ag	183	O–Ti–O bending
Ag	227	O–Ti–O bending
Ag	247	O–Ti–O bending
Ag	288	O–Ti–O bending
Ag	339	O–Ti–O bending
Ag	470	Ti–O3 torsional mode
SrTiO3
T2g	~145–150	Antisymmetric mode of TiO6 the octahedron
-	200–500	Second-order band
-	600–800	Second-order band
BaTiO3
A1(TO2)	~267	Vibration mainly of Ti4+ ions in the cell
A1(TO3)	~306	Characteristic sharp peak; displacement of Ti relative to O
A1(LO)	~520	Optical longitudinal mode associated with Ti displacement
A1(LO)	~720	High wavenumber mode; sensitive to tetragonal distortion

Ag: Totally symmetric mode. T₂g: Triply degenerate mode with antisymmetric symmetry. A₁(TO): Transverse optical mode. A₁(LO): Longitudinal optical mode.

provides a detailed assignment of the Raman signals for each sample. The progression from Ca to Sr correlates with a reduction in lattice distortion, which is reflected in a lower number of Raman modes and a shift in Ti–O stretching vibrations to lower frequencies, consistent with the increased unit cell volume and weakened Ti–O bonding. In contrast, BaTiO₃ exhibits higher-frequency modes due to its tetragonal ferroelectric distortion, which selectively shortens certain Ti–O bonds [33].

4. Proposed Mechanism for the Synthesis of ATiO₃ Perovskites by CO₂ Laser Irradiation

This section describes the formation mechanism of alkaline earth titanates using a commercially available CO₂ laser engraver. The process exploits rapid, localized heating to generate non-equilibrium thermal conditions, and proceeds through the following stages:

• Selective absorption of laser radiation

The CO₂ laser emits at 10.6 µm (mid-infrared), a wavelength strongly absorbed by both TiO₂ (anatase phase) and alkaline earth carbonates (CaCO₃, SrCO₃, BaCO₃) due to their vibrational absorption bands in this spectral range [34]. This efficient absorption allows direct conversion of laser energy into heat at the surface of the compacted pellet [35].

2.

Localized Heating and Carbonate Decomposition

At the focal spot, the laser delivers a high power density (~10 kW/cm²), producing extremely rapid heating rates (on the order of 10³ °C/s) [36]. Depending on the precursor composition and irradiation parameters (laser power, dwell time, scanning speed), peak temperatures range from ~700 °C to over 1300 °C, sufficient to drive the endothermic decomposition of carbonates:

CaCO₃ → CaO + CO₂↑ (~600–700 °C; ΔH = +178 kJ/mol)

SrCO₃ → SrO + CO₂↑ (~900–1000 °C; ΔH = +234 kJ/mol)

BaCO₃ → BaO + CO₂↑ (~1100–1300 °C; ΔH = +269 kJ/mol)

Although bulk TiO₂ has a high melting point (~1843 °C), perovskite formation does not require bulk melting. Instead, the freshly formed alkaline earth oxides (CaO, SrO, BaO) react with TiO₂ under the laser’s transient thermal conditions at temperatures significantly below their individual melting points. This suggests the possible involvement of transient liquid phases, which may facilitate rapid atomic rearrangement. Nonetheless, solid-state diffusion remains the dominant mechanism for perovskite crystallization. Cations (Ca²⁺, Sr²⁺, Ba²⁺, Ti⁴⁺) migrate across particle interfaces when sufficient thermal energy is supplied, enabling reorganization into the perovskite structure. In conventional furnace-based synthesis, CaTiO₃ forms above ~1300–1400 °C [37], SrTiO₃ between ~1200–1600 °C [38], and BaTiO₃ between ~1200–1460 °C [39]. However, these thresholds can be markedly reduced by optimizing parameters such as precursor particle size (to increase surface area and shorten diffusion paths) or by extending reaction time under milder thermal conditions.

In our laser-assisted approach, SEM micrographs reveal spherical particles and smooth, fused morphologies, features indicative of localized melting followed by rapid solidification. These observations indirectly support the formation of transient liquid phases, which appear essential for achieving highly crystalline perovskites under ultrafast processing conditions. Critically, laser–material interaction is confined to the focal spot, and perovskite formation at each irradiated site occurs within fractions of a second, driven by the intense power density and rapid heating. The total irradiation time of 15 min reflects only the duration required to raster-scan the entire pellet surface, ensuring uniform energy delivery and complete reaction across the sample.

3.

Ultrafast Cooling and Final Structure Formation

Upon termination of laser irradiation, the material undergoes extremely rapid cooling (>10³ °C/s), driven by the high thermal conductivity of the surrounding substrate [40]. This laser-induced quenching: “Freezes” the newly formed perovskite phase. The newly formed perovskite phase and suppresses grain growth, may introduce microstrains, point defects, or partial amorphization, particularly in BaTiO₃, whose transformation to the stable tetragonal phase typically requires prolonged high-temperature annealing, a condition precluded by the rapid quenching.

In this study, the grain sizes obtained by X-ray diffraction (30–60 nm) correspond to coherently diffracting domains within crystalline regions, whereas transmission electron microscopy (TEM) observations reveal larger particle sizes (50–150 nm). This difference arises because individual crystallites tend to agglomerate in real space. The discrepancy between the two techniques is consistent with the presence of polycrystalline particles composed of multiple coherent grains [41].

5. Conclusions

An innovative and highly efficient methodology has been developed for the synthesis of calcium titanate (CaTiO₃), strontium titanate (SrTiO₃), and barium titanate (BaTiO₃) perovskites, using a commercial laser engraver as the central processing tool. This approach represents a significant advance over conventional ceramic methods. Structural analysis by XRD and Rietveld refinement confirmed the formation of perovskite phases: CaTiO₃ crystallizes in an orthorhombic structure (Pbnm), SrTiO₃ in the ideal cubic structure (Pm3⁻m), and BaTiO₃ in its tetragonal phase (P4mm), with phase purities of 97%, 83%, and 99%, respectively. Notably, BaTiO₃ exhibited a partially amorphous fraction in XRD, attributed to the slower crystallization kinetics of the Ba–Ti system and the ultrafast quenching following laser irradiation. Microstructural studies by transmission electron microscopy (TEM) revealed nanoparticles with sizes ranging from 50 to 150 nm. This method represents a sustainable, energy-efficient, and scalable alternative to conventional routes that require high temperatures, prolonged reaction times, and greater resource consumption. Its application could be extended to other perovskite systems or multifunctional materials, offering promising opportunities for the production of materials used in electronics, photocatalysis, sensors, and energy storage.