Antonio Ramirez

Dr. Antonio Ramirez

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Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 August 2023 in Materials Chemistry and Physics
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OKOnyekachi Kalu
Onyekachi Kalu
AAA. Nathan Abutu
A. Nathan Abutu
HPHilda Esparza Ponce
Hilda Esparza Ponce
ARAntonio Ramirez
Antonio Ramirez
RKR.E. Kroon
R.E. Kroon
ARA. Reyes-Rojas
A. Reyes-Rojas

21 May 2025 in Materials
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AHAnel Rocío Carrasco Hernández
Anel Rocío Carrasco Hernández
ARArmando Reyes Reyes-Rojas
Armando Reyes Reyes-Rojas
GGGabriel Rojas George
Gabriel Rojas George
ARAntonio Ramirez
Antonio Ramirez
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
BiFeO3 is a fascinating material with a rhombohedral crystal structure (R3c) at room temperature. This unique structure makes it suitable for use in solar cells, as the interaction of light with the polarized octahedral enhances electron movement. Evaluating its properties on different substrates helps to identify the specific characteristics of thin films. The thin films presented in this work were deposited using reactive RF cathodic sputtering with a homemade 1-inch diameter ceramic target. Their morphology, phase composition, optical, piezoelectric, and ferroelectric properties were evaluated. Fluorine Tin Oxide (FTO) and Indium Tin Oxide (ITO) substrates were used for the presented thin films. The thin films deposited on FTO displayed the “butterfly” behavior typically associated with ferroelectric materials. A d33 value of 2.71 nm/V was determined using SSPFM-DART mode. In contrast, the thin films deposited on ITO at 550 °C reached a maximum saturation polarization of 40.89 μC/cm2 and a remnant polarization of 44.87 μC/cm2, which are the highest values recorded, but did not present the typical “butterfly” behavior. As the grain size increased, the influence of charge defects became more pronounced, leading to an increase in the leakage current. Furthermore, the presence of secondary phases also contributed to this behavior.

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MRMaría Luisa Camacho Ríos
María Luisa Camacho Ríos
Guillermo Herrera-PerezGuillermo Herrera-Perez
Guillermo Herrera-Perez
LRluis carlos rodriguez
luis carlos rodriguez
Mariana Lizbeth Luján AguilarMariana Lizbeth Luján Aguilar
Mariana Lizbeth Luján Aguilar
ARAntonio Ramirez
Antonio Ramirez
JBJosé Antonio Betancourt
José Antonio Betancourt
The current work presents the influence of the magnesiothermic synthesis method on titanium carbide (TiC). In this method, powdered titanium precursors and two carbon sources—turbostratic carbon and carbon nanotubes—were employed in proportions of 10 wt.% and 20 wt.%. The refinement of the X-ray diffraction (XRD) patterns using the Rietveld method for TiC suggests suggested coexistence of two phases, cubic with Fm-3m space group and hexagonal with P3121 space group. In particular, for the sample with 20 wt.% of carbon sources, the XRD refinement revealed that the cubic phase accounted for 94% of the composition, in contrast to a secondary hexagonal phase, Ti6C3.75, which comprised 6%. The influence of carbon on the morphology (particle size and shape) and crystallite size was monitored through bright-field transmission electron microscopy (BF-TEM) imaging and XRD. In samples containing 20 wt.% carbon, a homogeneous morphology in both size (around 11 microns) and shape was observed, along with a reduction in crystallite size (from 22.7 to 17.8 nm). Raman band analysis further revealed vibrational modes indicating that carbon induced disorder in the TiC structure. The magnesiothermic synthesis method developed in this work offers a low-cost approach of interest in the aerospace and automotive industries. Additionally, the study provides significant insights for particles used as additives or reinforcing agents to enhance the mechanical properties of metal matrix composites (MMCs).

16 January 2026 in Processes
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PPPedro Piza
Pedro Piza
GMGriselda Mendoza-Gómez
Griselda Mendoza-Gómez
MRMaría Luisa Camacho Ríos
María Luisa Camacho Ríos
Guillermo Herrera-PerezGuillermo Herrera-Perez
Guillermo Herrera-Perez
LRluis carlos rodriguez
luis carlos rodriguez
Caleb CarreñoCaleb Carreño
Caleb Carreño
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.