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Effect of Substrate Temperature on Structural and Photoluminescence Properties of ZnO：SiOx Composites

材料科学与工程（中英文A版） 2011年第6期1卷 828-832页

作者： Roberto Lopez Godofredo Garcia Tomas Diaz Enrique Rosendo Hector Juarez Mauricio Pacio ReinaGaleazzi cids-icuap Benemerita Universidad Autonoma de Puebla Puebla Mexico

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Transformation on CdCO3？CdO Thin Films under Annealing in Air Atmosphere

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材料科学与工程（中英文A版） 2013年第5期3卷 289-298页

作者： Ruth Melendrez Luevano Tania Flores Papaqui Juan Carlos Ramirez Garcia Marcial Zamora Tototzintle Jorge R. Cerna Melissa Chivez Portillo Salvador Rosas Castilla Oscar Portillo Moreno School of Sciences Chemical Autonomous University of Puebla Puebla 72001 M~xico cids-icuap AutonomousUniversity of Puebla 72001 Puebla Mdxico

CdCO3 thin films had grown onto glass by chemical bath deposition (CBD), the temperature of the bath (Td) was at 20 °C. The samples were thermal annealed temperature (TAT) in air atmosphere at normal pressure for 2 h at different temperatures in the range of 300-400 °C, in order to perform the crystalline phase transformation from CdCO3→CdO, Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and optical absorption (OA) measurements were carried out to characterized the films. The proportion of constitutive elements measured by means SEM for CdCO3 as-grown were: Cd = 12.8, C = 20.0, O = 67.2; TAT (CdCO3) = 400 °C: Cd = 49.8, O = 50.2, this results indicates good stoichiometric of samples. Patterns XRD show the layer with CdCO3 which has rhombohedral crystallineas-grown peaks at: 2θ = [23.4, 30.2, 36.4, 40.1, 43.8, 48.0, 49.5, 49.9, 58.2, 61.7, 62.9 and 65.5]. TAT (CdCO3) = 400 °C completely disappeared and only peaks of CdO are identified. All of the peaks in this pattern has pure cubic phase of CdO (2θ= [33.1, 38.2, 55.3, 59.9 and 69.3]). The average grain size (GS) which was calculated from the main XRD peak by CdCO3 reduce of 34.5 nm reaching 20 nm respectively was calculated by employing Scherer"s formula. The optical absorption spectra allowed to calculate the values of forbidden bandgap energy (Eg), and hence, the evolution of Eg in the thermally spectra also showed the complete microstructural transformation from as-grown for samples with higher annealing. The critical point of CdCO3→CdO is proposed to occur at TAT = 400 °C, CdCO3 as-grown: Eg = 3.87 eV, TAT (CdCO3) = 400 °C (CdO): Eg = 2.31 eV.

关键词：氧化镉薄膜退火温度空气气氛扫描电子显微镜光谱计算薄膜生长 X-射线衍射平均晶粒尺寸

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Investigation of Chemical Bath Deposition of ZnO Nanocrystals Thin Films Using Different ZnNO3 Concentration

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材料科学与工程（中英文A版） 2012年第5期2卷 442-453页

作者： Miguel Hemandez Hernandez Martin Lazcano Hernendez Juan Hernandez Tecorralcol Gabriel Juarez Diaz Melissa Chavez Portillo Salvador Rosas Castilla L. Chaltel Lima Oscar Portillo Moreno Facultad de Ciencias Quimicas Benemerita Universidad Autonoma de Puebla Moxico Puebla Mexico cids-icuap Benemerita Universidad A utonoma de Puebla Moxico

In this work, thin films growth at different ZnNO3 concentrations: 0.02 M, 0.03 M and 0.04 M by chemical bath deposition (CBD) as-prepared on glass substrates at 80 °C ± 2 °C. Patterns Diffraction x-ray (DRX) shown peaks 2θ = (31.72, 32.769, 34.36, 36.10, 47.44, 56.52, 62.78, 67.84 and 69.02), at concentration 0.02 M show formation from hydrozincite [Zn5(CO3)2(OH)6]. The optical band gap shifts from 3.8 eV to 3.6 eV. Photoluminescence (PL) spectra show intensity variation of the green emission (GE) may be resulted from variation of the intrinsic defect in ZnO films, such zinc vacancy (VZn), oxygen vacancy (VO), and interstitial zinc (Zni), interstitial oxygen (Oi). The presence of defects in our samples is responsible for the observed broad visible PL bands; this indicates reductions of oxygen vacancies and increase of oxygen interstitials. It could be believed that the presence of defects in samples is responsible for the observed broad visible PL band. The concentration increased the visible defect luminescence, which might be due to improvement to sample stoichiometric. The presence of both green emission (GE) and yellow emission (YE) can be seen through the deconvolution of the defect increasing the concentration, the position of the GE shifted from 1.96-2.45 eV and the increase of its intensity. The shifts of these two visible PL bands might be due to changes in local environments of the defects centers in samples due to increased concentration. Therefore, the GE relate to donor levels dominated due to increase of oxygen vacancies. ZnO is an n-type semiconductor and it means that most defects are Zn interstitials and oxygen vacancies. Raman spectra showed increase of the 437 cm-1 (E2 mode) peak intensity due concentration 0.4 M.

关键词： ZnO薄膜 O3浓度化学浴沉积纳米晶薄膜慢性粒细胞白血病缺陷中心绿色发光强度变化

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Growth of PbS： Ni2＋ Nanocrystals Thin Films by Chemical Bath

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材料科学与工程（中英文A版） 2012年第5期2卷 410-422页

作者： Melissa Chavez Portillo Javier Martinez Juarez Gustavo Abarca Avila Marcial Zamora Tototzintle MacarioMartinez Barragan Jorge. R. Cema Martin Lazcano Hernandez Salvador Rosas Castilla Brenda CrespoSnchez Andrea Celeste Palacios Lopez and Oscar Portillo Moreno cids-icuap Benemerita Universidad Autonoma de Puebla (BUAP) Mexico Facultad de Ciencias Quimicas Benemdrita Universidad Autonoma de Puebla (BUAP) Moxico.C. U. Puebla Moxico

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<i>Ab Initio</i>Molecular Orbital Calculation for Optical and Electronic Properties Evaluation of Small and Medium Size Silicon Nano-Clusters Found in Silicon Rich Oxide Films

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Journal of Modern Physics 2013年第11期4卷 1-26页

作者： Néstor David Espinosa Torres José Francisco Javier Flores Gracia José Alberto Luna López Juan Carlos Ramírez García Alfredo Morales Sánchez José Luis Sosa Sánchez David Hernández de la Luz Francisco Morales Morales Research Center for Advanced Materials S.C. Unit Monterrey-PIIT Apodaca México Research Center for Semiconductor Devices CIDS-ICUAP-BUAP Puebla México The Faculty of Chemical Sciences BUAP Puebla México

In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic properties are often dependent on the size of the systems and the way in which the atoms in these clusters are bonded. Generally, these nano-structures display optical and electronic properties significantly different of those found in corresponding bulk materials. Silicon agglomerates found in Silicon Rich Oxide (SRO) films have optical properties, which have reported as depended directly on nano-crystal size. Furthermore, the room temperature photoluminescence (PL) of Silicon Rich Oxides (SRO) has repeatedly generated a huge interest due to their possible applications in optoelectronic devices. However, a plausible emission mechanism has not yet widespread acceptance of the scientific community. In this research, we employed the Density Functional Theory with a functional B3LYP and a basis set 6 - 31G* to calculate the optical and electronic properties of small (six to ten silicon atoms) and medium size clusters of silicon (constituted of eleven to fourteen silicon atoms). With the theoretical calculation of the structural and optical properties of silicon clusters, it is possible to evaluate the contribution of silicon agglomerates in the luminescent emission mechanism experimentally found in thin SRO films.

关键词： Nano-Crystals Silicon Clusters Silicon-Rich Oxide Luminescence Magic-Number

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Properties of Chemical Bath Deposited PbS Thin Films Doped with Cd2＋

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材料科学与工程（中英文A版） 2011年第6期1卷 759-767页

作者： Oscar Portillo Moreno Melissa Chavez Portillo Miriam Moreno Flores Javier Martinez Juarez Gustavo Abarca Avila Rosendo Lozada Morales Orlando Zelaya Angel Facultad de Ciencias Quimicas BUAP C. U. Puebla Mexico cids-icuap C. U. Puebla Mexico Facultad de Ciencias Fisicomatematicas BUAP C. U. Puebla Mexico Departamento de Fisiea Centro de Investigacion y de Estudios Avanzados Av. IPN 2508 Col San Pedro Zacatenco Mexico

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Optical and Structural Properties CdSe： Ni^2＋ Nanocrystals

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材料科学与工程（中英文A版） 2014年第9期4卷 309-314页

作者： Marcial Zamora Tototzintle Martin Lazcano Hemandez Arturo Sosa Sanchez Leslie Chaltel Lima Estephani Balderrabano Perdomo MoisesAraiza Garcia Miguel Hernadez Hemandez Rey Baltazar Lopez Oscar Portillo Moreno Laboratory Materials Science Faculty of Chemical Sciences Autonomous University of Puebla Puebla 72001 Pue Mexico cids-icuap C. U Puebla M~xico.AutonomousUniversity of Puebla Puebla 72001 Pue Mexico ITSM Campus Puebla Via Atlixcayolt 2301 Col. Reserva Territorial. Atlixcayolt Puebla 72001 Pue Mexico Faculty of Electronic Sciences Autonomous University of Puebla Puebla 72001 Pue Mexico

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Characterization of Chemical Bath Deposited CdS, CdSe and PbS

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材料科学与工程（中英文A版） 2011年第5X期1卷 692-704页

作者： Oscar Portillo Moreno Gustavo Abarca Avila Jorge R. Cerna Juan Hernandez Tecorralco Melissa Chavez Portillo Javier Martinez Juarez Rosendo Lozada Morales Orlando Zelaya Angel Facultad de Ciencias Quimicas Benemerita Universidad Autonoma de Puebla Mexico Col. Sn. Manuel Puebla Pue. Mexico cids-icuap Benemerita Universidad Autonoma de Puebla Mexico. Col. Sn. Manuel Puebla Pue. Mexico Fac. Ciencias Fisicomatematicas Postgrado en Optoelectronica Benemerita Universidad Autonoma de Puebla Mexico Col. Sn Manuel Puebla Pue. Mexico Departamento de Fisica Centro de Investigacion y de Estudios de Estudios Avanzados del IPN 07360 Mexico D. F. Mexico

CdS, CdSe and PbS films were grown onto glass by chemical bath deposition (CBD). Different constant deposition temperatures (Td) were employed in the range 0-80 °C with subintervals of 10 °C. Concentration of reagents, pH, and stirring were maintained constants. A microcrystalline mixture CdCO3 and CdS were grown. At intermediates Td values a mixture of both materials present. i. e., For Td? 40 °C, the intensity of the main of X-ray Diffraction (XRD) CdS peak is abruptly reduced. By scanning electronic microscopy (SEM) with Td = 80 °C, concentration atomic: Cd = 49.10, S = 51.90, for Td? 70 °C, increase of carbon and oxygen. The CdSe, average grain size (GS) increased monotonic with Td, reaching saturation of 70 °C, with GS values of 5-16 nm. At low Td values (0-20 °C), the structural phase was found, and the high Td = 70 °C on material 5-16 nm was appreciated transition to phase: Wurzite (W)? Zinbclende (ZB) and phases mixture: W/ZB, grain size (GS) 9-27 nm. By (XRD), PbS grow in W phase at all films, for Td = 60 °C, was observed preferential orientation in plane [111] with (GS) of 19-26 nm also a Gibbs free energy calculation is included.

关键词： CdSe 化学浴沉积 PBS 平均晶粒尺寸扫描电子显微镜表征吉布斯自由能薄膜生长

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Sensory denervation with capsaicin reduces ovarian follicular development and delays the onset of puberty in guinea pigs

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Advances in Reproductive Sciences 2013年第3期1卷 29-37页

作者： Victorino Alatriste Irma Herrera-Camacho María I. Martínez Ilhicamina D. Limón Oscar González-Flores Félix Luna Centro de Investigación en Reproducción Animal UAT-CINVESTAV Tlaxcala México Centro de Química ICUAP Puebla México Departamento de Farmacia FCQ-BUAP Puebla México

Introduction: It has been documented that mammalian ovaries receive sympathetic, parasympathetic and sensory nerve fibers. The aim of this work was to investigate the effects of sensory denervation with capsaicin at the first vaginal opening (FVO) on follicular development and the expression of TRPV1 receptors in ovary cells as well as in the dorsal root ganglia (DRGs) and lumbar dorsal spinal cord neurons of guinea pigs. The DRGs and lumbar dorsal spinal cord neurons serve as a nerve connection from the ovaries to the CNS. Materials and Methods: Female guinea pigs received a subcutaneous injection of capsaicin (30 mM) at 10 days of age (P10), while control animals were injected with vehicle. Using light microscopy, we counted healthy preantral follicles (HPF), healthy antral follicles (HAF), atretic preantral follicles (APF), and atretic antral follicles (AAF) in the ovaries at the FVO, and the numbers of TRPV1-positive cells were counted in the ovarian follicles, DRGs, and lumbar dorsal spinal cord (L2-L4) neurons by immunohistochemistry. Results: Guinea pigs treated with capsaicin showed a significant delay of FVO in comparison with the control animals (36 vs. 44 days). In the ovaries, the number of preantral and antral follicles decreased significantly. Additionally, the number of TRPV1-positive thecainterstitial cells of the antral follicles was reduced significantly, and the number of TRPV1-positive neurons in the DRGs and lumbar dorsal spinal cord (L2-L4) decreased. Thus, we showed that TRPV1 receptors throughout the sensory fibers modulate ovarian follicular development and the onset of puberty in guinea pigs. Conclusion: Sensory denervation decreases ovarian follicular development and delays the onset of puberty of guinea pigs. Our data support the idea that through TRPV1 receptors, ovarian afferent fibers sense local stimuli that are sent to the CNS.

关键词： TRPV1 Receptors Capsaicin DRG Spinal Cord Ovary Guinea Pigs

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Forecast of the Luminescent Phenomena of Silicon Rich Oxide Films off Stoichiometry by Means of the Global Reaction Model

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Journal of Modern Physics 2015年第11期6卷 1679-1694页

作者： Néstor David Espinosa-Torres José álvaro David Hernández de la Luz José Francisco Javier Flores-Gracia José Alberto Luna-López Javier Martínez-Juárez Gregorio Flores-Carrasco IC-cids Benemérita Universidad Autónoma de Puebla Puebla México Ex Graduate Research Trainee at Plasma Processing Laboratory Chemical Engineering Department McGill University Montreal Canada Department of Materials Science and Engineering and Chemical Engineering University Carlos III of Madrid and IAAB Madrid Spain

The Global Reaction Model describes a set of chemical reactions that can potentially occur during the process of obtaining silicon rich oxide (SRO) films, regardless of the technique used to grow such films which are an outside stoichiometry material. Particularly, chemical reactions that occur during the process of growing of SRO films by LPCVD technique are highlighted in this model. We suggest and evaluate either some types of molecules or resulting nanostructures and we predict theoretically, by applying the density functional theory, the contribution that they may have to the phenomenon of luminescence which is measured in SRO films. Also, we have calculated the opto-electronic properties of SRO films. The suggested model provides enough information required to identify the molecular structures resulting from the presence of defects in SRO films and also those corresponding to charged structures. It is also possible to detect the molecular structures which are modified due to the effect of heat treatment, and identify the presence of different oxidation states inclusive the formation of siloxanes.

关键词： Global Reactions Model Silicon Rich-Oxide Defects LPCVD Luminescence

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