Structure, microstructure and surface of Nd 3+ -doped mesoporous anatase-phase TiO 2

  • PDF / 1,612,003 Bytes
  • 7 Pages / 595.276 x 790.866 pts Page_size
  • 73 Downloads / 189 Views

DOWNLOAD

REPORT


Structure, microstructure and surface of ­Nd3+‑doped mesoporous anatase‑phase ­TiO2 Balter Trujillo‑Navarrete1   · Francisco Paraguay‑Delgado2   · Sergio Pérez‑Sicairos1  Received: 17 February 2020 / Accepted: 28 June 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020

Abstract We prepared nanocrystalline mesoporous anatase-phase ­TiO2 doped in the range from 0.0 to 1.0 at.% of ­Nd3+ by the reverse microemulsion method (RMM). The analysis of electron microscopy of the nanocrystal revealed a truncated-tetragonal bipyramidal shape and agglomerates of spheroidal nanoparticles with inter-particle porosity. The inductively coupled plasma (ICP) technique corroborated the doping concentrations. The analysis of structural parameters by the Rietveld refinement ­ d3+ insertion in the lattice. The microtechnique indicated the variation of Ti–O(1) and Ti–O(2) bond lengths, suggesting the N structural analysis by the Williamson–Hall plot (WH) and whole powder pattern fitting (WPPF) revealed that the doping addition has a slight inhibition effect on the crystal size (6–8 nm) with a minor strain increment. The surface analysis from ­N2 adsorption/desorption isotherms showed that the incorporation of the dopant in low amounts improved the mesoporous structure stability, increased the diameter of opening pores, and changed the pore structure network. The XPS analysis of the chemical states on the surface suggests that the ­Nd3+ presence changed the Ti 2p region and the presence of the two chemical states of oxygen ­(OI and ­OII). Keywords  Neodymium · Rare earth oxide · Mesoporous catalyst · TiO2 · Microstructure analysis · Surface area measurement

1 Introduction In the last decade, there has been an increasing interest in mesoporous metal oxides due to their properties such as high surface area, pore structure, and active sites. An ideal candidate to synthesize ordered or non-ordered mesoporous materials is titanium dioxide (anatase phase). This is because it is easy to produce at low-cost and only slightly harmful to the environment, and has known optoelectronic properties [1]. Synthesis strategies have been proposed to obtain the mesoporous material as the use of a template to get ordered Electronic supplementary material  The online version of this article (https​://doi.org/10.1007/s0033​9-020-03768​-z) contains supplementary material, which is available to authorized users. * Balter Trujillo‑Navarrete [email protected] 1



Tecnológico Nacional de México/Instituto Tecnológico de Tijuana/Posgrado en Ciencia de la Ingeniería, Tijuana, BC, México



Advanced Materials Research Center SC, Chihuahua, CHIH, México

2

pores via Gemini surfactant, cationic, neutral organic surfactant (e.g., amphiphilic block copolymers) or ball polystyrene [2, 3], or disordered pores (template-free) resulting from intra-particle or inter-particle porosity [4–7]. In recent times, the nanocrystalline mesoporous anatasephase TiO2 system (mesoporous-TiO2) has been doped using rare earth elements (REE) to enhance its prop