Hydrothermal synthesis of submicrometer alpha-alumina from seeded tetraethylammonium hydroxide-peptized aluminum hydroxide

  1. Home
  2. Research
  3. Publications

abstract

Submicrometer alpha-alumina powder was successfully synthesized from seeded aluminum hydroxide peptized with tetraethylammonium hydroxide (TENOH) and hydrothermally treated at 200degreesC, using alpha-alumina particles as seeds. The powders were characterized by XRD, SEM, DTA-TG, and BET analyses. Results showed that seeding could greatly enhance the transition to alpha-alumina at 200degreesC without formation of other transient alumina phases. alpha-Alumina with some amount of boehmite formed in the seeded samples, whereas boehmite was the exclusive phase formed in the nonseeded sample. The morphology of alpha-alumina embedded in the boehmite matrix for the seeded samples suggests a direct transition from aluminum hydroxide to alpha-alumina without the formation of transient alumina phases. The formation of alpha-alumina in the seeded samples at temperatures as low as 200degreesC could be attributed to a favored nucleation in the TENOH-peptized aluminum hydroxide and to the subsequent hydrothermal treatment that supplies the necessary activation energy for crystal growth. Transition of boehmite to alpha-alumina in the hydrothermally treated samples with low-seed contents was significantly promoted by heat-treating the samples at 500degreesC.

keywords

SOL-GEL; BOEHMITE; TRANSFORMATION; ALPHA-AL2O3; GAMMA; ROUTE

subject category

Materials Science

authors

Yang, J; Mei, S; Ferreira, JMF

our authors

foto José Maria da Fonte Ferreira

José Maria da Fonte Ferreira

Retired Professor

Groups

G5 - Biomimetic, Biological and Living Materials

Share this project:

Related Publications

Publication Details

type
Journal Article
year
2003
journal
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
volume
86
publisher
AMER CERAMIC SOC
issn
0002-7820
issue
12
web of science article identifier
WOS:000187451800009

Journal Metrics (JCR 2019)

Journal Impact Factor
3.502
Journal Impact Factor (5 yrs)
3.475
category normalized journal percentile
91.071

Social Interaction

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".


Privacy and Cookie Policy

Personal data

CICECO-Aveiro Institute of Materials respects your privacy, ensuring confidentiality of personal data you share with the institution through this way, not collecting any personal information about you without your consent, under the terms required by General Data Protection Regulations (RGPD).

The data collected in forms are intended exclusively for processing user requests and will not be used for any other purpose, always safeguarding their confidentiality, under the terms of the protection conferred by the aforementioned regulation.

The collection and processing of data is the responsibility of CICECO and its storage is properly protected, only authorized CICECO employees can access the information within the scope of their functions, always being clear in the respective collection forms the purposes for which they are intended. The remaining issues to be considered in this matter will be handled by the University of Aveiro in accordance with the regime established by the GDPR.

Cookies policy

Cookies are small files with alphanumeric information that are stored on your computer's hard drive by your browser and are intended to improve the user experience and enhance website navigation.

Collection and use of technical information

The cookies used on CICECO are anonymous, and no information about our users that allows their personal identification is stored in them.

The technical information recorded consists of:

  • iP (Internet Protocol) address of the visitor;
  • the type of internet browser used by the website visitor and the respective operating system used;
  • the date and time of the consultation;
  • the pages visited on the site and the documents downloaded
  • The technical information collected is used for statistical purposes only.

Cookies used

Session cookies

These cookies are used to record user preferences, such as the language in which websites are displayed or to maintain authenticated user sessions, and are automatically deleted when the browser is closed.

Persistent cookies

These cookies store information that is needed between sessions. For example, a persistent cookie is set to record that you have been made aware of the cookie policy so that the message regarding this policy is not shown again the next time you visit the website. This cookie remains on the computer until it reaches its expiry date or is deleted by the user.

Data protection

The present privacy policy covers the Information System of the University of Aveiro (SIUA), governed by the General Data Protection Regulations (RGPD) Regulation (EU) No. 2016/679, of April 27th, 2016.

Data Protection Officer

The University of Aveiro has a Data Protection Officer (DPO), who ensures compliance of the processing of personal data with the legislation in force, and is available through the following email address epd@ua.pt.

Close