A comparative study of the photocatalytic oxidation of propane on anatase, rutile, and mixed-phase anatase–rutile TiO2 nanoparticles: Role of surface intermediates

The evolution of desirable physico-chemical properties in high performance photocatalyst materials involves steps that must be carefully designed, controlled, and optimized. This study investigated the role of key parameter in the preparation and photocatalytic activity analysis of the mixed phase of anatase/rutile TiO2 nanoparticles, prepared via sol-gel method containing titanium-n-butoxide Ti(OBu)4 as a precursor material, nitric acid as catalyst, and isopropanol as solvent. The prepared TiO2 nanoparticles were characterized by means of XRD, SEM, and BET analyses, and UV-Vis-NIR spectroscopy. The results indicated that the calcination temperature play an important role in the physico-chemical properties and photocatalytic activity of the resulting TiO2 nanoparticles. Different calcination temperatures would result in different composition of anatase and rutile. The photocatalytic activity of the prepared mixed phase of anatase/rutile TiO2 nanoparticles was measured by photodegradation of 50 ppm phenol in an aqueous solution. The commercial anatase from Sigma-Aldrich and Degussa P25 were used for comparison purpose. The mixed phase of anatase/rutile TiO2 nanoparticles (consists of 38.3% anatase and 61.7% rutile) that was prepared at 400°C exhibited the highest photocatalytic activity of 84.88% degradation of phenol. The result was comparable with photocatalytic activity demonstrated by Degussa P25 by 1.54% difference in phenol degradation. The results also suggested that the mixed phase of anatase/rutile TiO2 nanoparticles is a promising candidate for the phenol degradation process. The high performance of photocatalyst materials may be obtained by adopting a judicious combination of anatase/rutile and optimized calcination conditions.

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The role of rutile TiO2 nanoparticles on weathering resistance of photocurable acrylate urethane coating

Vietnam Journal of Chemistry ◽

10.1002/vjch.2019000129 ◽

2020 ◽

Vol 58 (3) ◽

pp. 314-320

Author(s):

Nguyen Thien Vuong

Keyword(s):

Tio2 Nanoparticles ◽

Rutile Tio2 ◽

Weathering Resistance

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Facile Formation of Anatase/Rutile TiO2 Nanocomposites with Enhanced Photocatalytic Activity

Molecules ◽

10.3390/molecules24162996 ◽

2019 ◽

Vol 24 (16) ◽

pp. 2996 ◽

Cited By ~ 10

Author(s):

Jing He ◽

Yi-en Du ◽

Yang Bai ◽

Jing An ◽

Xuemei Cai ◽

...

Keyword(s):

Photocatalytic Activity ◽

Tio2 Nanoparticles ◽

Crystal Surface ◽

Sol Gel ◽

Average Particle Size ◽

Mixed Phase ◽

Average Particle ◽

Light Illumination ◽

Potential Candidate ◽

Rutile Tio2

Anatase/rutile mixed-phase TiO2 nanoparticles were synthesized through a simple sol-gel route with further calcination using inexpensive titanium tetrachloride as a titanium source, which effectively reduces the production cost. The structural and optical properties of the prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis adsorption. The specific surface area was also analyzed by Brunauer–Emmett–Teller (BET) method. The anatase/rutile mixed-phase TiO2 nanocomposites containing of rod-like, cuboid, and some irregularly shaped anatase nanoparticles (exposed {101} facets) with sizes ranging from tens to more than 100 nanometers, and rod-like rutile nanoparticles (exposed {110} facets) with sizes ranging from tens to more than 100 nanometers. The photocatalytic activities of the obtained anatase/rutile mixed-phase TiO2 nanoparticles were investigated and compared by evaluating the degradation of hazardous dye methylene blue (MB) under ultraviolet light illumination. Compared to the commercial Degussa P25-TiO2, the mixed-phase TiO2 nanocomposites show better photocatalytic activity, which can be attributed to the optimal anatase to rutile ratio and the specific exposed crystal surface on the surface. The anatase/rutile TiO2 nanocomposites obtained at pH 1.0 (pH1.0-TiO2) show the best photocatalytic activity, which can be attributed to the optimal heterojunction structure, the smaller average particle size, and the presence of a specific exposed crystal surface. The enhanced photocatalytic activity makes the prepared anatase/rutile TiO2 photocatalysts a potential candidate in the removal of the organic dyes from colored wastewater.

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223 How can the role of N terminal pro B natriuretic peptide (NT-proBNP) be optimised in heart failure screening? A prospective observational comparative study

European Journal of Heart Failure Supplements ◽

10.1016/s1567-4215(04)90150-6 ◽

2004 ◽

Vol 3 (1) ◽

pp. 51 ◽

Cited By ~ 3

Author(s):

M ALBARJAS

Keyword(s):

Heart Failure ◽

Comparative Study ◽

Natriuretic Peptide

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Provision of Remedies for Violation of Economic, Social and Cultural Rights: A Comparative Study of the United Nations, Inter-American and African Human Rights Systems

African Journal of International and Comparative Law ◽

10.3366/ajicl.2020.0314 ◽

2020 ◽

Vol 28 (2) ◽

pp. 298-318

Author(s):

Roman Girma Teshome

Keyword(s):

Human Rights ◽

United Nations ◽

Comparative Study ◽

Economic Rights ◽

Regional Monitoring ◽

Cultural Rights ◽

The Past ◽

The United Nations ◽

To Receive

The effectiveness of human rights adjudicative procedures partly, if not most importantly, hinges upon the adequacy of the remedies they grant and the implementation of those remedies. This assertion also holds water with regard to the international and regional monitoring bodies established to receive individual complaints related to economic, social and cultural rights (hereinafter ‘ESC rights’ or ‘socio-economic rights’). Remedies can serve two major functions: they are meant, first, to rectify the pecuniary and non-pecuniary damage sustained by the particular victim, and second, to resolve systematic problems existing in the state machinery in order to ensure the non-repetition of the act. Hence, the role of remedies is not confined to correcting the past but also shaping the future by providing reforming measures a state has to undertake. The adequacy of remedies awarded by international and regional human rights bodies is also assessed based on these two benchmarks. The present article examines these issues in relation to individual complaint procedures that deal with the violation of ESC rights, with particular reference to the case laws of the three jurisdictions selected for this work, i.e. the United Nations, Inter-American and African Human Rights Systems.

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cAbdullah Yūsuf cAlī & Muhammad Asad: Two Approaches to the English Translation of the Qur'an

Journal of Qur anic Studies ◽

10.3366/jqs.2000.2.1.107 ◽

2000 ◽

Vol 2 (1) ◽

pp. 107-123 ◽

Cited By ~ 1

Author(s):

Muzaffar Iqbal

Keyword(s):

Twentieth Century ◽

Comparative Study ◽

Life Experiences ◽

Academic Career ◽

British India ◽

Human Understanding ◽

English Translations ◽

Political Milieu ◽

The Times

This article attempts to present a comparative study of the role of two twentieth-century English translations of the Qur'an: cAbdullah Yūsuf cAlī's The Meaning of the Glorious Qur'ān and Muḥammad Asad's The Message of the Qur'ān. No two men could have been more different in their background, social and political milieu and life experiences than Yūsuf cAlī and Asad. Yūsuf 'Alī was born and raised in British India and had a brilliant but traditional middle-class academic career. Asad traversed a vast cultural and geographical terrain: from a highly-disciplined childhood in Europe to the deserts of Arabia. Both men lived ‘intensely’ and with deep spiritual yearning. At some time in each of their lives they decided to embark upon the translation of the Qur'an. Their efforts have provided us with two incredibly rich monumental works, which both reflect their own unique approaches and the effects of the times and circumstances in which they lived. A comparative study of these two translations can provide rich insights into the exegesis and the phenomenon of human understanding of the divine text.

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