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Design and tailoring of one-dimensional ZnO nanomaterials for photocatalytic degradation of organic dyes: a review

Authors:
Morasae Samadi at Alzahra University
Morasae Samadi
Mohammad Zirak at Hakim Sabzevari University
Mohammad Zirak
Amene Naseri at Agricultural Biotechnology Research Institute of Iran
Amene Naseri
Malihe Kheirabadi at Sharif University of Technology
Malihe Kheirabadi
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Abstract and Figures

Photocatalysis using semiconductors has emerged as a promising wastewater treatment process to overcome the major challenges faced by conventional technologies. The advantages of ZnO nanomaterials over other semiconductors, and their structure-dependent properties, make them important building blocks in nanotechnology as multifunctional materials. Moreover, it has been confirmed that ZnO nanomaterials can exhibit high performance in photodegradation of organic dyes for treatment of industrial effluent. The wurtzite structure of ZnO contains polar and nonpolar planes; the low surface energy and thermodynamic stability of the nonpolar planes enable formation of one-dimensional (1D) ZnO structures, which are desirable compared with zero-dimensional (0D) and two-dimensional (2D) nanoarchitectures. Also, relative to other forms, the superiority of 1D ZnO nanostructures in dye photodegradation makes them promising as a future research direction and for commercial use. Therefore, understanding the design and synthesis of 1D ZnO nanomaterials is of critical importance for the development of novel and high-performance photocatalysts. Rational design of 1D ZnO nanophotocatalysts is thus required to enhance their photodegradation activity via efficient separation of charge carriers, increased surface-to-volume ratio, enhanced light absorption capacity, and improved stability/reusability. We briefly describe herein the most widely applied synthesis methods, including vapor-phase and solution-based strategies, to understand different methods for tailoring 1D ZnO nanophotocatalysts. Moreover, to elucidate the effect of their physical/chemical properties on the photodegradation efficiency, all the modification methods are categorized into four different approaches, viz. (1) morphology control, (2) induction of defects, (3) modulation by doping, and (4) formation of hybrids and heterojunctions. An overview of all aspects of charge generation, separation, and transfer during dye photodegradation by engineered 1D ZnO nanomaterials is also provided. Graphical abstract Open image in new window
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Vol.:(0123456789)
Research on Chemical Intermediates (2019) 45:2197–2254
https://doi.org/10.1007/s11164-018-03729-5
1 3
Design andtailoring ofone‑dimensional ZnO
nanomaterials forphotocatalytic degradation oforganic
dyes: areview
MorasaeSamadi1· MohammadZirak2· AmeneNaseri3· MaliheKheirabadi1·
MahdiEbrahimi1· AlirezaZ.Moshfegh1,3
Received: 27 July 2018 / Accepted: 26 December 2018 / Published online: 25 January 2019
© Springer Nature B.V. 2019
Abstract
Photocatalysis using semiconductors has emerged as a promising wastewater treat-
ment process to overcome the major challenges faced by conventional technologies.
The advantages of ZnO nanomaterials over other semiconductors, and their struc-
ture-dependent properties, make them important building blocks in nanotechnology
as multifunctional materials. Moreover, it has been confirmed that ZnO nanoma-
terials can exhibit high performance in photodegradation of organic dyes for treat-
ment of industrial effluent. The wurtzite structure of ZnO contains polar and non-
polar planes; the low surface energy and thermodynamic stability of the nonpolar
planes enable formation of one-dimensional (1D) ZnO structures, which are desir-
able compared with zero-dimensional (0D) and two-dimensional (2D) nanoarchitec-
tures. Also, relative to other forms, the superiority of 1D ZnO nanostructures in dye
photodegradation makes them promising as a future research direction and for com-
mercial use. Therefore, understanding the design and synthesis of 1D ZnO nanoma-
terials is of critical importance for the development of novel and high-performance
photocatalysts. Rational design of 1D ZnO nanophotocatalysts is thus required to
enhance their photodegradation activity via efficient separation of charge carriers,
increased surface-to-volume ratio, enhanced light absorption capacity, and improved
stability/reusability. We briefly describe herein the most widely applied synthesis
methods, including vapor-phase and solution-based strategies, to understand differ-
ent methods for tailoring 1D ZnO nanophotocatalysts. Moreover, to elucidate the
effect of their physical/chemical properties on the photodegradation efficiency, all
the modification methods are categorized into four different approaches, viz. (1)
* Alireza Z. Moshfegh
moshfegh@sharif.edu
1 Department ofPhysics, Sharif University ofTechnology, P.O. Box11155-9161, Tehran, Iran
2 Department ofPhysics, Hakim Sabzevari University, P. O. Box961797648, Sabzevar, Iran
3 Institute forNanoscience andNanotechnology, Sharif University ofTechnology,
P.O. Box14588-89694, Tehran, Iran
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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