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NanoMat 2018
Nano Research & Applications
ISSN: 2471-9838
Page 83
April 26-27, 2018
Rome, Italy
17
th
Edition of International Conference on
Emerging Trends in
Materials Science and
Nanotechnology
N
owadays, sunscreens are formulated by using TiO
2
and ZnO
nanoparticles because they are efficient inorganic UV filters.
In fact micro sized TiO
2
and ZnO have been increasingly replaced
by TiO
2
and ZnO nanoparticles in order to solve the cosmetic
drawback of the white opaque sunscreens apart from the higher
yield that nanoparticles suppose. Also the aggregation state of
the particles in sunscreens is related to the solar protection factor
(SPF) of the final emulsion. In this sense, dispersed nanoparticles
into sunscreens increase the SPF value, but it means a possible
leading to their incorporation into the stratum cornea, the outer
layer of the skin. Moreover, when TiO
2
is irradiated produces free
radicals which are implicated in a number of potential health
issues such as skin aging because of the formation of reactive
oxygen species (ROS). In this work, composites combining TiO
2
micro particles and ZnO nanoparticles have been achieved by
using several synthesis and dispersion methods. It has been
demonstratedby the incorporationof thedifferent composites into
sunscreens that the presence of nanoparticles anchored over TiO
2
micro particles allows increasing the efficiency of nanoparticles
but decreases the possible health problems by their absorption
as nanoparticles. The aim of these new composites is to gain the
advantages of inorganic nanoparticles avoiding their potential
drawbacks. Hence, the combination of both oxides provokes
higher SPF value and lower photodegradation, in comparison with
TiO
2
micro particles. Moreover, the disposition of ZnO and TiO
2
particles means a positive synergy by the recombination of photo
induced electrons holes, which decreases the formation of free
radicals.
jjreinosa@icv.csic.esEffectiveness in UV absorption of hierarchical nano ZnO-
microTiO
2
composites with photodegradation inhibition
J J Reinosa
Institute of Ceramics and Glass, Spain
Nano Res Appl, Volume:4
DOI: 10.21767/2471-9838-C1-009