4th EucheMs chemistry congress

Poster Session 2
s1222
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - Nanochemistry, Nanotechnology
P - 0 7 1 9
SPrAy-iLGAr ® dePoSition of ControLLABLe
znS nAnodotS And APPLiCAtion for hiGhLy
effiCient thin fiLM SoLAr CeLLS
y. fu 1 , t. KoehLer 1 , M. KrueGer 1 , r. SAez ArAoz 1 ,
M. Ch. Lux-Steiner 1 , d. ABou-rAS 1 , C. h. fiSCher 1
1 Helmholtz-Zentrum Berlin, Institute for Heterogeneous
Materials Systems, Berlin, Germany
The spray ion layer gas reaction (Spray-ILGAR) technique
produces homogeneous, compact metal chalcogenide films used
as buffer layers for thin film solar cells with high efficiencies. It
was a great challenge to elaborate this method for the deposition
of nanodots. Now we show that high quality ZnS nanodots can
be synthesized at low temperature by this sequential, cyclic and
low cost method, which can be scaled up for industrial in-line
production.
The choice of the process parameters allows the control of
particle density and size. The unique sequential process results in
the formation of the nanodot film with good properties. The dots
are rather homogeneous in size, shape and composition, and tend
to keep maximum distance from each other. In contrast, ZnS
nanodots deposited by a continuous spray chemical vapor
deposition (Spray-CVD) are larger and irregular in shape with
inclusions of ZnO. By interpretation of the SEM, TEM, XPS and
mass spectrometry results, the decomposition mechanism of Zn
precursor and the self-limiting growth of ZnS nanodots are
studied.
In addition, a passivation layer/point contact buffer
composed of the ZnS nanodots covered by a homogenous In S 2 3
layer is produced consecutively by the Spray-ILGAR process. The
ZnS reduces the recombination of the charge carriers at the
absorber/buffer heterointerface which is one important position
for performance loss in the chalcopyrite cells. The In S 2 3
in-between and on top of the ZnS dots is necessary for the charge
carrier transport as ZnS has poor conductivity. The optimal ZnS
dot density, In S thickness and process temperature with respect
2 3
to optimum solar cell performance are investigated. Moreover,
different In precursor solutions and different ZnS nanodot
deposition methods are studied and compared. As compared to a
pure In S buffered cell, the solar cell efficiency with
2 3
nano-ZnS/In S buffer layer could be improved by about 1%
2 3
absolutely upto 15.7%.
Keywords: ZnS nanodots; Spray-ILGAR; buffer layer; thin film
solar cells; passivation;
4 th EucheMs chemistry congress
P - 0 7 2 0
SeLf-ASSeMBLed tetrAGonAL PriSMAtiC
nAnoCAGe CAPABLe of SeLeCtiveLy interACt
with Pi-AnioniC SuBStrAteS
C. GArCiA-SiMon 1 , L. GóMez 1 , i. GArCiA-BoSCh 1 ,
x. riBAS 1 , M. CoStAS 1
1 University of Girona, Departament de Química Inorganica,
Girona, Spain
The development of functional nanosized molecules has
gained relevance thanks to the straightforward nature of the
metal-directed supramolecular synthetic approach. In previous
work we reported the use of macrocyclic dicopper(II) complexes
as metal-organic molecular clips capable of self-assembling at
room temperature with different di- tri- and tetracarboxylate
linkers to yield nanomolecular 2D rectangles, and polyfunctional
3D trigonal prisms. [1, 2, 3] Among the various systems developed
so far, discrete nanosized cage-like molecules are of particular
interest for the implementation of specific functions because they
provide an inner cavity that can be filled with functional guest
molecules when brought together in solution. [4]
In this work we report the preparation of a new nanocapsule
with A B tetragonal prismatic geometry (where A corresponds to
4 2
dipalladium macrocyclic complexes, and B corresponds
to the tetraanionic form of palladium 5,10,15,20-tetrakis(4-
-carboxyphenyl)-porphyrin). The large inner void space of the
obtained structure and the supramolecular affinity for guest
molecules towards porphyrin-based hosts converts this
nanomolecular 3D structure in a good candidate for host-guest
chemistry. The interaction between the nanocage and different
guest molecules has been studied by means of NMR, UV-vis,
ESI-MS and DOSY experiments. Selective molecular recognition
has been found for anionic, planar-shaped p-guests, in contrast to
the absence of interaction for neutral aromatic or cationic
substrates. Moreover using macrocycles of different lengths, we
are able to tune the cage dimensions to accommodate guests of
different sizes. [5]
The simplicity in the synthesis developed for the obtention
of these complex architectures represents a step forward for the
development of polyfunctional supramolecular nanovessels, with
multiple applications.
references:
1. A. Company et al., Inorg. Chem. 2006, 45, 2501–2508
2. L. Gómez,et al., Chem. Commun. 2007, 4410-4412
3. A. Company et al., Dalton Trans., 2008, 1679–1682
4. Guido H. Clever et al., Inorg Chem. 2011, 50, 4689-4691
5. M. Fujita et al., Acc. Chem. Res. 2005, 38, 371-380
Keywords: supramolecular chemistry; Nanostructures;
Receptors; Anions; Palladium;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc