Details
| Original language | English |
|---|---|
| Pages (from-to) | 9208-9217 |
| Number of pages | 10 |
| Journal | Chemistry of materials |
| Volume | 29 |
| Issue number | 21 |
| Publication status | Published - 28 Sept 2017 |
Abstract
Porous architectures of noble metal nanocrystals are promising for many catalytic as well as for fuel cell applications. Here we present the synthesis of porous, extremely lightweight aerogels of self-supported Pt nanocubes and nanospheres by direct destabilization from nonpolar colloidal solution using hydrazine monohydrate (N2H4·H2O) as gelation reagent. The template-free voluminous lyogels of the Pt nanocrystals are converted to macroscopic solid aerogel monoliths by supercritical drying. The aerogels from Pt nanocubes mostly exhibit (100) as the exposed crystal facets throughout the entire monolithic surface, while the aerogels from quasi-spherical Pt nanocrystals exhibit many crystal facets such as (111) and (100). Furthermore, the aerogels exhibit remarkably low densities of ∼0.19 g cm-3 ± 0.038 g cm-3 (∼0.9% of bulk Pt) and a specific surface area in the range of ∼6400-7000 m2 mol-1. The nanocube gels show better catalytic performance than the nanosphere gels when employed for asymmetric hydrogenation reaction, which is exemplarily shown for 4,4-dimethyldihydrofuran-2,3-dione to d-/l-pantolactone conversion with an excess of 9% for the d-enantiomer. Owing to their high specific surface area and certain type of exposed crystal facets, Pt aerogels developed here are highly promising for possible future applications in facet selective catalytic reactions.
ASJC Scopus subject areas
- Chemistry(all)
- General Chemistry
- Chemical Engineering(all)
- General Chemical Engineering
- Materials Science(all)
- Materials Chemistry
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Chemistry of materials, Vol. 29, No. 21, 28.09.2017, p. 9208-9217.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Porous Aerogels from Shape-Controlled Metal Nanoparticles Directly from Nonpolar Colloidal Solution
AU - Naskar, Suraj
AU - Freytag, Axel
AU - Deutsch, Jens
AU - Wendt, Natalja
AU - Behrens, Peter
AU - Köckritz, Angela
AU - Bigall, Nadja C.
N1 - Funding information: N.B., S.N., A.F. are grateful for financial support from the German Federal Ministry of Education and Research (BMBF) within the framework of the program NanoMatFutur, support code 03 × 5525. We would like to thank Tanja Heemeier, Mandy Jahns, and Alexander Mohmeyer from Institute for Inorganic Chemistry (LUH) for the help with FTIR measurements. We acknowledge Dr. Dirk Dorfs and Dominik Hinrichs from Institute of Physical Chemistry and Electrochemistry (LUH) for helpful discussions. The authors would also like to thank the Laboratory for Nano and Quantum Engineering (LNQE).
PY - 2017/9/28
Y1 - 2017/9/28
N2 - Porous architectures of noble metal nanocrystals are promising for many catalytic as well as for fuel cell applications. Here we present the synthesis of porous, extremely lightweight aerogels of self-supported Pt nanocubes and nanospheres by direct destabilization from nonpolar colloidal solution using hydrazine monohydrate (N2H4·H2O) as gelation reagent. The template-free voluminous lyogels of the Pt nanocrystals are converted to macroscopic solid aerogel monoliths by supercritical drying. The aerogels from Pt nanocubes mostly exhibit (100) as the exposed crystal facets throughout the entire monolithic surface, while the aerogels from quasi-spherical Pt nanocrystals exhibit many crystal facets such as (111) and (100). Furthermore, the aerogels exhibit remarkably low densities of ∼0.19 g cm-3 ± 0.038 g cm-3 (∼0.9% of bulk Pt) and a specific surface area in the range of ∼6400-7000 m2 mol-1. The nanocube gels show better catalytic performance than the nanosphere gels when employed for asymmetric hydrogenation reaction, which is exemplarily shown for 4,4-dimethyldihydrofuran-2,3-dione to d-/l-pantolactone conversion with an excess of 9% for the d-enantiomer. Owing to their high specific surface area and certain type of exposed crystal facets, Pt aerogels developed here are highly promising for possible future applications in facet selective catalytic reactions.
AB - Porous architectures of noble metal nanocrystals are promising for many catalytic as well as for fuel cell applications. Here we present the synthesis of porous, extremely lightweight aerogels of self-supported Pt nanocubes and nanospheres by direct destabilization from nonpolar colloidal solution using hydrazine monohydrate (N2H4·H2O) as gelation reagent. The template-free voluminous lyogels of the Pt nanocrystals are converted to macroscopic solid aerogel monoliths by supercritical drying. The aerogels from Pt nanocubes mostly exhibit (100) as the exposed crystal facets throughout the entire monolithic surface, while the aerogels from quasi-spherical Pt nanocrystals exhibit many crystal facets such as (111) and (100). Furthermore, the aerogels exhibit remarkably low densities of ∼0.19 g cm-3 ± 0.038 g cm-3 (∼0.9% of bulk Pt) and a specific surface area in the range of ∼6400-7000 m2 mol-1. The nanocube gels show better catalytic performance than the nanosphere gels when employed for asymmetric hydrogenation reaction, which is exemplarily shown for 4,4-dimethyldihydrofuran-2,3-dione to d-/l-pantolactone conversion with an excess of 9% for the d-enantiomer. Owing to their high specific surface area and certain type of exposed crystal facets, Pt aerogels developed here are highly promising for possible future applications in facet selective catalytic reactions.
UR - http://www.scopus.com/inward/record.url?scp=85034059019&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.7b03088
DO - 10.1021/acs.chemmater.7b03088
M3 - Article
AN - SCOPUS:85034059019
VL - 29
SP - 9208
EP - 9217
JO - Chemistry of materials
JF - Chemistry of materials
SN - 0897-4756
IS - 21
ER -