Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pore morphology evolution and atom distribution of doped Fe2O3 foams
  developed by freeze-casting after redox cycling   Chemical looping water splitting systems operate at relatively high
temperatures (450-800 degree C) to produce, purify, or store hydrogen by the
cyclic reduction and oxidation (redox) of a solid oxygen carrier. Therefore, to
improve long-term operation, it is necessary to develop highly stable oxygen
carriers with large specific surface areas. In this work, highly interconnected
doped Fe2O3 foams are fabricated through the freeze-casting technique, and the
aid of a submicrometric camphene-based suspension to prevent Fe sintering and
pore clogging during redox operation. The influence of the dopant elements (Al
and Ce) over the pore morphology evolution, and redox performances are
examined. The use of an Fe2O3 porous structure with initial pore size above 100
microns shows a significant reduction of the sample densification, and the
addition of Al2O3 by the co-precipitation process proves to be beneficial in
preventing the generation of a core-shell structure following redox processing.

9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ