Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rapid one-step synthesis and compaction of high-performance n-type
  Mg3Sb2 thermoelectrics   n-type Mg3Sb2-based compounds are emerging as a promising class of low-cost
thermoelectric materials due to their extraordinary performance at low and
intermediate temperatures. However, so far high thermoelectric performance has
merely been reported in n-type Mg3Sb2-Mg3Bi2 alloys with a large amount of Bi.
Moreover, current synthesis methods of n-type Mg3Sb2 bulk thermoelectrics
involve multi-step processes that are time- and energy-consuming. Here we
report a fast and straightforward approach to fabricate n-type Mg3Sb2
thermoelectrics using spark plasma sintering, which combines the synthesis and
compaction in one step. Using this method, we achieve a high thermoelectric
figure of merit zT of ~0.4-1.5 at 300-725 K in n-type (Sc, Te)-doped Mg3Sb2
without alloying with Mg3Bi2. In comparison with the currently reported
synthesis methods, the complexity, process time, and cost of the new method are
significantly reduced. This work demonstrates a simple, low-cost route for the
potential large-scale production of n-type Mg3Sb2 thermoelectrics.

11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs