Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Halogenated MXenes with Electrochemically Active Terminals for High
  Performance Zinc Ion Batteries   The class of two-dimensional metal carbides and nitrides known as MXenes
offer a distinct manner of property tailoring for a wide range of applications.
The ability to tune the surface chemistry for expanding the property space of
MXenes is thus an important topic, although experimental exploration of new
surface terminals remains a challenge. Here, we synthesized Ti3C2 MXene with
unitary, binary and ternary halogen terminals, e.g. -Cl, -Br, -I, -BrI and
-ClBrI, to investigate the effect of surface chemistry on the properties of
MXenes. The electrochemical activity of Br and I element result in the
extraordinary electrochemical performance of the MXenes as cathodes for aqueous
zinc ion batteries. The -Br and -I containing MXenes, e.g. Ti3C2Br2 and
Ti3C2I2, exhibit distinct discharge platforms with considerable capacities of
97.6 mAh g-1 and 135 mAh g-1. Ti3C2(BrI) and Ti3C2(ClBrI) exhibit dual
discharge platforms with capacities of 117.2 mAh g-1 and 106.7 mAh g-1. In
contrast, the previously discovered MXenes Ti3C2Cl2 and Ti3C2(OF) exhibit no
discharge platforms, and only ~50% of capacities and energy densities of
Ti3C2Br2. These results emphasize the effectiveness of the Lewis-acidic-melt
etching route for tuning the surface chemistry of MXenes, and also show promise
for expanding the MXene family towards various applications.

10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga