Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modelling Grain Boundaries in Polycrystalline Halide Perovskite Solar
  Cells   Solar cells are semiconductor devices that generate electricity through
charge generation upon illumination. For optimal device efficiency, the
photo-generated carriers must reach the electrical contact layers before they
recombine. A deep understanding of the recombination process and transport
behavior is essential to design better devices. Halide perovskite solar cells
are commonly made of a polycrystalline absorber layer, but there is no
consensus on the nature and role of grain boundaries. This review paper
concerns theoretical approaches for the investigation of extended defects. We
introduce recent computational studies on grain boundaries, and their influence
on point defect distributions, in halide perovskite solar cells. We conclude
the paper with discussion of future research directions.

32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
2
The categories of this paper are: math