Contracted forms (contractions) are a typical feature of informal language and are usually avoided in academic writing.
Using contractions in a text tends to alter the tone of the text and make it more informal. You may find some in published articles, but you should avoid them.

Here are some examples:

Contracted form Full form

won’t will not

can’t cannot

don’t do not

isn’t is not

. . . not . . . any no

. . . not . . . much little

. . . not . . . many few

Compare the following examples:

1a) The import figures won’t decrease . . .

1b) The import figures will not decrease . . .

2a) The study didn’t yield any new results.

2b) The study yielded no new results.

3a) The department doesn’t have a solution.

3b) The department has no solution.

4a) The article didn’t arouse much interest.

4b) The article aroused little interest.