I am using Drupal 8 and I used the Views data export module which handles XML and JSON as exporting formats.
Is there any way to export data in Excel format?
As an alternative to the module you are using, try the PHPExcel module. Some details about it (from its project page):
The PHPExcel module allows developers to export/import data to/from real Excel files.
The idea behind this module is to have a single module for handling the export or import of Excel files, instead of multiple modules handling specific cases.
The module provides no functionality as-is (the .module file is as good as empty). The phpexcel.inc file must be included to use the export or import functions in your own module.