Yes. You can claim the business use percentage if it is not reimbursed (or won't be reimbursed).
If it is for a job for with he works as an "employee"
receiving a W-2, and they are not reimbursed to you, then you can deduct them
as an Unreimbursed Employee Business Form 2106. It goes on
Schedule A Itemized Deductions in the Misc section subject to a 2% of Adjusted
Gross Income threshold. That means his unreimbursed employee expenses over 2% of Adjust Gross Income will be included as a deduction.
Where do I enter job-related employee expenses? (Form
2106)
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