Probably not a good idea: "Vantablack surface is easily damaged by any direct impact or abrasion". From [1]. People would be touching the walls all the time.

Probably not a good idea: "Vantablack surface is easily damaged by any direct impact or abrasion". From [1]. People would be touching the walls all the time. 1 - https://www.surreynanosystems.com/vantablack/faqs https://www.surreynanosystems.com/vantablack/faqs