Can we decorate our walls with Qur’anic verses like Ayatul Kursi?

Decorating the walls with Qur’anic verses, like the mosques in Makkah and Madinah and many parts of the Muslim is definitely not from the Sunnah and it is preferable not to do so. The Prophet (ﷺ) received a cloak from Yemen which was striped with nice colours, and because it caught his attention during his prayer, he gave it away. He did not want anything that would distract his attention.[1]

Similarly, some masajid have prayer rugs with many designs and pictures, and when you are standing to pray, the design may start to distract you. This is not from the Sunnah at all. If you have a prayer rug, it should just be black. We have lost the whole concept of what concentration in Salah is about, and we have been overcome by decoration, the love of beautification.

Reference:

[1] Bukhari (373) and Muslim (556)