Answered by Sayyidi Habib Umar bin Hafiz (may Allah protect him and benefit us by him)
What can a student recite in order to keep his intentions pure and to banish laziness and procrastination at the time of study?
You should read the merits of seeking knowledge. There is a very useful section on this in the introduction to Imam al-Nawawi’s al-Majmu’. You should also study the biographies of those who exerted great efforts in seeking knowledge.
Recite 100 times a day:
هُوَ اللهُ الَّذي لا إِلهَ إِلا هو عَالِمُ الغَيْبِ والشَّهادَةِ هُوَ الرَّحْمَنُ الرَّحِيم
Huwa Allāhu’lladhī la ilāha illā hu, ‘Ālimu’l ghaybi w’al-shahādah, Hu al-raḥmānu’ raḥīm
He is Allah, there is no god other than Him, knower of the unseen and the seen, He is the All-Compassionate, the All-Merciful (59:22)