This kind of advises in the opposite direction, but do you think that you could give yourself a break in the afternoon and study in the morning? So when you get home, maybe fit in a small homework task or something, but go easy on yourself, and wake up early in the morning for homework. I didn't do this all year, only towards the end where my exams were, and after about a week of trial, I realised I studied best in the morning. Maybe part of the reason you struggle to study in the afternoon is because you know you're too tired, so you're working against your mind. But if you don't beat yourself up over it and let yourself enjoy the time, maybe that cycle of negative "I can't find time" might feel a little more relaxed.
For me, when I had days when I was really tired but kept forcing myself to study, I'd not get much done and I'd be really hard on myself for it and the cycle would continue. But when I'd be like, "hey, you're tired, give it a rest" then half the negativity would subside and I'd be much more resilient and back at it the next day. Obviously your situation is different because you're feeling it everyday, but maybe morning study is best for you, and using recess and lunch for study as well (I did this) so that when you go home, you know you've got the afternoon to yourself.