We recently had a bit of an issue with one of our cats deciding she didn't want to use the cat litter. I'll give her her due, she was really careful to pick her alternative place (a small plant pot sized bucket was her initial choice) but there was obviously a problem.
A problem that was happily solved by giving her her own cat bog to use, AND a new type of litter.
The experimental new litter is not only a hit with her but also with me.
It has SUPERB clumping properties, really easy to scoop and bits don't fall off whilst transferring it to the biodegradeable bag, (which I twist and put in the bucket so I can use each bag more efficiently) and it seems to take care of that horrible "ammonia hit" one can get when scooping, and replace it with a really quite pleasant coco-nutty sort of smell, making the job FAR less unpleasant to do.
It is called "Catit" brand "Go natural" pea husk clumping cat litter, and a box is probably expensive, but it IS efficient and has improved the quality of my life and the air quality in our house.