Keep my 12mo emergency fund in a RothIRA? Tax efficiency question

Basic premise: I work in a volatile industry and want to keep 9-12mo of monthly expenses on hand in a fairly liquid pot. A little appreciation is nice, but theres very little risk appetite for this pot.

Right now I keep that amount in a HYSA earning 4%APY, but the tax drag on interest is a PITA.

What if instead I invest the amount in the HYSA into VOO (or similar) in my taxable brokerage account, and instead keep the 9-12mo emergency fund as CDs in my RothIRA. The RothIRA would accumulate interest tax free, but the principal should be withdrawable tax free.