if you mean solid surface material, I think the SST plates or tubes are the applicable materials and most of investigations dealt with this materials. if you do not mean that? please, specify your question. thanks
Even though you need to clarify your question, my suggestion would be to use water (deionised or pure) in terms of heat transfer fluids, while Rayleigh-Benard (RB) cells are ideal systems to study turbulence (soft and hard turbulent states, depending on the Rayleight number and geometry of RB cell). There are quite a few studies available in the literature using these key words.