Sir Martyn Poliakoff, is a British chemist, working on fundamental chemistry, and on developing environmentally acceptable processes and materials. The core themes of his work are supercritical fluids, infrared spectroscopy and lasers. He is a research professor in chemistry at the University of Nottingham. As well as carrying out research at the University of Nottingham, he is a lecturer, teaching a number of modules including green chemistry.

A supercritical fluid (SCF) is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist, but below the pressure required to compress it into a solid. It can effuse through porous solids like a gas, overcoming the mass transfer limitations that slow liquid transport through such materials. SCF are superior to gases in their ability to dissolve materials like liquids or solids. Also, near the critical point, small changes in pressure or temperature result in large changes in density, allowing many properties of a supercritical fluid to be "fine-tuned".