A combustion system having improved mercury collection. The system includes a combustion chamber for burning a fuel containing mercury, whereby burning produces a flue gas stream containing mercury and a device for removing mercury from the flue gas stream. The device includes a thermopolymer substrate; and a mercury-receptor attached to the substrate. In one embodiment, the system may further include a collector downstream of the device for collecting the mercury attached to the thermopolymer. The inventions further include alternative methods of mercury removal and preparation of the polymer substrate.