This invention relates generally to composite materials and to devices which may alter fluid parameters. Devices incorporating the composite materials of the invention are used to deliver, remove, and generate, fluid treatment agents, and combinations thereof. These materials and devices are applicable to many different fluid processing situations including drinking water treatment, wastewater treatment, emission treatment, pollution cleanup, and sensing fluid composition. In its more particular aspects, the invention relates to the field of composites that may be widely tailored for many different treatment applications.