TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Materials: The polyoxometalate further comprises addenda-elements comprising a transition metal and hetero-elements from the International Union of Pure and Applied Chemistry (IUPAC) groups 13-16. The addenda-element comprises vanadium, tantalum, molybdenum, or tungsten. The hetero-element comprises phosphorus or silicon. The support substance may comprise carbon black. The support substance and polyoxometalate are chemically bonded to the functional entity. The functional entity comprises silane, phosphate, phosphate ester, phosphonate, phosphonate ester, phosphinate, phosphinate ester, phosphonite, phosphinite, phosphine, tin-containing entity, germanium-containing entity, titanium-containing entity, and/or zinc-containing entity. The chemical bond linking the polyoxometalate and functional entity comprises oxygen-silicon (-O-Si-), oxygen-phosphorus (-O-P-), oxygen-tin (-O-Sn-), oxygen-titanium (-O-Ti-), oxygen-germanium (-O-Ge-), or oxygen-zinc (-O-Zn-). The chemical bond linking the support substance and functional entity comprises -CH2, -CHR1-, -CR1R2-, -S-, -NH-, -NR1-, -NN-, -CH2CH2-, -C(=O)O-, or -O-.R1, R2=alkyl or aryl.Preferred Properties: The addenda-element has an ionic radius of 0.4-0.9 Angstrom , an ionic charge of + 2 to + 8, and/or a d0 or d1 electronic configuration. The support substance comprises particles having an average diameter of 1-100 nm. Preferred Composition: The immobilized polyoxometalate comprises 0.5-90 wt.% polyoxometalate anion and 10-99 wt.% support substance.    TECHNOLOGY FOCUS - METALLURGY - Preferred Materials: The support substance may comprise platinum black, metallic black or platinum alloy black. The catalyst support substance comprises platinum black or reduced platinum salt.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Materials: The electrolyte membrane comprises a perfluorosulfonated ionomer electrolyte membrane. The polyoxometalate electrode comprises an anode or cathode contacting methanol, dimethyl ether or perfluorosulfonated ionomer undergoing an electrochemical reaction to produce 0.4-2 mu g/day/cm2 fluoride.    TECHNOLOGY FOCUS - POLYMERS - Preferred Materials: The conductive backing comprises a graphitized carbon fiber-based nonwoven, paper or felt. EXAMPLE - Sodium tungstate dihydrate (182.1 g) was dissolved in boiling deionized water (300 mL) and added dropwise with 4 M hydrochloric acid (165 mL) in a 30 minute period. A solution of metasilicate (11 g sodium metasilicate silicate containing 44-47% silica dissolved in 100 mL deionized water) was quickly added. The pH was adjusted to 5.4. The solution was kept boiling for 1 hour and then cooled to room temperature and filtered. Potassium chloride (150 g) was added to the filtrate and the resulting solution was stirred for 30 minutes. The product was washed with 1 M potassium chloride solution (2x50 mL), then with ice cold water (50 mL) and dried in air. Yield was 136.1 g (84.5%).