Co-doped titanium oxide foam and water disinfection device
A quaternary oxide foam, comprises an open-cell foam containing (a) a dopant metal, (b) a dopant nonmetal, (c) titanium, and (d) oxygen. The foam has the advantages of a high surface area and a low back pressure during dynamic flow applications. The inactivation of Escherichia coli ( E. coli ) was demonstrated in a simple photoreactor.
1. A quaternary oxide foam, comprising an open-cell foam comprising titanium oxide containing:
(a) a dopant metal comprising palladium,
(b) a dopant nonmetal,
(c) titanium, and
(d) oxygen,
wherein the dopant metal is present at a concentration of at most 2 wt. %, and wherein the open-cell foam comprises a pore size distribution having at least two peaks.
2. The quaternary oxide foam of claim 1 , wherein the atomic ratio of titanium, oxygen and dopant nonmetal is 1:0.5-1.99:0.01-1.5.
3. The quaternary oxide foam of claim 1 , wherein the atomic ratio of titanium, oxygen and dopant nonmetal is 1:1.9-1.99:0.01-0.1.
4. The quaternary oxide foam of claim 1 , wherein the dopant nonmetal is nitrogen.
5. The quaternary oxide foam of claim 4 , wherein the foam has a porosity of at least 90%.
6. The quaternary oxide foam of claim 4 , wherein the foam has a porosity of 90-98%.
7. The quaternary oxide foam of claim 4 , wherein the foam is monolithic with a longest dimension of at least 0.1 mm.
8. The quaternary oxide foam of claim 4 , wherein the foam is monolithic with a longest dimension of at least 0.5 mm.
9. The quaternary oxide foam of claim 4 , wherein the foam is monolithic with a longest dimension at least 1 mm.
10. The quaternary oxide foam of claim 4 , wherein visible light will lose less than 75% of its intensity when passed through 1 cm of the foam.
11. The quaternary oxide foam of claim 4 , wherein visible light will lose less than 50% of its intensity when passed through 1 cm of the foam.
12. A method of catalyzing a reaction, comprising:
exposing a quaternary oxide foam to light; and
contacting the quaternary oxide foam with a reactant, to form a product of the reaction;
wherein the quaternary oxide foam comprises an open-cell foam comprising titanium oxide containing:
(a) a dopant metal comprising palladium,
(b) a dopant nonmetal,
(c) titanium, and
(d) oxygen,
wherein the dopant metal is present at a concentration of at most 2 wt. %, and wherein the open-cell foam comprises a pore size distribution having at least two peaks.
13. A reactor, comprising:
(i) an inlet,
(ii) an outlet, and
(iii) a catalyst, fluidly connected to the inlet and the outlet,
wherein the catalyst comprises a quaternary oxide foam comprising an open-cell foam comprising titanium oxide containing:
(a) a dopant metal comprising palladium,
(b) a dopant nonmetal,
(c) titanium, and
(d) oxygen,
wherein the dopant metal is present at a concentration of at most 2 wt. %, and wherein the open-cell foam comprises a pore size distribution having at least two peaks.
14. A quaternary oxide foam, prepared by a method comprising:
impregnating an open-cell template foam with a liquid mixture; and
heating the impregnated open-cell foam, to form the quaternary oxide foam comprising titanium dioxide including a dopant metal and a dopant nonmetal;
wherein the liquid mixture contains
(a) the dopant metal comprising palladium,
(b) the dopant nonmetal, and
(c) titanium,
wherein the dopant metal is present in the quaternary oxide foam at a concentration of at most 2 wt. %, and wherein the open-cell foam comprises a pore size distribution having at least two peaks.