Patent Number: 
Section: claims

1. A method for forming a neutron converter layer, comprising:machining an aerogel or polymer matrix to a selected converter layer size;dissolving a neutron hardening precursor in a supercritical carbon dioxide (CO2) fluid above a temperature of 31.1 degrees Celsius and a pressure of 7.29 MPa;infusing the supercritical CO2 fluid with the dissolved neutron hardening precursor into the aerogel or polymer matrix;lowering the pressure to trap the infused neutron hardening precursor in the aerogel or polymer matrix;reducing the aerogel or polymer matrix including the trapped infused neutron hardening precursor at an elevated temperature;infusing a conductive precursor into the reduced aerogel or polymer matrix; andinfusing a secondary electron emission coefficient (SEE) element precursor into the reduced aerogel or polymer matrix. 2. The method of claim 1, wherein the neutron hardening precursor is boron or gadolinium. 3. The method of claim 2, wherein the SEE element precursor is magnesium oxide or cesium iodide. 4. The method of claim 3, wherein the neutron converter layer has a high neutron absorption cross-section, a high electron emission coefficient, and a tailored resistivity. 5. A method for forming a neutron converter layer, comprising:machining an aerogel or polymer matrix to a selected converter layer size;dissolving neutron hardening precursor, a conductive precursor, and a secondary electron emission coefficient (SEE) element precursor in a supercritical carbon dioxide (CO2) fluid above a temperature of 31.1 degrees Celsius and a pressure of 7.29 MPa;infusing the supercritical CO2 fluid with the dissolved neutron hardening precursor, conductive precursor, and SEE element precursor into the aerogel or polymer matrix;lowering the pressure to trap the infused neutron hardening precursor, conductive precursor, and SEE element precursor in the aerogel or polymer matrix; andreducing the aerogel or polymer matrix including the trapped infused neutron hardening precursor, conductive precursor, and SEE element precursor at an elevated temperature. 6. The method of claim 5, wherein the neutron hardening precursor is boron or gadolinium. 7. The method of claim 6, wherein the SEE element precursor is magnesium oxide or cesium iodide. 8. The method of claim 7, wherein the neutron converter layer has a high neutron absorption cross-section, a high electron emission coefficient, and a tailored resistivity. 9. A method for forming a neutron converter layer, comprising:forming a solution of an alkoxide solution, water, alcohol, and a basic catalyst in the presence of metal precursors;adjusting a composition of the alkoxide solution, water, alcohol, and the basic catalyst to control a rate of hydrolysis and condensation and form a metalized aerogel having radiation hardened nanoparticles and secondary electron emission coefficient (SEE) nanoparticles; anddrying the metalized aerogel having radiation hardened nanoparticles and SEE nanoparticles using a supercritical carbon dioxide (CO2) fluid at a temperature of 31.1 degrees Celsius and a pressure of 7.29 MPa to form a single layer neutron converter material. 10. The method of claim 9, wherein the metal precursors are selected from the group consisting of Gd2O3, B2O3, MgO, CsI, and any combinations thereof;wherein the radiation hardened nanoparticles include boron or gadolinium, and wherein the secondary electron emission coefficient (SEE) nanoparticles include magnesium oxide or cesium iodide. 11. The method of claim 9, further comprising adding a quantity of carbon nanotubes to adjust a resistivity of the metalized aerogel having radiation hardened nanoparticles and SEE nanoparticles. 12. The method of claim 11, wherein the neutron converter layer has a high neutron absorption cross-section, a high electron emission coefficient, and a tailored resistivity.