Surface structural design of selective emitter for methane steam reforming

We performed structural optimization of a selective emitter with two-dimensional silicon based gratings coated by platinum as a thermal radiator to promote methane steam reforming reaction. The structural parameters were optimized by numerical calculation to radiate high thermal power in a vibrational absorption band of methane molecule at 3.3 μm. Optical property of the fabricated optimum selective emitter with periodicity Λ = 2.6 μm found that the emission peak was resonant with this absorption band. The amount of hydrogen produced by the methane steam reforming process using the optimized selective emitter became four times greater than that obtained by the flat emitter.