Microwave-assisted low temperature fabrication of nanostructured α-Fe2O3 electrodes for solar-driven hydrogen generation

Electromagnetic simulation studies of microwave assisted heating for the processing of nanostructured iron oxide for solar driven water splitting

“…We showed for the first time that the conversion of iron into iron oxide using a microwave assisted process occurred at lower temperatures and at faster times than what had been previously reported [16]. It was also demonstrated that the less demanding processing conditions associated with the microwave approach combined with the specific advantage of rapid heating and cooling.…”

“…3 improved PEC performance [16,23]. We showed for the first time that the conversion of iron into iron oxide using a microwave assisted process occurred at lower temperatures and at faster times than what had been previously reported [16].…”

“…For example, as shown in Fig. 1, the highest photocurrent density at 0.55 V vs. V Ag/AgCl , before the dark current onset, was ~400 μA.cm -2 for the films annealed at 250 °C for 15 minutes using microwave irradiation while conventional annealing at the same temperature resulted in samples with negligible (3 μA.cm-2) photoactivity [16].…”

“…It was also demonstrated that the less demanding processing conditions associated with the microwave approach combined with the specific advantage of rapid heating and cooling. The performance of microwave-prepared films surpassed that of the samples annealed conventionally while a total energy savings of >60% was achieved [16]. For example, as shown in Fig.…”

“…higher photocurrent density) was attributed to the following factors: i) improved surface properties of microwave heated films, i.e. less defective oxygen sub-lattice of hematite hence less surface recombination [23], ii) the retained nanostructure and minimised grain coalescence as a result of lower processing temperatures and rapidity of the process [16]. However, the interaction of electromagnetic (EM) field with the nanostructured film is not completely understood.…”