Selective placement of modifiers on hematite thin films for solar water splitting

Abstract

The design of nanostructured materials for photoelectrochemical water splitting relies on a detailed understanding of the reactional bottlenecks. For hematite, a model system for photoanodes, the challenges concern poor charge...

Dual modification on hematite to minimize small polaron effects and charge recombination for sustainable solar water splitting

“…Finally, one can see from Sn 4+ EDS mapping that no significant amount of tin diffused to the photoabsorbing hematite layer, supporting negligible interferences from Sn 4+ self-diffusion in the electrochemical measurements. 14…”

“…Pires et al demonstrated an improvement in PEC performance by using Ga 3+ as a lattice dopant and Hf 4+ as an interfacial dopant. 14 Although they achieved a sevenfold increase in photocurrent in comparison to pristine hematite, here we draw the hypothesis that a knowledgeable selection of the dopants for both the crystalline lattice and interfaces can yield a more significant performance improvement by thoroughly exploring the novel synthetic protocol while also considering sustainability matters.…”

“…Recently, Pires et al explored the possibility of concomitantly manipulating the crystalline lattice and interfaces in a single precursor solution. 14 Dual modification of oxides has been reported focusing on the synergistic influence of ions with mixed valence states. 15–26 However, the PPS synthesis strategy can be used to specifically favor dopant solid-solution or dopant interfacial segregation by manipulating the chemistry of a polymeric solution.…”

Enhancing photocatalytic efficiency with hematite photoanodes: principles, properties, and strategies for surface, bulk, and interface charge transfer improvement

“…RHE. Another new and more effective strategy, introduced by Pires et al 125 involves the selective placement of modifiers. Here, they present a novel approach using a single polymeric precursor solution for the design of α-Fe 2 O 3 with synergistic bulk and interfacial engineering involving Ga 3+ , Hf 4+ , and NiFeO x .…”