Hexahedron Prism-Anchored Octahedronal CeO₂: Crystal Facet-Based Homojunction Promoting Efficient Solar Fuel Synthesis

Abstract

An unprecedented, crystal facet-based CeO2 homojunction consisting of hexahedron prism-anchored octahedron with exposed prism surface of {100} facets and octahedron surface of {111} facets was fabricated through solution-based crystallographic-oriented epitaxial growth. The photocatalysis experiment reveals that growth of the prism arm on octahedron allows to activate inert CeO2 octahedron for an increase in phototocatalytic reduction of CO2 into methane. The pronounced photocatalytic performance is attributed to a synergistic effect of the following three factors: (1) band alignment of the {100} and {111} drives electrons and holes to octahedron and prism surfaces, respectively, aiming to reach the most stable energy configuration and leading to a spatial charge separation for long duration; (2) crystallographic-oriented epitaxial growth of the CeO2 hexahedron prism arm on the octahedron verified by the interfacial lattice fringe provides convenient and fast channels for the photogenerated carrier transportation between two units of homojuntion; (3) different effective mass of electrons and holes on {100} and {111} faces leads to high charge carrier mobility, more facilitating the charge separation. The proposed facet-based homojunction in this work may provide a new concept for the efficient separation and fast transfer of photoinduced charge carriers and enhancement of the photocatalytic performance.

Continuous wet-process growth of ZnO nanoarrays for wire-shaped photoanode of dye-sensitized solar cell

“…The continuous reactor is superior to the traditional batch-type reactor in fabricating wire-shaped ZnO-type photoanode for wearable solar cells or other optoelectronic devices. As a type of scalable and easily-controlled synthesis process, it is also applicable for the growth of other semiconductive nano materials, which should be of interest in other fields, such as photocatalysis and electro-catalysis [33][34][35]. Besides, our new growth strategy is compatible with most previously-reported works.…”

Controlled synthesis of m-BiVO4 dendrites for enhanced photocatalytic activity

“…55% of RhB was removed when the photocatalytic degradation time is 240 min, and the degradation rate of the counterpart is 40%. The excellent photocatalytic activity of the as-prepared m-BiVO 4 dendrites might be contributed to the special morphology which could effectively enhance the utilization of light [12][13][14][15][16][17]. The inset in Fig.…”

Facet‐Engineered Surface and Interface Design of Photocatalytic Materials

“…Thus the artificial synthesis of crystal facet‐based homojunctions offers an alternative approach to achieve the synergism between two facets through spatial charge separation. An excellent demonstration is the CeO 2 homojunction consisting of hexahedron prism‐anchored octahedron fabricated through crystallographic‐oriented epitaxial growth 97. The hexahedron prism‐anchored CeO 2 octahedrons and bare CeO 2 octahedrons were selectively obtained by controlling the addition of phosphate ions (Figure 11g,h).…”