Modulating Co-catalyst/Facet Junction for Enhanced Photoelectrochemical Water Splitting

Abstract

Rational construction of electric field via assembling appropriate co-catalysts on anisotropic facets is of great significance for improving the photogenerated charge separation efficiency. However, this strategy usually gives rise to Fermi-level pinning which is not contributive to the charge separation but deleterious to the photoelectrochemical performance through consuming the measurable photovoltage. Herein, we demonstrate that manganese dioxide electrodeposited on the (111) facet of titanium dioxide nanorods could tremendously boost the catalytic activity of pristine photoanode via a stronger interface electric field and less photovoltage decay compared with the counterpart grown on the (110) facet. A photocurrent density of 1.65 mA·cm–2 at 1.23 V (vs reversible hydrogen electrode), nearly the theoretical maximum of titanium dioxide, is achieved by the optimum photoanode with an extremely high separation efficiency of 95.15%. This study offers more in-depth insights into the design of carrier separation strategy through loading co-catalysts on different substrate surfaces for more efficient solar energy conversion.

Advanced oxygen evolution reaction catalysts for solar-driven photoelectrochemical water splitting

“…83 Min et al demonstrated that the formed junction between MnO 2 and the (111) plane of TiO 2 could provide a stronger interface electric eld for boosting the catalytic activity owing to the betting energy levels. 84 Although the above strategies have achieved a favourable effect to some This journal is © The Royal Society of Chemistry 2023 extent, the barrier of charge transfer cannot be completely removed.…”

Single-atomic ruthenium dispersion promoting photoelectrochemical water oxidation activity of CeOx catalysts on doped TiO2 nanorod photoanodes

“…oxides, hydroxides, and layered double hydroxides have exhibited signicant promise in improving the catalytic activity of TiO 2 nanostructures. 5,7,10,11,[15][16][17] The mixed transition metal oxidebased OECs incorporated with TiO 2 boost the electrical conductivity and enhance active sites for the OER, leading to improved PEC activity. 7,15 The OECs also reduce the water oxidation overpotential, efficiently drive the hole transfer from the photo harvester to the catalysts, and enhance the photoinduced charge carrier separation, resulting in enhanced surface OER of the TiO 2 photoanodes.…”

“…7,15 The OECs also reduce the water oxidation overpotential, efficiently drive the hole transfer from the photo harvester to the catalysts, and enhance the photoinduced charge carrier separation, resulting in enhanced surface OER of the TiO 2 photoanodes. 5,10,11,[15][16][17] Recently, single-atom catalysts (SACs) have emerged as successful catalysts to enhance the kinetics of the OER/hydrogen evolution reaction (HER) for water splitting by reducing the utilization of precious metal catalysts. [18][19][20][21] Both the noble metal and nonnoble metalbased SACs have been directly dispersed on the TiO 2 photo harvester to maximize the catalytic efficiency of the isolated metal atoms and to modify the electronic structure of the material.…”

Efficient photoanode with a MoS2/TiO2/Au nanoparticle heterostructure for ultraviolet-visible photoelectrocatalysis

“…These approaches encompass heteroatom doping [7,8], morphology manipulation [9,10], quantum dot sensitization [11], and so forth. While these methods effectively broaden TiO 2 working spectrum and consequently enhance photocurrent, the efficiency of charge separation remains relatively constrained, necessitating further advancements in TiO 2 -based photoanodes [12].…”