Although bismuth vanadate -(BiVO4) has been promising as photoanode material for photoelectrochemical water splitting, its charge recombination issue by short charge diffusion length has led to various studies about heterostructure photoanodes. As a hole blocking layer of -BiVO4, titanium dioxide -(TiO2) has been considered unsuitable because of its relatively positive valence band edge and low electrical conductivity. Herein, a crystal facet engineering of -TiO2 nanostructures is proposed to control band structures for the hole blocking layer of -BiVO4 nanodots. We design two types of -TiO2 nanostructures, which are nanorods (NRs) and nanoflowers (NFs) with different (001) and (110) crystal facets, respectively, and fabricate -BiVO4/TiO2 heterostructure photoanodes. The -BiVO4/TiO2 NFs showed 4.8 times higher photocurrent density than the -BiVO4/TiO2 NRs. Transient decay time analysis and time-resolved photoluminescence reveal the enhance?ment is attributed to the reduced charge recombination, which is originated from the formation of type Ⅱ band alignment between -BiVO4 nanodots and -TiO2 NFs. This work provides not only new insights into the interplay between crystal facets and band structures but also important steps for the design of highly efficient photoelectrodes.

Mi Gyoung Lee;Jin Wook Yang;Hoonkee Park;Cheon Woo Moon;Dinsefa M.Andoshe;Jongseong Park;Chang?Ki Moon;Tae Hyung Lee;Kyoung Soon Choi;Woo Seok Cheon;Jang?Joo Kim;Ho Won Jang

Department of Materials Science and Engineering,Research Institute of Advanced Materials,Seoul National University,Seoul 08826,Republic of Korea;Department of Chemistry and Nanoscience,Ewha Womans University,Seoul 03693,Republic of Korea;National Research Facilities and Equipment Center,Korea Basic Science Institute,Daejeon 34133,Republic of Korea;Advanced Institute of Convergence Technology,Seoul National University,Suwon 16229,Republic of Korea

纳微快报（英文）

[1]Mi Gyoung Lee;Jin Wook Yang;Hoonkee Park;Cheon Woo Moon;Dinsefa M.Andoshe;Jongseong Park;Chang?Ki Moon;Tae Hyung Lee;Kyoung Soon Choi;Woo Seok Cheon;Jang?Joo Kim;Ho Won Jang-.Crystal Facet Engineering of -TiO2 Nanostructures for Enhancing Photoelectrochemical Water Splitting with -BiVO4 Nanodots)[J].纳微快报（英文）,2022(03):201-215

Nanodots

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