TY - JOUR
T1 - In-situ construction of metallic Ni3C@Ni core–shell cocatalysts over g-C3N4 nanosheets for shell-thickness-dependent photocatalytic H2 production
AU - Shen, Rongchen
AU - He, Kelin
AU - Zhang, Aiping
AU - Li, Neng
AU - Ng, Yun Hau
AU - Zhang, Peng
AU - Hu, Jun
AU - Li, Xin
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/8/15
Y1 - 2021/8/15
N2 - Herein, we designed the shell-thickness-controlled Ni3C@Ni/g-C3N4 photocatalysts with intimate Schottky-junctions by an in situ high-temperature transformation strategy. Meanwhile, we found that the cocatalysts with optimized Ni shell-layer thickness of 15 nm could achieve the best visible-light photocatalytic H2-production performance of 11.28 μmolh−1, with an apparent quantum yield (AQY) of 1.49 % at 420 nm, which was 16 times higher than that of Ni3C/g-C3N4. Moreover, an excellent stability is achieved. The well-defined density functional theory (DFT) calculations indicate that the “TOP_C1” sites of Ni3C@Ni can exhibit the H adsorption and Gibbs free energies of -0.07eV and 0.18 eV, respectively, which should be hydrogen-evolution active sites instead of two “HOLLOW” sites. Interestingly, the intimate Schottky-junctions, could hinder rapid charge recombination, increase reactive sites, boost catalytic kinetics and passivate unstable surface of Ni3C, thus achieving shell-thickness-dependent hydrogen evolution. Therefore, the Ni3C@Ni core–shell cocatalysts will open a new avenue for robust solar fuel production.
AB - Herein, we designed the shell-thickness-controlled Ni3C@Ni/g-C3N4 photocatalysts with intimate Schottky-junctions by an in situ high-temperature transformation strategy. Meanwhile, we found that the cocatalysts with optimized Ni shell-layer thickness of 15 nm could achieve the best visible-light photocatalytic H2-production performance of 11.28 μmolh−1, with an apparent quantum yield (AQY) of 1.49 % at 420 nm, which was 16 times higher than that of Ni3C/g-C3N4. Moreover, an excellent stability is achieved. The well-defined density functional theory (DFT) calculations indicate that the “TOP_C1” sites of Ni3C@Ni can exhibit the H adsorption and Gibbs free energies of -0.07eV and 0.18 eV, respectively, which should be hydrogen-evolution active sites instead of two “HOLLOW” sites. Interestingly, the intimate Schottky-junctions, could hinder rapid charge recombination, increase reactive sites, boost catalytic kinetics and passivate unstable surface of Ni3C, thus achieving shell-thickness-dependent hydrogen evolution. Therefore, the Ni3C@Ni core–shell cocatalysts will open a new avenue for robust solar fuel production.
KW - Adsorption energy
KW - Charge separation kinetics
KW - g-CN nanosheets
KW - Photocatalytic hydrogen evolution
KW - Shell-thickness-controlled NiC@Ni core–shell co-catalyst
UR - http://www.scopus.com/inward/record.url?scp=85102356257&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2021.120104
DO - 10.1016/j.apcatb.2021.120104
M3 - Article
AN - SCOPUS:85102356257
SN - 0926-3373
VL - 291
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
M1 - 120104
ER -