TY - JOUR
T1 - Kinetically Controlled Synthesis of Pd-Cu Janus Nanocrystals with Enriched Surface Structures and Enhanced Catalytic Activities toward CO2Reduction
AU - Lyu, Zhiheng
AU - Zhu, Shangqian
AU - Xu, Lang
AU - Chen, Zitao
AU - Zhang, Yu
AU - Xie, Minghao
AU - Li, Tiehuai
AU - Zhou, Shan
AU - Liu, Jingyue
AU - Chi, Miaofang
AU - Shao, Minhua
AU - Mavrikakis, Manos
AU - Xia, Younan
N1 - Publisher Copyright:
©
PY - 2021/1/13
Y1 - 2021/1/13
N2 - Bimetallic nanocrystals often outperform their monometallic counterparts in catalysis as a result of the electronic coupling and geometric effect arising from two different metals. Here we report a facile synthesis of Pd-Cu Janus nanocrystals with controlled shapes through site-selected growth by reducing the Cu(II) precursor with glucose in the presence of hexadecylamine and Pd icosahedral seeds. Specifically, at a slow reduction rate, the Cu atoms nucleate and grow from one vertex of the icosahedral seed to form a penta-twinned Janus nanocrystal in the shape of a pentagonal bipyramid or decahedron. At a fast reduction rate, in contrast, the Cu atoms can directly nucleate from or diffuse to the edge of the icosahedral seed for the generation of a singly twinned Janus nanocrystal in the shape of a truncated bitetrahedron. The segregation of two elements and the presence of twin boundaries on the surface make the Pd-Cu Janus nanocrystals effective catalysts for the electrochemical reduction of CO2. An onset potential as low as -0.7 VRHE (RHE: reversible hydrogen electrode) was achieved for C2+ products in 0.5 M KHCO3 solution, together with a faradaic efficiency approaching 51.0% at -1.0 VRHE. Density functional theory and Pourbaix phase diagram studies demonstrated that the high CO coverage on the Pd sites (either metallic or hydride form) during electrocatalysis enabled the spillover of CO to the Cu sites toward subsequent C-C coupling, promoting the formation of C2+ species. This work offers insights for the rational fabrication of bimetallic nanocrystals featuring desired compositions, shapes, and twin structures for catalytic applications.
AB - Bimetallic nanocrystals often outperform their monometallic counterparts in catalysis as a result of the electronic coupling and geometric effect arising from two different metals. Here we report a facile synthesis of Pd-Cu Janus nanocrystals with controlled shapes through site-selected growth by reducing the Cu(II) precursor with glucose in the presence of hexadecylamine and Pd icosahedral seeds. Specifically, at a slow reduction rate, the Cu atoms nucleate and grow from one vertex of the icosahedral seed to form a penta-twinned Janus nanocrystal in the shape of a pentagonal bipyramid or decahedron. At a fast reduction rate, in contrast, the Cu atoms can directly nucleate from or diffuse to the edge of the icosahedral seed for the generation of a singly twinned Janus nanocrystal in the shape of a truncated bitetrahedron. The segregation of two elements and the presence of twin boundaries on the surface make the Pd-Cu Janus nanocrystals effective catalysts for the electrochemical reduction of CO2. An onset potential as low as -0.7 VRHE (RHE: reversible hydrogen electrode) was achieved for C2+ products in 0.5 M KHCO3 solution, together with a faradaic efficiency approaching 51.0% at -1.0 VRHE. Density functional theory and Pourbaix phase diagram studies demonstrated that the high CO coverage on the Pd sites (either metallic or hydride form) during electrocatalysis enabled the spillover of CO to the Cu sites toward subsequent C-C coupling, promoting the formation of C2+ species. This work offers insights for the rational fabrication of bimetallic nanocrystals featuring desired compositions, shapes, and twin structures for catalytic applications.
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U2 - 10.1021/jacs.0c05408
DO - 10.1021/jacs.0c05408
M3 - Article
C2 - 33370094
AN - SCOPUS:85099031195
SN - 0002-7863
VL - 143
SP - 149
EP - 162
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 1
ER -