Supporting information imetallic AuRh nanodendrites consisting of Au icosahedron cores and atomically ultrathin Rh nanoplate shells: synthesis and light-enhanced catalytic activity Yongqiang Kang 1,2, Qi Xue 1,2, Ruili Peng 1, Pujun Jin 1, Jinghui Zeng 1, Jiaxing Jiang 1, and Yu Chen 1 1 Key Laboratory of Macromolecular Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry (MOE), Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi an, P. R. China. Correspondence: Associate Professor Dr PJ Jin or Professor Dr Y Chen, Key Laboratory of Macromolecular Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry (MOE), Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an 710062, P. R. China. E-mail: jinpj@snnu.edu.cn or ndchenyu@gmail.com. 2 These authors contributed equally to this work. S1
A Scheme S1. The molecular structure of (A) polyallylamine hydrochloride and () diethylene glycol. 90 nm Frequency 64 72 80 88 96 104 112 120 128 Diameter / nm Figure S1. The particle size distribution histogram of bimetallic Au@Rh core shell nanodendrites based on SEM image in Figure1. S2
CPS 16 14 12 10 8 6 4 2 x10 3 Name At% Rh 3d 91.6 Au 4f 8.4 Rh 3d Au 4f 0 1200 1000 800 600 400 200 0 inding Energy / ev Figure S2. XPS spectrum of bimetallic Au@Rh core shell nanodendrites. A 87 nm Frequency 64 72 80 88 96 104 Diameter / nm Figure S3. (A) TEM image of bimetallic Au@Rh core shell nanodendrites and () corresponding particle size distribution histogram. Figure S4. HRTEM image of the reaction intermediates at 0.5 h. S3
A T5 T2 T3 T4 T1 T2 T3 T4 T5 T1 Figure S5. (A) TEM and () HRTEM image of the reaction intermediates at 1 h. Top inset: a schematic structure model of icosahedron. ottom inset: FFT pattern of an individual Au icosahedron. T: twin boundary. As observed, Au nanocrystals show obvious 5-fold axial twinned structures. Meanwhile, the five-fold symmetry is readily apparent in the FFT pattern, which indicates Au nanocrystals are five-fold twinning structure. Thus, HRTEM image and FFT pattern demonstrate the obtained are Au icosahedra. 1-3 A Figure S6. (A) TEM and () HRTEM images of the obtained Au nanocrystals in the absence of diethylene glycol at 1 h. S4
Figure S7. (A) TEM, () HAADF-STEM image and coressponding EDXmapping images, and (C) HRTEM image of the obtained Au-Rh nanocrystals in the absence of polyallylamine hydrochloride. A Figure S8 (A) TEM and () HRTEM images of obtained monometallic Rh nanodendrites in the absence of HAuCl4. Figure S9. TEM image of bimetallic Au@Rh core shell nanodendrites obtained by changing the molar ratio of HAuCl4/RhCl3 to 1:10. Gas volume / ml 4 303 K 313 K 323 K 3 2 1 ln TOF 1.2 0.8 0.4 0.0-0.4 0.0031 0.0032 0.0033 1/T / K -1 0 0 50 100 150 200 250 300 Time / min S5 ln TOF = -7122.5 (1/T) + 23 Ea=59.2 KJ mol -1
Figure S10. Volume of the generated gas (H2 + N2) versus time for the HGR- N2H4 at commercial Rh black at 30 C, 40 C and 50 C. Insert: Plot of lntof versus 1/T at different temperatures. Scheme S2. The illustration for (A) bulk metal nanocrystals and () the atomically thick ultrathin nanoplate. Figure S11. Volume of the generated gas (H2 + N2) versus time for HGR-N2H4 at single-component Au nanocrystals at 30 C with light irradiation. S6
Gas volume / ml 16 reactions without light 14 reactions under light 12 10 8 6 4 2 0 0 10 20 30 40 50 60 70 80 Time / min Figure S12. Volume of the generated gas (H2 + N2) versus time for HGR-N2H4 at single-component Rh nanodendrites at 30 C with and without light irradiation. Figure S13. TEM images of (A) monometallic Au nanocrystals, () monometallic Rh nanodendrites, and (C) the mixture of Au nanocrystals and Rh nanodendrites. (D) HAADF-STEM image image of the mixture of Au nanoparticles and Rh nanodendrites and coressponding EDX-mapping images. S7
Figure S14. Volume of the generated gas (H2 + N2) versus time for the HGR- N2H4 at the mixture of Au nanocrystals and Rh nanodendrites at 30 C with and without light irradiation. A Figure S15. imetallic Au@Rh core shell nanodendrites (A) before and () after the 7 cycles runs. S8
n(n 2 +H 2 ) / n(n 2 H 4 ) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 Au@Rh nanodendrites 0.0 0 10 20 30 40 50 60 Time / min Figure S16. The HGR-N2H4 reactivity and H2 selectivity versus time course plots of bimetallic Au@Rh core shell nanodendrites. The selectivity toward H2 generation (λ) was calculated to be 1.5 by using equation λ=n(h2+n2)/n(h2nnh2). 4, 5 3. Supplementary references 1. Xiong, Y.J., McLellan, J.M., Yin, Y.D. & Xia, Y.N. Synthesis of palladium icosahedra with twinned structure by blocking oxidative etching with citric acid or citrate ions. Angew. Chem. Int. Ed. 46, 790-794 (2007). 2. Fu, G., Jiang, X., Tao, L., Chen, Y., Lin, J., Zhou, Y., Tang, Y. & Lu, T. Polyallylamine functionalized palladium icosahedra: one-pot water-based synthesis and their superior electrocatalytic activity and ethanol tolerant ability in alkaline media. Langmuir 29, 4413-4420 (2013). 3. Johnson, C.L., Snoeck, E., Ezcurdia, M., Rodriguez-Gonzalez,., Pastoriza-Santos, I., Liz-Marzan, L.M. & Hytch, M.J. Effects of elastic anisotropy on strain distributions in decahedral gold nanoparticles. Nat. Mater. 7, 120-124 (2008). 4. Xia,., Chen, K., Luo, W. & Cheng, G. NiRh nanoparticles supported on nitrogen-doped porous carbon as highly efficient catalysts for dehydrogenation of hydrazine in alkaline solution. Nano Res. 8, 3472-3479 (2015). 5. Sun, J.-K. & Xu, Q. Metal nanoparticles immobilized on carbon nanodots as highly active catalysts for hydrogen generation from hydrazine in aqueous solution. ChemCatChem 7, 526-531 (2015). S9