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1 advances.sciencemag.org/cgi/content/full/3/8/e /dc1 This PDF file includes: Supplementary Materials for Oriented assembly of anisotropic nanoparticles into frame-like superstructures Jianwei Nai, Bu Yuan Guan, Le Yu, Xiong Wen (David) Lou Published 23 August 2017, Sci. Adv. 3, e (2017) DOI: /sciadv fig. S1. Characterization of the KCoFe-1 NAFSs. fig. S2. Overview FESEM image of the KCoFe-1 NAFSs. fig. S3. FESEM images of two NAFSs. fig. S4. Characterization of the KCoFe-2 NCs. fig. S5. XRD patterns of different samples. fig. S6. FESEM image of the product obtained at 9 hours of the reaction process. fig. S7. TEM and EDX mapping images of a typical core@satellite superstructure. fig. S8. FTIR spectra of different samples. fig. S9. TEM and HRTEM images of a typical core@satellite superstructure. fig. S10. Model of the cuboctahedral frame-like superstructure. fig. S11. Characterization of the NAFSs with different sizes. fig. S12. Overview FESEM image of the KCoFe-3 NFs. fig. S13. Characterization of the KCoFe-3 NFs. fig. S14. FESEM images of the samples obtained from different stages of the growth of NFs. fig. S15. XRD patterns of the samples derived from KCoFe-1 NAFSs and KCoFe- 3 NFs. fig. S16. Overview FESEM images of the Co-Fe oxide composites. fig. S17. Estimation of the ECSA of the catalysts. fig. S18. Reference electrode calibration in 1.0 M KOH solution. table S1. Observations from the FESEM images for different samples. table S2. FTIR peak positions of the samples of KCoFe-1, KCoFe-2, and KCoFe- 3 and their assignment.

2 table S3. Some typical examples of the relationship of the type of attachment facets, attachment angle, normal vector geometry, the number of attachment facet of a certain NP, and possible attachment motif (symmetry) in a cubic system. table S4. Comparison of Co-Fe mixed oxide NAFSs and NFs prepared in this work with some recently reported transition metal oxide based catalysts. References (65 74)

fig. S1. Characterization of the KCoFe-1 NAFSs. (A) XRD pattern. XRD result shows a typical pattern of the face-centered cubic structure of Prussian blue analogues (a = 9.82 Å).

3 fig. S1. Characterization of the KCoFe-1 NAFSs. (A) XRD pattern. XRD result shows a typical pattern of the face-centered cubic structure of Prussian blue analogues (a = 9.82 Å). Lattice parameter was roughly calculated by the Bragg s law. Splits observed in some diffraction peaks should be originated from local lattice distortion (65), which is induced by the accommodation of the hydroxylated potassium species as described in the part of the formation process and mechanism of the NAFSs in the main text. (B) EDX spectrum. EDX result indicates the atomic ratio of K: Co: Fe is 0.67: 1: fig. S2. Overview FESEM image of the KCoFe-1 NAFSs. Inset is a digital photo that shows a blue color of the sample dispersed in ethanol.

4 fig. S3. FESEM images of two NAFSs. These images show details of the assembly of nanocuboids.

fig. S4. Characterization of the KCoFe-2 NCs. (A) FESEM image. Inset is a digital photo that shows a red color of the sample dispersed in ethanol. (B) XRD pattern.

5 fig. S4. Characterization of the KCoFe-2 NCs. (A) FESEM image. Inset is a digital photo that shows a red color of the sample dispersed in ethanol. (B) XRD pattern. XRD result shows a typical pattern of the face-centered cubic structure of Prussian blue analogues (a = Å). Lattice parameter was approximately calculated by the Bragg s law. (C) TEM image. Inset is a SAED pattern, showing that the NC is dominated by {100} facets. (D) EDX spectrum. EDX result indicates the atomic ratio of K: Co: Fe is 0.07: 1: 0.67.

6 fig. S5. XRD patterns of different samples. The samples are obtained at 5 s, 2 h, 6 h, 9 h, 18 h, and 36 h of the reaction process, indicating a complete phase transition from KCoFe-2 to KCoFe-1 phase. fig. S6. FESEM image of the product obtained at 9 hours of the reaction process. This image shows the site-selected assembly of the nanocuboids (NCBs) on the edges of the NCs cores.

7 fig. S7. TEM and EDX mapping images of a typical core@satellite superstructure. These images reveal that the K element mainly distributes on the satellite structure, while Co and Fe elements distribute on both the core and satellite structures.

8 fig. S8. FTIR spectra of different samples. (A) KCoFe-2 NCs. (B) KCoFe-1 NAFSs.

fig. S9. TEM and HRTEM images of a typical core@satellite superstructure. (A) TEM image. Red and blue dashed lines delineate a typical side face and a corner of the core and the NCB, respectively.

9 fig. S9. TEM and HRTEM images of a typical core@satellite superstructure. (A) TEM image. Red and blue dashed lines delineate a typical side face and a corner of the core and the NCB, respectively. The arrows show two types of morphological alignment (face-to-face and corner-to-corner) between the core and the NCBs. Inset is the corresponding SAED pattern of the entire core@satallite superstructure. Red and blue squares are shown to represent the spots from the core and the NCBs as the satellites, respectively, though they are hardly distinguished from each other due to their close a values (10.10 Å versus 9.82 Å) in fcc structure. (B) HRTEM image of the area in the dashed rectangle in (A). The region in square shows continuous lattice fringes of {200} planes (interplanar spacing of 4.9 Å) across the region around the attachment interface of the adjacent NCBs. The arrow points to the inconspicuous attachment interface. Inset is the related FFT pattern.

10 fig. S10. Model of the cuboctahedral frame-like superstructure. This superstructure can be acquired from the oriented attachment of {110} facets of the NCs, within which three types of attachment motifs are present.

11 fig. S11. Characterization of the NAFSs with different sizes. (A) FESEM image, and (B) TEM image of the NAFSs with an average size of ca. 600 nm for the overall dimension and nm for the side length of the NCBs. Inset of (A): a magnified FESEM image displays a single NAFS. Inset of (B): the related SAED pattern shows a single-crystal-like feature. (C) FESEM image, and (D) TEM image of the NAFSs with an average size of ca. 200 nm for the overall dimension and nm for the side length of the NCBs. Inset of (C): a magnified FESEM image displays a single NAFS. Inset of (D): the related SAED pattern shows a single-crystal-like feature.

fig. S12. Overview FESEM image of the KCoFe-3 NFs. Inset is a digital photo that shows a violet color of the sample dispersed in ethanol. fig. S13. Characterization of the KCoFe-3 NFs.

12 fig. S12. Overview FESEM image of the KCoFe-3 NFs. Inset is a digital photo that shows a violet color of the sample dispersed in ethanol. fig. S13. Characterization of the KCoFe-3 NFs. (A) XRD pattern. XRD result shows a typical pattern of the face-centered cubic structure of Prussian blue analogues (a = Å). Lattice parameter was approximately calculated by the Bragg s law. (B) EDX spectrum. EDX result indicates the atomic ratio of K: Co: Fe is 0.97: 1: (C) FTIR spectrum.

fig. S14. FESEM images of the samples obtained from different stages of the growth of NFs. Representative samples are obtained at 15 min, 30 min, 45 min, 1.

13 fig. S14. FESEM images of the samples obtained from different stages of the growth of NFs. Representative samples are obtained at 15 min, 30 min, 45 min, 1.5 h, 3 h, and 6 h of the reaction process. The post-crystallization of the NCBs into intact edges of the frame-like structures can be observed after 30 min of the process.

14 fig. S15. XRD patterns of the samples derived from KCoFe-1 NAFSs and KCoFe-3 NFs. XRD results reveal that both of the samples are Co-Fe oxide composites composed of Co3O4, CoFe2O4 and K2CoO3. fig. S16. Overview FESEM images of the Co-Fe oxide composites. (A) NAFSs. (B) NFs.

15 fig. S17. Estimation of the ECSA of the catalysts. (A) Cyclic voltammetry (CV) curves at different scan rates, and (B) Current density ( J = Ja - Jc, Ja represents the anodic current density; Jc represents the cathodic current density. Ja and Jc are taken at the potential of 1.24 V) as a function of scan rate derived from (A) for the Co-Fe oxide NAFSs. (C) CV curves at different scan rates and (D) Current density ( J) as a function of scan rate derived from (C) for the Co-Fe oxide NFs. Discussion: Scan-rate dependence of CVs was performed in the potential range of V without redox processes, to obtain the capacitive current associated with double-layer charging for the Co-Fe oxide NAFSs and NFs. The electrochemical double-layer capacitance (Cdl) is determined by plotting the ΔJ = Ja - Jc at 1.24V vs. RHE against the scan rate (the linear slope is twice of the double layer capacitance Cdl) (66). The ECSA is generally proportional to the Cdl of the catalysts (66). As observed in the above figure, the linear slope for the Co-Fe oxide NAFSs is larger than that for the Co-Fe oxide NFs, suggesting a larger ECSA for the former.

16 fig. S18. Reference electrode calibration in 1.0 M KOH solution. E(RHE) = E (Ag/AgCl) V.

table S1. Observations from the FESEM images for different samples.

irregular 0 g 1 s small 70 nm nanoparticles nanocubes 0.

17 table S1. Observations from the FESEM images for different samples. FESEM image a amount of TCD b precipitation time morphology average size irregular 0 g 1 s small 70 nm nanoparticles nanocubes g (typical procedure) 5 s with truncated edges and corners 250 nm nanocubes with sharp g 15 min edges and 400 nm corners a FESEM image of the sample obtained immediately when obvious precipitation appears in the reaction solution. b TCD, trisodium citrate dehydrate.

18 table S2. FTIR peak positions of the samples of KCoFe-1, KCoFe-2, and KCoFe-3 and their assignment. Position of FTIR peaks of the samples of KFeCo-1, KFeCo-2, and KFeCo-3 and their assignment (44, 67). sample ν (CN) cm -1 Co II -N C-Fe III ν (CN) cm -1 Co II -N C-Fe II ν (CN) cm -1 Co III -N C-Fe II ν (OH) cm -1 OH - ν (H2O) cm -1 KFeCo (w) KCoFe (s) KCoFe

19 table S3. Some typical examples of the relationship of the type of attachment facets, attachment angle, normal vector geometry, the number of attachment facet of a certain NP, and possible attachment motif (symmetry) in a cubic system. type of attachment facets attachment angle normal vectors geometry number of attachment facet of a certain NP attachment motif (symmetry) 6 octahedral 5 square pyramidal 4 square planar {100} 90, 180 octahedron 3 2 trigonal pyramidal T-shaped Linear L-shaped 4 tetrahedral {111} 70.5, 109.5, 180 cube 3 trigonal pyramidal bent (V-shaped) 2 linear 4 square planar 3 trigonal planar {110} 60, 90, 120, 180 cuboctahedron linear 2 bent (V-shaped) L-shaped

20 table S4. Comparison of Co-Fe mixed oxide NAFSs and NFs prepared in this work with some recently reported transition metal oxide based catalysts. type of materials η (V) at j = 10 ma cm -2 Ref. Co-Fe mixed oxide NAFSs 0.34 Co-Fe mixed oxide NFs 0.35 this work Co3O4/Co2MnO4 nanocomposites 0.54 (68) Mn3O4/CoSe2 nanocomposites 0.45 (69) Mesoporous CuxCoyO (70) PNG-NiCo2O4 hybrid paper a 0.37 (71) Co3O4/graphene hybrid 0.31 (63) ZnxCo3-xO4 nanoarrays 0.32 (72) Ni0.75Co0.25Ox 0.35 (64) Fe incorporated mesoporous Co3O (73) Ni-Co mixed oxides nanocages 0.36 (43) NixCo3-xO4 nanowire arrays 0.37 (74) a PNG, porous nitrogen-doped graphene.

Electronic Supplementary Information

Electronic Supplementary Material (ESI) for Energy & Environmental Science. This journal is The Royal Society of Chemistry 2018 Electronic Supplementary Information Construction of hierarchical Ni-Co-P