Supplementary Information

Single Step and Template-free Synthesis of Dandelion Flower-like Core-Shell Architectures

of Metal Oxide Microspheres: Influence of Sulfidation on Particle Morphology &

Hydrodesulfurization Performance

Ramesh Kumar Chowdari*, J. Noé Díaz de León, Sergio Fuentes-Moyado

Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología, Km.

107 Carretera Tijuana-Ensenada, Ensenada, Baja California, México -22860

*Corresponding author E-mail: chowdarirameshkumar@gmail.com

Total number of Pages : 10

Total number of Figures : 11

Total number of Tables : 01

References : 06

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Figure S1. Energy dispersive X-ray spectrum of NiYMo oxide catalyst.

Figure S2. TGA-DTA analysis of NiYMo oxide catalyst.

Fig. S2 shows the TGA-DTA analysis of the NiYMo oxide, exhibited two exothermic peaks at

50 and 435 ºC with a shoulder at 520 ºC (See Fig. S2). The weight loss at 50 ºC is related to

physisorbed water, meanwhile, the peaks in the range of 350 ºC to 550 ºC are due to the release

of ammonia and water. These observations coincide with results reported for NiZnMo and

NiCuMo catalysts [1, 2].

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Figure S3. TEM-EDS maps of the NiYMo oxide catalyst (a) Electron image, (b) Ni Kα1, (C) Y Lα1, (d) Mo Lα1, (e) P Kα1, and (f) O Kα1.

Figure S4. TEM-EDS line scan of NiYMo oxide catalyst (a) Electron image, (b) Ni Kα1, (C) Y Lα1, (d) Mo Lα1, (e) P Kα1, and (f) O Kα1, and (g) relative intensities of elements.

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Figure S5. TEM image of the NiYMoS400 (a) Dandelion core-shell microspheres, (b) high magnification image of the Dandelion particles, (c) Crystalline fringes of MoS2, and (d) SAED pattern.

Figure S6. X-ray photoelectron spectrum survey analysis for NiYMo oxide catalyst.

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Figure S7. X-ray photoelectron spectra and decomposition of (a) Ni 2p and (b) Mo 3d emission line regions of NiYMo oxide catalyst.

Figure S8. X-ray photoelectron spectra of (a) Ni 2p3/2, (b) Mo 3d, and (c) S 2p of NiYMoS400 catalyst.

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Figure S9. Time courses of the hydrodesulfurization of dibenzothiophene over 20% NiMo/Al2O3

catalyst.

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Figure S10. SEM image of used catalysts NiYMoS350 (a-c), NiYMoS400 (d-f) and (g) 3d image of the surface morphology of the NiYMoS350 catalyst.

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Figure S11. TEM image of used catalysts NiYMoS350 (a-c) and NiYMoS400 (d-f). (a, d) Dandelion hollow microspheres, (b, e) Crystalline fringes of MoS2 (inset IFFT images), (c, f) SAED patterns.

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Table S1. FT-IR ATR spectra band position assignments and wavenumbers for HMTA, AHM, NiYMo oxide samples.

Sample Band position (ν cm-1) Assignment Ref.HMTA 2955, medium νas(CH2) [3]HMTA 2918, medium ν(CH2) [3]HMTA 2870, medium νs(CH2) [3]HMTA 1368, weak bending (CH2) [3]HMTA 1233, strong ν(CN) [3]HMTA 998, strong ν(CN) [3]HMTA 808, very weak rocking (CH2) [3]AHM 3474, broad ν(-OH) [4]AHM 3174, 3000, 2806 broad ν(NH) [4]AHM 1624, strong Bending(N-H) or ν(Mo═O) [4]AHM 912, weak ν(Mo═Ot) [4]AHM 830, strong Doubly coordinated oxygen stretching

ν(Mo2-O)[4]

AHM 566, weak Triply coordinated oxygen stretching ν(Mo3-O)

[4]

AHM 1394, weak Bending Mo-OH [5]AHM 870, strong ν(Mo-O-Mo) [5]AHM 618, strong ν(Mo-O) [5]NiYMo 1073, strong P-O [1]NiYMo 3413 ν(-OH) [4]NiYMo 1624, strong ν(N-H) [4]NiYMo 1394, weak Bending Mo-OH [5]NiYMo 870, strong ν(Mo-O-Mo) [5]NiYMo 692, strong ν(Y-O-W) [5]NiYMo 626, weak ν(Mo-O) [5]NiYMo 930, weak ν(Mo=O) in MoO4

2- [6]

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