Supporting Information. Fabricating carbon catalysts via a thermal. method

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1 Supporting Information Fabricating carbon catalysts via a thermal method Yueling Cao,, Bowen Zhao, Xiaobing Bao, Yong Wang* Advanced Materials and Catalysis Group, Institute of Catalysis, Zhejiang University, Hangzhou , People s Republic of China Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi'an , People s Republic of China *Corresponding author at: Advanced Materials and Catalysis Group, Institute of Catalysis, Zhejiang University, Hangzhou , P. R. China. address: chemwy@zju.edu.cn. Experimental section Materials RuCl 3 xh 2 O (Ru= %), (NH 4 ) 3 RhCl 6 (Rh=27.5%), H 2 PtCl 6 6H 2 O (Pt=37.5%), Chitin, levulinic acid (AR, 99%), γ-valerolactone (AR, 98%), -chlorobenzoic acid (AR), 4-bromobenzoic acid (AR, 98%), 4-hydroxybenzoic acid (AR, 99%), and 3-phenylpropionic acid (AR, 99%) were used as received from Aladdin Chemistry Co., Ltd. Benzoic acid (AR, >99.5%), Furfural (AR, 99.0%), Phenol (AR, 99.0%), NaBH 4 (AR, >96%) were purchased from Sinopharm

2 Chemical Reagent Co., Ltd. Phenyl acetic acid (AR) was purchased from Shanghai Lingfeng Chemical Reagent Co., Ltd. Activated carbon (AC) was purchased from Jiangsu Liangyou Environmental protection technology Co., Ltd. Catalyst synthesis The synthesis of composites involved one-pot pyrolysis of chitin and RuCl 3 xh 2 O. In a typical experiment, chitin (2.0 g) and 2 ml of an aqueous solution of RuCl 3 xh 2 O (10 mg/ml) were added into ethanol solution, and then the as-made solution was heated by oil bath at 60 C until completely drying to form a powder. Subsequently, the dried powder was transformed into a furnace and heated at suitable temperature ( C) for 2.0 h (with a heating rate of 5 C/min) under nitrogen flow of 400 ml/min. The obtained catalysts were denoted as Ru@CN-x, where x stands for the pyrolysis temperature. For the Ru-based bimetallic catalysts, aqueous solutions containing RuCl 3 xh 2 O and (NH 4 ) 3 RhCl 6 or RuCl 3 xh 2 O and H 2 PtCl 6 6H 2 O, respectively, were utilized. For comparison, two kinds of catalysts were prepared using commercial AC and chitin-derived carbon (CN: prepared by the pyrolysis of chitin at 800 C for 2.0 h) as the support. Ru/AC-IM and Ru/CN-IM catalysts were prepared via conventional impregnation method. Catalyst post-synthesis treatment Heat treatment: The obtained Ru@CN-x was reduced in flow hydrogen at 150, 250, 350, and 450 o C for 2 h, denoted as Ru@CN-x-yH, where y and H stand for the reduction temperature and hydrogen atmosphere, respectively. Other post-synthesis treatment is the as-prepared catalyst treated with both air and hydrogen. Typically, the

3 obtained was calcined in static air at various temperatures for 3 h first and then reduced in flow hydrogen at 350 o C for 2 h, denoted as Ru@CN-x-zA-350H, where z and A stand for the calcination temperature and air atmosphere, respectively; 350H stands for the reduction temperature in hydrogen atmosphere. Characterizations The structure of the as-obtained catalysts was characterized by X-ray diffraction (XRD, Ultima TV, Cu Kα irradiation, operated at 40 kv and 30 ma). The actual loading of Ru in various catalysts was measured using inductively coupled plasma-atomic emission spectroscopy (ICP-AES, Plasma-Spec-ΙΙ spectrometers). Then the BET surface area was tested on an ASAP 2020 HD88 instrument, BET equation was used to calculate the surface area and pore volume. Raman spectra were also collected on a Raman spectrometer (JY, HR 800) using nm argon laser. Thermogravimetric-mass spectrometry (TG-MS) experiments were carried out using METTLER TOLEDO TGA/DSC 1100SF and ThermoStar gas mass spectrometry. The size and dispersity of Ru particles in the samples were measured using transmission electron microscopy (TEM) with a JEM-2000 and averaged over 150 monodispersed Ru particles. Hydrogen temperature-programmed reduction coupled with mass spectrometry (H 2 -TPR-MS) experiments were performed using a self-made TPD/TPR instrument and an on-line Hiden gas analyzer (QIC 20). The pulse CO chemisorption experiments on various Ru-based catalysts were conducted using an Auto Chem 2920 instrument equipped with a thermal conductivity detector (TCD). Assuming CO:Ru stoichiometry of 1:1, the CO uptake and metal area were calculated using following equations: (1)

4 (2) where n CO is the mol amount of adsorbed CO, m cat. is the weight of catalyst used in the experiment, S metal is the cross-sectional area of Ru ( nm 2 ), R is Avogadro's constant ( mol -1 ). The X-ray photoelectron spectra (XPS) were obtained by an ESCALAB MARK II spherical analyzer using an aluminum magnesium binode (Al ev; Mg, ev) X-ray source. Catalytic tests The electrochemical tests were carried out in a conventional three electrode electrochemical cell by using a CHI750E. A commercial glassy carbon electrode (GCE, 5 mm diameter, cm 2 ) was served as the working electrode. The presented current density referred to the geometric surface area of the GCE. A saturated calomel electrode (SCE) and Pt plate were used as the reference electrode and the counter electrode, respectively. The preparation of the working electrode was performed as described below: ethanol suspensions containing 500 μl ethanol, 3 mg of catalyst, and 50 μl 5 wt % Nafion solutions were obtained by ultrasonic mixing for about 30 min. The 10 μl of the catalyst ink suspension thus obtained was coated onto the polished GC electrode, and then it was left to dry in air. Electrochemical measurements of catalysts were measured after purging the electrolyte with N 2 gas for 30 min at 25 o C. The hydrogenation reaction was carried out in a 50 ml stainless-steel autoclave. In a typical procedure, levulinic acid (500 mg), catalyst (20 mg) and deionized water (5 ml) were introduced into the stainless-steel autoclave, and then the reactor was purged with H 2 to remove air. Subsequently, the reactor was filled with 2.0 MPa

5 hydrogenation pressure at room temperature and finally heated to a desired temperature with a stirring speed of 1000 rpm. After the reaction, the contents of products and substrate were determined by GC-FID and the products were identified by GC-MS. In order to examine stability of the catalysts, they were recycled in repeated runs. First, levulinic acid (1000 mg), deionized water (5 ml) and an excess of Ru@CN (200 mg) were added into the batch reaction and the catalytic hydrogenation was carried out at 100 o C and 2 MPa H 2 for 0.5 h. After the first run, the recovered catalyst was washed with deionized water and dried overnight at 40 o C under vacuum, and then 20 mg of catalyst was taken from them and was used for the next run (This is second cycle). Meanwhile, the remanent Ru@CN catalyst was tested under same reaction conditions: Ru@CN, levulinic acid (1000 mg), deionized water (5 ml) at 100 C and 2 MPa H 2 for 0.5 h. Afterwards, the recovered catalyst was washed with deionized water and dried overnight at 40 o C under vacuum, and then 20 mg of catalyst was taken from them and was used for the next run (This is third cycle). Subsequent re-usability tests were carried out on the same material by following the same procedure.

6 Figure S1. TEM images and particle size distribution of various catalysts pyrolyzed at different temperatures: (A and B) (C and D) (E and F) (G and H) (I and J)

7 Figure S2. XRD patterns of various catalysts pyrolyzed at different temperatures. No peaks belonging to ruthenium was observed in all samples except for indicating that Ru species on the catalysts might be well dispersed, which is in line with the TEM results (as shown in Figure. S1). Moreover, one weak peak at 44.0 was observed in which corresponded to the characteristic diffractions of metallic Ru (JCPDS ), indicating the sintering of Ru NPs under high pyrolysis temperature. However, it should be noted that there are many other peaks appeared in all XRD patterns, which resulted from the impurity of chitin such as CaCO 3. It is well known that chitin extracted from crustacean shells normally contain various minerals, mainly calcium carbonate. 1-2

8 Figure S3. Ru 3p (A) and N 1s (B) XPS spectra of various Ru@CN catalysts pyrolyzed at different temperatures. Figure S4. Raman spectrum of Ru@CN-800 catalyst.

9 Figure S5. XRD patterns of catalyst before and after heat treatment. Figure S6. Ru 3p (A) and N 1s (B) XPS spectra of Ru@CN-800 catalyst before and after heat treatment.

10 Figure S7. Bright-field and dark-field TEM images of catalyst (A and B) and catalyst (C and D).

11 Figure S8. TEM images and particle size distribution of catalyst (fresh: A and B, spent: C and D) and Ru/AC-IM catalyst (fresh: E and F, spent: G and H).

12 Figure S9. Transmission electron microscope and EDS mapping and/or line scan of various Ru-based catalysts (A-E) and (F and G)

13 Figure S10. Effect of hydrogen pressure on the catalytic activity of catalyst. Reaction conditions: catalyst 20 mg, LA 0.50 g, H 2 O 5 ml, 60 o C, 60 min.

14 Table S1. Effect of pyrolysis temperature on the catalytic activity of as-prepared catalysts. Catalyst Conversion (%) Selectivity (%) Reaction conditions: catalyst 20 mg, LA 0.50 g, H 2 O 5 ml, 100 o C, 2.0 MPa H 2, 60 min. Table S2. Ru content in different catalysts. Catalyst Fresh Ru content a Ru loss (%) Used Ru@CN A-350H Rh/AC-IM a Calculated by ICP-AES.

15 Table S3. Effect of heat treatment on the catalytic activity of and catalysts. Catalyst Calcination Temperature ( o C) Reduction Time (min) Conversion (%) Selectivity (%) Ru@CN-700 no no Ru@CN-700 no Yes Ru@CN Yes Ru@CN-750 no no Ru@CN-750 no Yes Ru@CN Yes Reaction conditions: catalyst 20 mg, LA 0.50 g, H 2 O 5 ml, 100 o C, 2.0 MPa H 2.

16 Table S4. Effect of reaction temperature on the catalytic activity of catalyst. Temperature ( o C) Time (min) Conversion (%) Selectivity (%) Reaction conditions: Ru@CN A-350H 20 mg, LA 0.50 g, H 2 O 5 ml, 100 o C, 2.0 MPa H 2.

17 References 1. Paul, B.; Jaime, L. M.; Michael, H. Comparison of chitins produced by chemical and bioprocessing methods. J. Chem. Technol. Biot. 2005, 80, Rødde, R. H.; Einbu, A.; Vårum, K. M. A seasonal study of the chemical composition and chitin quality of shrimp shells obtained from northern shrimp (Pandalus borealis). Carbohyd. Polym. 2008, 71,