Supplementary Materials for

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1 advances.sciencemag.org/cgi/content/full/3/6/e1758/dc1 Supplementary Materials for A selective electrocatalyst ased direct methanol fuel cell operated at high concentrations of methanol This PDF file includes: Yan Feng, Hui Liu, Jun Yang Pulished 3 June 217, Sci. Adv. 3, e1758 (217) DOI: /sciadv.1758 fig. S1. Core-shell-shell Au@Ag2S@Pt nanocomposites and core-shell Au@Pd nanoparticles supported on caron sustrates. fig. S2. Electrochemical measurements of core-shell-shell Au@Ag2S@Pt nanocomposites. fig. S3. Electrochemical measurements of core-shell Au@Pd nanoparticles. fig. S4. A prototype of the memraneless DMFC. fig. S5. Open circuit voltage. fig. S6. Transient voltages. fig. S7. DMFC stack with 15 selective catalyst ased MEAs connected in series. tale S1. Comparison etween this study and literatures in the recent 5 years on DMFCs, with emphasis on the high-concentration solutions of methanol.

2 a 5 nm 2 nm c d 2 nm 2 nm fig. S1. Core-shell-shell Au@Ag 2S@Pt nanocomposites and core-shell Au@Pd nanoparticles supported on caron sustrates. TEM images (a, c) and HRTEM images (, d) of core-shell-shell Au@Ag 2S@Pt nanocomposites (a, ) and core-shell Au@Pd nanoparticles (c, d) supported on caron sustrates. Inlets are the photos of the corresponding products.

3 a I (ma) c Au@Ag 2 S@Pt j (ma cm -2 ) d Au@Ag 2 S@Pt j (ma cm -2 ) Au@Ag 2 S@Pt I (ma) Au@Ag 2 S@Pt t (s) fig. S2. Electrochemical measurements of core-shell-shell Au@Ag 2S@Pt nanocomposites. Cyclic voltammograms of Au@Ag 2S@Pt nanocomposites and commercial catalysts in argon-purged HClO 4 electrolyte (.1 M) at a scan rate of 5 mv s -1 (a); cyclic voltammograms of Au@Ag 2S@Pt nanocomposites and commercial in argon-purged HClO 4 (.1 M) with methanol of 1 M at a scan rate of 2 mvs -1 (); ORR polarization curves for the Au@Ag 2S@Pt nanocomposites and commercial catalysts, recorded at room temperature in an O 2-saturated HClO 4 solution (.1 M) at a scan rate of 2 mvs -1 and a rotating speed of 16 rpm (c); and chronoamperograms of Au@Ag 2S@Pt nanocomposites and commercial catalysts at.45 V vs Ag/AgCl in argon-purged HClO 4 (.1 M) with 1 M methanol (d).

4 a I (ma) c j (ma cm -2 ) Pd/C Au@Pd Au@Pd j (ma cm -2 ) d I (ma) Pd/C Au@Pd Pd/C Au@Pd t (s) fig. S3. Electrochemical measurements of core-shell Au@Pd nanoparticles. Cyclic voltammograms for CO stripping on core-shell Au@Pd nanoparticles and commercial Pd/C catalyst in.1 M HClO 4 at a scan rate of 5 mv s -1 (a); ORR polarization curves for the core-shell Au@Pd nanoparticles, commercial Pd/C, and commercial catalysts, recorded at room temperature in an O 2-saturated HClO 4 solution (.1 M) at a scan rate of 2 mvs -1 and a rotating speed of 16 rpm (); cyclic voltammograms of core-shell Au@Pd nanoparticles and commercial catalysts in argon-purged HClO 4 (.1 M) with methanol of 1 M at a scan rate of 2 mvs -1 (c); and chronoamperograms of core-shell Au@Pd nanoparticles, commercial Pd/C, and commercial catalysts at.55 V vs Ag/AgCl in an O 2 saturated.1 M HClO 4 electrolyte at a scan rate of 2 mv s -1 and a rotating rate of 16 rpm (d).

5 a O 2 O 2 Electrolyte.6 Au@Ag 2 S@Pt (Anode) Au@Pd (Cathode).5.4 Au@Ag2S@Pt vs. Au@Pd without memrane Voltage (V) Au@Ag2S@Pt vs. Au@Pd with memrane -.1 vs. without memrane Time (s) fig. S4. A prototype of the memraneless DMFC. Schematic for the memraneless DMFC (a), The open-circuit voltage of memraneless DMFC with selective MOR and ORR electrocatalysts in comparison with that of memraneless DMFC using commercial catalysts (). Inlet in (a) is the practical photo of the memraneless DMFC.

6 a Cell voltage (V).63.5 M 1M 2M 4M 6M 8M 1 M 15 M Time (s) Cell voltage (V).63.5 M 1M 2M 4M 6M 8M 1 M 15 M Time (s) fig. S5. Open circuit voltage. The OCV of the assemled DMFC with selective ORR and MOR catalysts (a), and with commercially non-selective catalysts (). The tests were performed under methanol concentration from.5 to 15 M..5 Au@Ag2S@Pt vs Au@Pd voltage (V).4.3 vs Time (h) fig. S6. Transient voltages. Transient voltages of the assemled DMFC with selective ORR and MOR catalysts, and with commercially non-selective catalysts (fuel: 1 M methanol, operating current density: 2 ma cm-2).

7 a fig. S7. DMFC stack with 15 selective catalyst ased MEAs connected in series. Photographs for applying the DMFC stack to a 7-W experimental ul: switch off (a), switch on ().

8 tale S1. Comparison etween this study and literatures in the recent 5 years on DMFCs, with emphasis on the high-concentration solutions of methanol. Investigator Methanol Power density Technologies used Concentration (M) (mw cm -2 ) This study Selective catalysts Park et al MEA design Kang et al MEA design He et al , Heat and mass transfer Nam et al a Silica as a catalyst support Yuan, et al Structural diversity and orientation dependence Kim et al A micro-porous layer for the anode Yuan et al Mass-transfer-controlling Lin et al Memrane modification Wu, et al Pure 47 Memrane modification Yan et al Current collector Yuan et al Anodic methanol arrier Kang et al Hydrophoicity of anode diffusion media Yao, et al Memrane modification Paneri, et al Memrane modification Yuan, et al Operational and structural aspects Zhang et al Mass transfer arrier Deng et al Cathode gas diffusion electrode Nataraj, et al Memrane modification

9 Gago, et al Comprehensive characterization and understanding Li, et al Memrane modification Yan, et al Memrane modification Yuan et al Porous control medium Yuan et al Diverse flow fileds Seastián et al Catalyst Seastián et al Non-Pt metal catalyst a achieved at methanol concentration of 1 M. achieved at methanol concentration of 1 M.