Preparación para la instalación con LATCH

ODAN: 1,5-diaminonaphthalene (500 mg, 3.16 mmol) and (NH4)2S2O8 (500 mg, 2.19

mmol, 98% Alfa Aesar) were dispersed in EtOH (50 mL, absolute VWR). The dispersion was stirred for 24 h at room temperature to obtain oligomers of 1,5-diaminonaphtalene. Then the mixture was heated to 80°C in order to completely evaporate the solvent and drive the polymerization of the oligomers. When dry the resulting grey powder was heated in the tube furnace to 1000 °C at a heating rate of 20 °C min-1 and held there for 2 h. An alumina boat was used as crucible. The resulting black powder was refluxed for 8 h in 0.5 M H2SO4 to remove any metal impurities. After filtering and drying in the oven at

Fe-ODAN-14%: 1,5-diaminonaphtalene (350 mg, 2.20 mmol, 98% Alfa Aesar) and FeCl2

(114 mg, 0.900 mmol, anhydrous Sigma-Aldrich) were dispersed in EtOH (50 mL, absolute VWR). The dispersion was stirred for 24 h at room temperature to obtain oligomers of 1,5-diaminonaphtalene. Then the mixture was heated to 80 °C in order to completely evaporate the solvent and drive the polymerization of the oligomers. When dry the resulting dark violet residue was heated in the tube furnace to 1000 °C at a heating rate of 20°C min-1 and held there for 2 h while supplying a constant stream of inert nitrogen gas (BOC N6.0 grade). An alumina boat was used as crucible. The resulting black powder was refluxed for 8 h in 0.5 M H2SO4 to remove residual metal. After filtering and drying

in the oven at 60 °C overnight, the catalyst Fe-ODAN-14% (192 mg) was ready to use.

Co-ODAN-16%: The catalyst was synthesised in the same way as Fe-ODAN-14%,

with the difference that FeCl2 was replaced with CoCl2· 4 H2O (214 mg, 0.900 mmol, 99

% Sigma-Aldrich) to obtain Co-ODAN-16% (113 mg).

Fe-ODAN-1%: In a 250 mL round bottom flask, 1,5-diaminonaphtalene (1 g, 6.32

mmol, 98% Alfa Aesar) was dissolved in Ethanol (220 mL, absolute VWR). A solution of FeCl2· 4 H2O (35.6 mg, 0.200 mmol, 98 % Sigma-Aldrich) dissolved in ethanol (20 mL,

absolute VWR) was added to the solution. After 10 Minutes NH4S2O8 (1g, 4.38 mmol,

99.9 % Sigma-Aldrich) dissolved in H2O (10 mL, MilliQ 18.2 MΩ cm) was also added.

The mixture was stirred for 22h. The solvent was removed under reduced pressure and the remaining black powder was subjected to heat treatment in a tube furnace to 950°C at a heating rate of 20 °C min-1and held there for 2h while supplying a constant stream of inert nitrogen gas (BOC N6.0 grade). A quartz boat was used as crucible. The boat was thoroughly cleaned in aqua regia before use, in order to avoid cross contamination with transition metals. The resulting black powder was refluxed for 8 h in 0.5 M H2SO4

to remove residual metal. After filtering and drying in the oven at 60 °C overnight, the catalyst Fe-ODAN-1% (660 mg) was ready to use.

Fe-N/C: The catalyst Fe-ODAN-1% was heat treated for a second time in the tube

furnace with a heating rate of 20 °C min-1 held at 900°C for 2 h. After cooling down the catalyst Fe-N/C was ready to use.

Co-N/C: The catalyst was synthesised in the same was as Fe-N/C, with the differ-

ence that FeCl2· 4 H2O was replaced with CoCl2· 6 H2O (40 mg, 0.17 mmol, 98% Sigma-

Rh-N/C:The catalyst was synthesised in the same was as Fe-N/C, with the difference that FeCl2· 4 H2O was replaced with RhCl3· xH2O (26 mg, 99.8% Sigma-Aldrich 40 %

Rh) to obtain the Rh-N/C catalyst (634 mg).

Ru-N/C: The catalyst was synthesised in the same was as Fe-N/C, with the differ-

ence that FeCl2· 4 H2O was replaced with RuCl3· xH2O (23.5 mg, ReagentPlus® Sigma-

Aldrich 38% Ru) to obtain the Ru-N/C catalyst (687 mg).

Mn-N/C:The catalyst was synthesised in the same was as Fe-N/C, with the difference

that FeCl2· 4 H2O was replaced with MnCl2 (23.0 mg, 0.18 mmol, purum anhydrous

Sigma-Aldrich) to obtain the Mn-N/C catalyst (634 mg).

Ni-N/C: The catalyst was synthesised in the same was as Fe-N/C, with the difference

that ceNiCl2*6H2O (40.4 mg, 0.17 mmol, ReagentPlus® Sigma-Aldrich) to obtain the

Ni-N/Ccatalyst (678 mg).

Cr-N/C: The catalyst was synthesised in the same was as Fe-N/C, with the difference

that ceCrCl3*6H2O (51.25 mg, 0.17 mmol, ReagentPlus® Sigma-Aldrich) to obtain the

Cr-N/C catalyst (678 mg).

Ir-N/C: The catalyst was synthesised in the same was as Fe-N/C, with the difference

that IrCl3· xH2O (23 mg, ReagentPlus® Sigma-Aldrich) to obtain the Ir-N/C catalyst

(634 mg).

N/C: This catalyst was synthesised in the same way as Fe-N/C, with the difference that no metal salt was added to the reaction mixture. Additionally, in order to minimise trace metal contamination, the 1,5-diaminonaphthalene (98% Alfa Aesar) was recrystal- lized from ethanol (absolute, VWR) twice before use. Futhermore, the NH4S2O8 (BioX-

tra, >98.0% Sigma-Aldrich) utilised contained less than 5 ppm trace metal impurities. Moreover, all glassware was meticulously cleaned with aqua regia, a 1:1 solution of 2 M H2SO4/30 wt% H2O2 and ultrapure water (MilliQ 18.2 MΩ cm) before use.

MgO APS 1: In a 250 mL round bottom flask, MgO nanoparticles (1g, <60 nm Sigma-

Aldrich) were dispersed in ethanol (250 mL, absolute VWR) and 1,5-diaminonapthalene (1g, 6.3 mmol, 98% Alpha Aeser) was added. The mixture was stirred for 15 minutes in order to completely dissolve the diamine. FeCl2· 4 H2O (40 mg, 0.17 mmol, 98% Sigma-

Aldrich) was dissolved in ethanol (20 mL, absolute VWR). The solution was added to the diamine solution. It was stirred for 15 minutes in order to ensure a homogeneous dispersion

of the catalyst. 1g (4.3 mmol) of (NH4)2S2O8(98% Sigma-Aldrich) was dissolved in 10 mL

H2O (MilliQ 18.2 MΩcm) and added to the ethanolic solution. The mixture was stirred

for 22h to allow polymerisation. The solvent was then removed under reduced pressure. The remaining black solid was heated at 20°C min-1 to 950°C under a constant stream of inert nitrogen (BOC N6.0 Grade) in a tube furnace (Carbolite). The temperature was held for 2 h and the reaction was cooled to room temperature overnight. The black product was then refluxed in 0.5 M H2SO4 for 8 h to remove any residual metal. After

drying in the oven at 60°C overnight, the catalyst (300 mg) was ready to use.

MgO H2O2 1: 50 mg of MgO APS 1 was heated at 20°C min-1 to 950°C under a

constant stream of inert nitrogen (BOC N6.0 grade) in a tube furnace (Carbolite). The temperature was held for 2 h and the reaction was cooled to room temperature overnight. The product 47 mg was ready to use.

MgO H2O2 2: 50 mg of MgO H2O2 1 was heated at 20 °C min-1 to 950 °C under a

constant stream of inert nitrogen (BOC N6.0 grade) in a tube furnace (Carbolite). The temperature was held for 2 h and the reaction was cooled to room temperature overnight. The product (42 mg) was ready to use.

MgO H2O2 2 HCl: Was synthesised in the same way as MgO H2O2 2, but 0.5 M

HCl was used for the acid leaching step instead of 0.5 M H2SO4