Synthesis · Ultrafast transformation of metal-organic frameworks into advanced oxygen evolution electrocatalysts with good universality and scalability

16 structured synthesis routes

Completeness describes how fully the route could be reconstructed from the main article and supporting information.

Complete recipeSource: SI

Route 1: Other

S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11

Metal precursorsCo(NO3)2.6H2O plus Cd(NO3)2.4H2O

Linker precursors2-methylimidazole

SolventsDI water; substrate cleaned with 3 M HCl, ethanol and DI water

Atmospherenot specified

Temperatureroom temperature; dry at 60 deg C

Time4 h reaction; dried overnight

Substrate orientationNi foam substrate

Work-upCleaned with DI water and dried at 60 deg C overnight.

ActivationElectrochemical activation by CV before OER testing, not part of synthesis.

Scalability contextPrepared by the same solution method as CoNi MOFs.

Show 4 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Co(NO3)2.6H2O	40 mL solution A · 0.04 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Metal Source	Cd(NO3)2.4H2O	replacement for Ni(NO3)2.6H2O · 0.01 M inferred from same way	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Linker	2-methylimidazole	40 mL · 0.4 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Other	Ni foam	2 cm x 5 cm in parent recipe	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11

Complete recipeSource: SI

Route 2: Other

S2-S3 · Synthesis of CoNi MOFs on Ni foam

Metal precursorsCo(NO3)2.6H2O plus Cu(NO3)2.3H2O, Mn(NO3)2.4H2O, Cd(NO3)2.4H2O or Zn(NO3)2.6H2O

Linker precursors2-methylimidazole

SolventsDI water; substrate cleaned with 3 M HCl, ethanol and DI water

Atmospherenot specified

Temperatureroom temperature; dry at 60 deg C

Time4 h reaction; dried overnight

Substrate orientationNi foam substrate

Work-upCleaned with DI water and dried at 60 deg C overnight.

ActivationElectrochemical activation by CV before OER testing, not part of synthesis.

Scalability contextPrepared by the same solution method as CoNi MOFs.

Show 4 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Co(NO3)2.6H2O	40 mL solution A · 0.04 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam
Metal Source	Cu(NO3)2.3H2O / Mn(NO3)2.4H2O / Cd(NO3)2.4H2O / Zn(NO3)2.6H2O	replacement for Ni(NO3)2.6H2O · 0.01 M inferred from 'same way'	S2-S3 · Synthesis of CoNi MOFs on Ni foam
Linker	2-methylimidazole	40 mL · 0.4 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam
Other	Ni foam	2 cm x 5 cm in parent recipe	S2-S3 · Synthesis of CoNi MOFs on Ni foam

Complete recipeSource: SI

Route 3: Other

S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11

Metal precursorsCo(NO3)2.6H2O plus Mn(NO3)2.4H2O

Linker precursors2-methylimidazole

SolventsDI water; substrate cleaned with 3 M HCl, ethanol and DI water

Atmospherenot specified

Temperatureroom temperature; dry at 60 deg C

Time4 h reaction; dried overnight

Substrate orientationNi foam substrate

Work-upCleaned with DI water and dried at 60 deg C overnight.

ActivationElectrochemical activation by CV before OER testing, not part of synthesis.

Scalability contextPrepared by the same solution method as CoNi MOFs.

Show 4 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Co(NO3)2.6H2O	40 mL solution A · 0.04 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Metal Source	Mn(NO3)2.4H2O	replacement for Ni(NO3)2.6H2O · 0.01 M inferred from same way	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Linker	2-methylimidazole	40 mL · 0.4 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Other	Ni foam	2 cm x 5 cm in parent recipe	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11

Complete recipeSource: SI

Route 4: Other

S2 · Synthesis of CoNi MOFs on Ni foam

Metal precursorsCo(NO3)2.6H2O and Ni(NO3)2.6H2O

Linker precursors2-methylimidazole (C4H6N2)

SolventsDI water; substrate cleaned with 3 M HCl, ethanol and DI water

Atmospherenot specified

Temperatureroom temperature; dry at 60 deg C

Time4 h reaction; dried overnight

Substrate orientationCommercial Ni foam, 2 cm x 5 cm, immediately immersed in mixed solution

Work-upSample taken out, cleaned with DI water, and dried at 60 deg C overnight.

ActivationElectrochemical activation by CV before OER testing, not part of synthesis.

Show 6 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Co(NO3)2.6H2O	40 mL solution A · 0.04 M	S2 · Synthesis of CoNi MOFs on Ni foam
Metal Source	Ni(NO3)2.6H2O	40 mL solution A · 0.01 M	S2 · Synthesis of CoNi MOFs on Ni foam
Linker	2-methylimidazole (C4H6N2)	40 mL solution B · 0.4 M	S2 · Synthesis of CoNi MOFs on Ni foam
Solvent	DI water	Not specified	S2 · Synthesis of CoNi MOFs on Ni foam
Acid	HCl	substrate cleaning · 3 M	S2 · Synthesis of CoNi MOFs on Ni foam
Other	Ni foam	2 cm x 5 cm	S2 · Synthesis of CoNi MOFs on Ni foam

Complete recipeSource: SI

Route 5: Other

S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11

Metal precursorsCo(NO3)2.6H2O plus Zn(NO3)2.6H2O

Linker precursors2-methylimidazole

SolventsDI water; substrate cleaned with 3 M HCl, ethanol and DI water

Atmospherenot specified

Temperatureroom temperature; dry at 60 deg C

Time4 h reaction; dried overnight

Substrate orientationNi foam substrate

Work-upCleaned with DI water and dried at 60 deg C overnight.

ActivationElectrochemical activation by CV before OER testing, not part of synthesis.

Scalability contextPrepared by the same solution method as CoNi MOFs.

Show 4 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Co(NO3)2.6H2O	40 mL solution A · 0.04 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Metal Source	Zn(NO3)2.6H2O	replacement for Ni(NO3)2.6H2O · 0.01 M inferred from same way	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Linker	2-methylimidazole	40 mL · 0.4 M	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11
Other	Ni foam	2 cm x 5 cm in parent recipe	S2-S3 · Synthesis of CoNi MOFs on Ni foam · Fig. S8-S11

Partial recipeSource: SI

Route 6: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Metal precursorsCorresponding CoM MOFs and Fe(NO3)3.9H2O

Linker precursorsResidual 2-methylimidazole linkers from CoM MOFs

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h inferred from same ultrafast transformation

Substrate orientationCoM MOFs on Ni foam

Oxidant / reductantFe3+ incorporation

Work-upPrepared by immersing corresponding CoM MOFs into the Fe solution; workup follows Fe-CoNi route.

ActivationElectrochemical CV activation before OER testing.

Scalability contextDemonstrates universality across M = Cu, Mn, Cd and Zn.

Show 2 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	same Fe-CoNi route · 0.1 M inferred from corresponding solution	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15
Other	CoM MOFs (M = Cu, Mn, Cd, Zn)	Not specified	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Partial recipeSource: SI

Route 7: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Metal precursorsCorresponding CoM MOFs and Fe(NO3)3.9H2O

Linker precursorsResidual 2-methylimidazole linkers from CoM MOFs

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h inferred from same ultrafast transformation

Substrate orientationCoM MOFs on Ni foam

Oxidant / reductantFe3+ incorporation

Work-upPrepared by immersing corresponding CoM MOFs into the Fe solution; workup follows Fe-CoNi route.

ActivationElectrochemical CV activation before OER testing.

Scalability contextDemonstrates universality across M = Cu, Mn, Cd and Zn.

Show 2 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	same Fe-CoNi route · 0.1 M inferred from corresponding solution	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15
Other	CoM MOFs (M = Cu, Mn, Cd, Zn)	Not specified	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Partial recipeSource: SI

Route 8: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Metal precursorsCorresponding CoM MOFs and Fe(NO3)3.9H2O

Linker precursorsResidual 2-methylimidazole linkers from CoM MOFs

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h inferred from same ultrafast transformation

Substrate orientationCoM MOFs on Ni foam

Oxidant / reductantFe3+ incorporation

Work-upPrepared by immersing corresponding CoM MOFs into the Fe solution; workup follows Fe-CoNi route.

ActivationElectrochemical CV activation before OER testing.

Scalability contextDemonstrates universality across M = Cu, Mn, Cd and Zn.

Show 2 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	same Fe-CoNi route · 0.1 M inferred from corresponding solution	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15
Other	CoM MOFs (M = Cu, Mn, Cd, Zn)	Not specified	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Complete recipeSource: Both

Route 9: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. 1a; Fig. S18

Metal precursorsCoNi MOFs on Ni foam and Fe(NO3)3.9H2O

Linker precursorsExisting 2-methylimidazole linkers partially retained/reprecipitated

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h

Substrate orientationOne CoNi MOFs/Ni foam piece, 0.3 cm x 2 cm

Oxidant / reductantFe3+ source; hydrolysis provides acidic etching/redeposition medium

Work-upQuickly removed from solution and dried in air; used directly as OER electrode.

ActivationElectrochemical CV activation before OER testing.

Scalability contextThe same ultrafast room-temperature method produced a 10 cm x 10 cm Fe-CoNi MOFs electrode.

Show 3 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	10 mL · 0.1 M	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. 1a; Fig. S18
Solvent	water	aqueous	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. 1a; Fig. S18
Other	CoNi MOFs supported on Ni foam	0.3 cm x 2 cm	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. 1a; Fig. S18

Partial recipeSource: SI

Route 10: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18

Metal precursorsCoNi MOFs on Ni foam and Fe(NO3)3.9H2O concentration variant

Linker precursorsExisting 2-methylimidazole linkers partially retained/reprecipitated

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h

Substrate orientationOne CoNi MOFs/Ni foam piece, 0.3 cm x 2 cm

Oxidant / reductantFe3+ source; hydrolysis provides acidic etching/redeposition medium

Work-upQuickly removed from solution and dried in air; used directly as OER electrode.

ActivationElectrochemical CV activation before OER testing.

Scalability contextThe same ultrafast room-temperature method produced a 10 cm x 10 cm Fe-CoNi MOFs electrode.

Show 3 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	10 mL · 0.05 M	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18
Solvent	water	aqueous	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18
Other	CoNi MOFs supported on Ni foam	0.3 cm x 2 cm	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18

Partial recipeSource: SI

Route 11: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18

Metal precursorsCoNi MOFs on Ni foam and Fe(NO3)3.9H2O concentration variant

Linker precursorsExisting 2-methylimidazole linkers partially retained/reprecipitated

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h

Substrate orientationOne CoNi MOFs/Ni foam piece, 0.3 cm x 2 cm

Oxidant / reductantFe3+ source; hydrolysis provides acidic etching/redeposition medium

Work-upQuickly removed from solution and dried in air; used directly as OER electrode.

ActivationElectrochemical CV activation before OER testing.

Scalability contextThe same ultrafast room-temperature method produced a 10 cm x 10 cm Fe-CoNi MOFs electrode.

Show 3 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	10 mL · 0.15 M	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18
Solvent	water	aqueous	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18
Other	CoNi MOFs supported on Ni foam	0.3 cm x 2 cm	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18

Partial recipeSource: SI

Route 12: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18

Metal precursorsCoNi MOFs on Ni foam and Fe(NO3)3.9H2O concentration variant

Linker precursorsExisting 2-methylimidazole linkers partially retained/reprecipitated

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h

Substrate orientationOne CoNi MOFs/Ni foam piece, 0.3 cm x 2 cm

Oxidant / reductantFe3+ source; hydrolysis provides acidic etching/redeposition medium

Work-upQuickly removed from solution and dried in air; used directly as OER electrode.

ActivationElectrochemical CV activation before OER testing.

Scalability contextThe same ultrafast room-temperature method produced a 10 cm x 10 cm Fe-CoNi MOFs electrode.

Show 3 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	10 mL · 0.20 M	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18
Solvent	water	aqueous	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18
Other	CoNi MOFs supported on Ni foam	0.3 cm x 2 cm	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S18

Partial recipeSource: Both

Route 13: Other

17559 · Results and discussion · Fig. S34

Metal precursorsCoNi MOFs on Ni foam and Fe(NO3)3.9H2O

Linker precursorsExisting 2-methylimidazole linkers partially retained/reprecipitated

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h

Substrate orientationLarge Ni foam electrode, 10 cm x 10 cm

Oxidant / reductantFe3+ source; hydrolysis provides acidic etching/redeposition medium

Work-upQuickly removed from solution and dried in air; used directly as OER electrode.

ActivationElectrochemical CV activation before OER testing.

Scalability contextLarge-size 10 cm x 10 cm Fe-CoNi MOFs electrode obtained by the same ultrafast room-temperature method.

Show 3 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	10 mL · 0.1 M	17559 · Results and discussion · Fig. S34
Solvent	water	aqueous	17559 · Results and discussion · Fig. S34
Other	CoNi MOFs supported on Ni foam	10 cm x 10 cm electrode (scaled route; volumes not restated)	17559 · Results and discussion · Fig. S34

Partial recipeSource: SI

Route 14: Other

S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Metal precursorsCorresponding CoM MOFs and Fe(NO3)3.9H2O

Linker precursorsResidual 2-methylimidazole linkers from CoM MOFs

SolventsAqueous Fe(NO3)3 solution

Atmosphereair drying; reaction atmosphere otherwise not specified

Temperatureroom temperature

Time0.000833 h inferred from same ultrafast transformation

Substrate orientationCoM MOFs on Ni foam

Oxidant / reductantFe3+ incorporation

Work-upPrepared by immersing corresponding CoM MOFs into the Fe solution; workup follows Fe-CoNi route.

ActivationElectrochemical CV activation before OER testing.

Scalability contextDemonstrates universality across M = Cu, Mn, Cd and Zn.

Show 2 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Fe(NO3)3.9H2O	same Fe-CoNi route · 0.1 M inferred from corresponding solution	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15
Other	CoM MOFs (M = Cu, Mn, Cd, Zn)	Not specified	S3 · Conversion of CoNi MOFs into Fe-CoNi MOFs · Fig. S12-S15

Complete recipeSource: SI

Route 15: Drop Cast

S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam

Metal precursorsCommercial RuO2 or IrO2

SolventsEthanol and DI water

AdditivesNafion 117 solution, 5 wt%

Atmosphereair-dried overnight

Temperatureroom temperature

Time0.5 h ultrasonication; 2 h soaking; overnight drying

Substrate orientationNi foam, about 1 cm^2, placed inside sealed tube and swayed several times

Work-upNi foam taken out and air-dried overnight.

Show 5 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	commercial IrO2	40 mg	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Additive	Nafion	60 uL · 117 solution, 5 wt%	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Solvent	ethanol	540 uL	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Solvent	DI water	400 uL	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Other	Ni foam	about 1 cm^2	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam

Complete recipeSource: SI

Route 16: Drop Cast

S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam

Metal precursorsCommercial RuO2 or IrO2

SolventsEthanol and DI water

AdditivesNafion 117 solution, 5 wt%

Atmosphereair-dried overnight

Temperatureroom temperature

Time0.5 h ultrasonication; 2 h soaking; overnight drying

Substrate orientationNi foam, about 1 cm^2, placed inside sealed tube and swayed several times

Work-upNi foam taken out and air-dried overnight.

Show 5 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	commercial RuO2/IrO2	40 mg	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Additive	Nafion	60 uL · 117 solution, 5 wt%	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Solvent	ethanol	540 uL	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Solvent	DI water	400 uL	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam
Other	Ni foam	about 1 cm^2	S3 · Preparation of RuO2 and IrO2 electrodes on Ni foam