Synthesis · A Light-Responsive Metal–Organic Framework Hybrid Membrane with High On/Off Photoswitchable Proton Conductivity

4 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

3,6 · Proton Conductivity Evaluation · Figure S6

Metal precursorsAg electrodes

Additivesconductive silver adhesive for wire connection

Substrate orientationAg electrodes evaporated onto SSP@ZIF-8-10%/AAO membrane surface; membrane connected to external circuit by a 1 m wire

Work-upElectrodes connected with conductive silver adhesive; device placed in temperature and humidity chamber for testing.

ActivationMembranes held at set temperature and humidity for more than 2 h before electrochemical impedance testing.

Show 2 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	Ag electrodes	evaporated with current of 65 A	3,6 · Proton Conductivity Evaluation · Figure S6
Other	conductive silver adhesives	Not specified	3,6 · Proton Conductivity Evaluation · Figure S6

Complete recipeSource: SI

Route 2: Other

1-2 · Experimental Procedures

Linker precursors2,3,3-trimethylindolenine; CH3I; 1,2,3,3-tetramethyl-3H-indolium iodide intermediate; sodium salicylaldehyde-5-sulfonate

Solventsmethanol; ethanol; diethyl ether; chloroform; benzene

Additivespiperidine

AtmosphereN2 for first alkylation step

Temperature60 degC for 2 h, then reflux at 80 degC for 4 h

Time2 h first step; 4 h second step

Work-upFiltered, washed with ethanol and diethyl ether, recrystallised from absolute ethanol; solvent removed under reduced pressure; residue dissolved in chloroform and recrystallised from benzene; dried under reduced pressure.

Show 6 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	2,3,3-Trimethylindolenine	1.6 mL, 10 mmol	1-2 · Experimental Procedures
Other	CH3I	20 mL, 12 mmol	1-2 · Experimental Procedures
Other	1,2,3,3-Tetramethyl-3H-indolium iodide (I)	602.3 mg, 2 mmol	1-2 · Experimental Procedures
Base	piperidine	200 uL, 2 mmol	1-2 · Experimental Procedures
Other	sodium salicylaldehyde-5-sulfonate	448.3 mg, 2 mmol · in 10 mL methanol	1-2 · Experimental Procedures
Solvent	methanol	10 mL plus 10 mL	1-2 · Experimental Procedures

Complete recipeSource: Both

Route 3: Other

2 · Fabrication of SSP@ZIF-8 Membranes on AAO

Metal precursorszinc nitrate hexahydrate converted to zinc hydroxide nanostrands

Linker precursors2-methylimidazole (Hmim); sulfonated spiropyran (SSP)

Solventsethanol/water vol 2:3 for ZHNs; ethanol/water vol 1:4 for Hmim conversion; aqueous SSP solutions

Additives2-aminoethanol in ZHN precursor solution

Atmosphereambient/room temperature; no inert atmosphere stated for membrane fabrication

Temperatureroom temperature

TimeZHNs stirred 5 min and aged 30 min; ZHNs mixed with SSP 5 min; Hmim conversion 24 h

Substrate orientationfiltered onto AAO membrane substrate

Work-upWashed with ethanol/water (vol 1:4) three times to remove residual reactants and dried at room temperature.

ActivationFor N2 sorption characterisation, samples were activated at 100 degC for 12 h.

Scalability contextMembranes prepared by room-temperature filtration/confinement conversion on AAO; no scale-up data reported.

Show 6 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	zinc nitrate (Zn(NO3)2.6H2O)	equal volume to 50 mL 2-aminoethanol solution · 4 mM in ethanol/water (vol 2:3)	2 · Fabrication of SSP@ZIF-8 Membranes on AAO
Additive	2-aminoethanol	50 mL solution · 1.6 mM in ethanol/water (vol 2:3)	2 · Fabrication of SSP@ZIF-8 Membranes on AAO
Other	zinc hydroxide nanostrands (ZHNs) solution	5 mL	2 · Fabrication of SSP@ZIF-8 Membranes on AAO
Additive	SSP aqueous solution for 1%, 5%, 10%, 20% membranes	0.31 mL, 0.15 mL, 0.31 mL, and 0.61 mL, respectively · 0.003 wt%, 0.03 wt%, 0.03 wt%, and 0.03 wt%, respectively	2 · Fabrication of SSP@ZIF-8 Membranes on AAO
Linker	2-methylimidazole (Hmim)	10 mL solution · 25 mM in ethanol/water (vol 1:4)	2 · Fabrication of SSP@ZIF-8 Membranes on AAO
Solvent	ethanol/water	vol 2:3 and vol 1:4 mixtures	2 · Fabrication of SSP@ZIF-8 Membranes on AAO

Partial recipeSource: Both

Route 4: Other

2 · Results and discussion · Figure 2

Metal precursorszinc hydroxide nanostrands from zinc nitrate and 2-aminoethanol

Linker precursors2-methylimidazole (Hmim)

Solventsethanol/water

Additives2-aminoethanol

Atmosphereambient/room temperature; no inert atmosphere stated

Temperatureroom temperature

Time24 h Hmim conversion stated for SSP@ZIF-8 route; pristine ZIF-8 control route not separately written

Substrate orientationAAO membrane

Work-upWashed/dried procedure inferred from membrane fabrication section; pristine control-specific workup not separately stated.

Activation100 degC for 12 h before N2 sorption measurement.

Show 3 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	zinc nitrate (Zn(NO3)2.6H2O)	4 mM in ethanol/water (vol 2:3) for ZHNs preparation	2 · Results and discussion · Figure 2
Additive	2-aminoethanol	1.6 mM in ethanol/water (vol 2:3) for ZHNs preparation	2 · Results and discussion · Figure 2
Linker	2-methylimidazole (Hmim)	10 mL solution in SSP@ZIF-8 route · 25 mM	2 · Results and discussion · Figure 2