Table 1. Synthesis Conditions and Nitrogen Physisorption Data for MSNs of Varying Sizea.
| particle size | [H2O] (M) | [NH3] (M) | [CTAB] (mM) | reaction volume (mL) | temperature (oC) | specific surface area (m2 g–1)b | average pore width (Å)c | nitrogen wt %d |
|---|---|---|---|---|---|---|---|---|
| 30 nm | 54.5 | 0.267 | 5.30 | 150 | 68 ± 1 | 1290 ± 90 | 23.6 ± 2.3 | ≤0.01 |
| 150 nm | 39.4 | 0.267 | 5.30 | 150 | 38 ± 1 | 1170 ± 80 | 21.9 ± 0.6 | 1.11 ± 0.12 |
| 450 nm | 35.0 | 0.267 | 5.30 | 150 | 23 ± 1 | 1280 ± 120 | 20.4 ± 0.2 | 0.13 ± 0.06 |
| 1100 nm | 25.5 | 0.521 | 2.20 | 350 | 23 ± 1 | 1170 ± 70 | 19.5 ± 0.3 | ≤0.01 |
a
Error bars represent standard deviation for n ≥ 3 separate syntheses.
b
Determined by BET analysis of the nitrogen sorption isotherms (0.05 ≤ p/p0 ≤ 0.20).
c
Calculated via BJH analysis of the nitrogen adsorption isotherm (p/p0 ≤ 0.60).
d
Nitrogen wt % measured by elemental analysis.