Pyrene derivative-functionalized mesoporous silica–Cu2+ hybrid ensemble for fluorescence “turn-on” detection of H2S and logic gate application in aqueous media

The ensemble system PyH-SBA-15-Cu 2+ was obtained via coordination interaction of pyrene derivative-functionalized mesoporous SBA-15 and Cu 2+ , and applied for the selective and sensitive detection of H 2 S over pH 6.0–12.0 in aqueous media. The sensing strategy was designed on the basis of the H 2 S-induced dissolution of Cu 2+ from PyH-SBA-15-Cu 2+ . Cu 2+ has good binding affinity to N atoms in PyH-SBA-15; therefore, the organic–inorganic hybrid ensemble PyH-SBA-15-Cu 2+ was formed, which is nonfluorescent in aqueous solution because of the Cu 2+ -promoted emission quenching of PyH-SBA-15. The addition of H 2 S induces the dissolution of PyH-SBA-15-Cu 2+ by the formation of stable CuS, thereby producing fluorescence revival of PyH-SBA-15. The correlative “turn-on” fluorescence signals of this ensemble system are linearly proportional to [H 2 S] in the concentration region of 0–1.0 × 10 −4 M, showing a low detection limit of 3.7 × 10 −7 M. Other common anions do not induce distinct fluorescence changes. When using the fluorescence intensity signal changes of PyH-SBA-15 as outputs and Cu 2+ and S 2− as inputs, PyH-SBA-15 can act as an XNOR logic gate.