Linear thiophene-containing π-conjugated aldehydes with aggregation-induced emission for building solid red luminophors

•Linear thiophene-containing π-conjugated aldehydes with aggregation-induced emission characteristic are studied.•Amorphous nanoscale aggregates exhibit distinct aggregation-induced emission behavior.•Efficient solid red luminophor is achieved from the linear AIE aldehyde.

Two linear thiophene-containing π-conjugated aldehydes 4-(thiophen-2-yl)benzaldehyde and 2,5-bis[4-(formyl)phenyl]thiophene exhibiting aggregation-induced emission (AIE) were demonstrated. The photophysical properties of the two aldehydes in solution and THF/H2O mixtures were studied, and aggregates formed with different water fractions were studied by scanning electron microscopy. Results indicated that amorphous nanoscale aggregates exhibit distinct AIE behavior when assembled in solutions with appropriate water contents. Condensation of 1,3-indandione with 4-(thiophen-2-yl)benzaldehyde generated a new luminophor 2-[4-(thiophen-2-yl)benzylidene]-2H-indene-1,3-dione; this product presents as a solid powder that emits intensely red photoluminescence at 620 nm with a quantum yield of 12.8%.

Graphical abstractTwo linear thiophene-containing π-conjugated aldehydes 4-(thiophen-2-yl)benzaldehyde and 2,5-bis[4-(formyl)phenyl]thiophene exhibiting aggregation-induced emission (AIE). Our preliminary work shows that these aldehydes have potential applications in building solid red luminophors.Figure optionsDownload full-size imageDownload as PowerPoint slide