High pressure photoluminescence and Raman investigations of Rhodamine B absorbed on MIL 53(Fe)

Encapsulating organic dyes within porous solids is an efficient way to design luminescent composite materials and devices. However, for practice applications, the luminescence tuning and the stability investigation of such materials is still a challenge work. Here, a comparative in situ Raman spectra and photoluminescence (PL) spectra are employed to study the structural and optical property of both pure Rhodamine B (RHB) and samples absorbed on a kind of typical materials of institute lavoisier frameworks (MIL) under high pressure, respectively. The luminescence of RHB@MIL 53(Fe) can persist to pressures much higher than that for pure RHB. Our studies revealed that the PL emissions of RHB origin from monomeric and dimeric structures, respectively. Furthermore, our results indicated that the confining effect of MIL 53(Fe) pores inhibited the dimerization of RHB molecules under high pressure.