Structural transformation of selenidostannates from 1D to 0D and 2D via a stepwise amine-templated assembly strategy

Abstract

We investigated the amine-induced structure transformation of four selenidostannates, i.e. [Sn₃Se₇Fe(TEPA)]_n (1), {[Sn₂Se₆]·4(H⁺-PR)} (2), {[Sn₂Se₆]·2[Fe(en)₃]} (3), and {[Sn₃Se₇]_n·2n(H⁺-DBN)} (4) (TEPA = tetraethylenepentamine, PR = piperidine, en = ethylenediamine, DBN = 1,5-diazabicyclo[4.3.0]non-5-ene), which were characterized by single-crystal X-ray diffraction and UV-vis spectroscopy. The TEPA-induced 1D chain structure of [Sn₃Se₇Fe(TEPA)]_n in 1 can undergo cleavage of Se–Fe and Se–Sn bonds to form a 0D dimer unit of [Sn₂Se₆]²⁻ observed in 2 and 3, induced by PR and en, respectively. More interestingly, under the induction of en and DBN templates, such a 1D chain can counterintuitively fuse into a 2D layered structure of [Sn₃Se₇]_n²ⁿ⁻ through the removal of [Fe(TEPA)] species and reformation of Sn–Se bonds. Moreover, these selenidostannates with different structural dimensionalities display photocurrent responses, which make them hold some promise as a potential semiconducting material applied in photoelectric devices.