Synthesis and structure of [C{sub 6}N{sub 4}H{sub 20}]{sub 0.5}[B{sub 5}O{sub 6}(OH){sub 4}]: A new organically templated pentaborate with white-light-emission

A new organically templated pentaborate [C{sub 6}N{sub 4}H{sub 20}]{sub 0.5}[B{sub 5}O{sub 6}(OH){sub 4}] (1a) was prepared by reactions of triethylenetetramine (TETA) with excess boric acid in aqueous solution and characterized by elemental analysis, FTIR, TG-DTA, powder X-ray diffraction and photoluminescence spectroscopy. The structure of 1a was determined by a single-crystal X-ray diffraction. It crystallizes in the monoclinic system with space group P2(1)/c, a=9200(3) A, b=14.121(5) A, c=10.330(4) A, {beta}=91.512(4){sup o}, V=1341.4(9) A{sup 3}, and Z=4. The luminescent properties of the compound were studied, and a green-blue luminescence occurs with an emission maximum at 507 nm upon excitation at 430 nm. The photoluminescence of 1a can be modified from green-blue to white by means of a simple heat-treatment process. The white-light-emission of sample 1c makes the pentaborate a good candidate for display and lighting applications in the white LED. - Graphical abstract: A green-blue luminescence occurs with an emission maximum at 507 nm upon excitation at 430 nm. The photoluminescence of 1a can be modified from green-blue to white by means of a simple heat-treatment process. Highlights: > A new organically templated pentaborate [C{sub 6}N{sub 4}H{sub 20}]{sub 0.5}[B{sub 5}O{sub 6}(OH){sub 4}] has been prepared. > The structure of the compound is determined by single-crystal X-ray diffraction. > Elemental analysis, FTIR, TG-DTA, powder X-ray diffraction and photoluminescence spectroscopy of the compound is investigated. > The photoluminescence of the compound can be modified from green-blue to white by means of a simple heat-treatment process. > The TETA molecules were diprotonated and located in the channels isolatedly as templates and counterions to compensate the negative charges of the framework.