Luminescent kappa-Carrageenan-Based Electrolytes Containing Neodymium Triflate

authors	Nunes, SC; Saraiva, SM; Pereira, RFP; Silva, MM; Carlos, LD; Almeida, P; Goncalves, MC; Ferreira, RAS; Bermudez, VD
nationality	International
journal	MOLECULES
author keywords	kappa-carrageenan; structure; biopolymer electrolyte; thermal properties; ionic conductivity; luminescence features
keywords	IOTA-CARRAGEENAN; POLYMER ELECTROLYTE; GEL ELECTROLYTE; SMART WINDOWS; BIOPOLYMER; CONDUCTIVITY; CHITOSAN; TRANSITION; DEVICES
abstract	In recent years, the synthesis of polymer electrolyte systems derived from biopolymers for the development of sustainable green electrochemical devices has attracted great attention. Here electrolytes based on the red seaweeds-derived polysaccharide kappa-carrageenan (kappa-Cg) doped with neodymium triflate (NdTrif(3)) and glycerol (Gly) were obtained by means of a simple, clean, fast, and low-cost procedure. The aim was to produce near-infrared (NIR)-emitting materials with improved thermal and mechanical properties, and enhanced ionic conductivity. Cg has a particular interest, due to the fact that it is a renewable, cost-effective natural polymer and has the ability of gelling in the presence of certain alkali- and alkaline-earth metal cations, being good candidates as host matrices for accommodating guest cations. The as-synthesised kappa-Cg-based membranes are semi-crystalline, reveal essentially a homogeneous texture, and exhibit ionic conductivity values 1-2 orders of magnitude higher than those of the kappa-Cg matrix. A maximum ionic conductivity was achieved for 50 wt.% Gly/kappa-Cg and 20 wt.% NdTrif(3)/kappa-Cg (1.03 x 10(-4), 3.03 x 10(-4), and 1.69 x 10(-4) S cm(-1) at 30, 60, and 97 degrees C, respectively). The NdTrif-based kappa-Cg membranes are multi-wavelength emitters from the ultraviolet (UV)/visible to the NIR regions, due to the kappa-Cg intrinsic emission and to Nd3+, F-4(3/2)-> I-4(11/2-9/2).
publisher	MDPI
issn	1420-3049
year published	2019
volume	24
issue	6
digital object identifier (doi)	10.3390/molecules24061020
web of science category	Biochemistry & Molecular Biology; Chemistry, Multidisciplinary
subject category	Biochemistry & Molecular Biology; Chemistry
unique article identifier	WOS:000464290200007