TY - JOUR
T1 - Sustainable Dual-Mode Smart Windows for Energy-Efficient Buildings
AU - Nunes, Sílvia C.
AU - Saraiva, Sofia M.
AU - Pereira, Rui F. P.
AU - Pereira, Sónia
AU - Silva, Maria Manuela
AU - Carlos, Luís D.
AU - Fortunato, Elvira
AU - Ferreira, Rute A. S.
AU - Rego, Rosa
AU - Bermudez, Verónica de Zea
N1 - info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBPD%2F87759%2F2012/PT#
info:eu-repo/grantAgreement/FCT/5876/135918/PT#
This work was supported by FEDER, through COMPETE and Fundacao para a Ciencia e a Tecnologia (FCT) (FCOMP-01-0124-FEDER-037271, and UID/CTM/50025/2019), project LUMECD (POCI-01-0145-FEDER-016884 and PTDC/CTM-NAN/0956/2014), project UniRCell (ref. SAICTPAC/0032/2015, POCI-01-0145-FEDER-016422), and by the Portuguese National NMR Network (RNRMN). S.C.N. acknowledges FCT for grants (Post -PhD Fellowships of UniRCell and LUMECD projects). The authors thank CPKelco (U.S.A.) for providing the x-carrageenan sample.
PY - 2019/3/25
Y1 - 2019/3/25
N2 -
Electrochromic devices (ECDs) combining visible/near-infrared (NIR) transparent amorphous indium zinc oxide (a-IZO) external layers with innovative NIR-emitting electrolytes composed of red seaweed-derived κ-carrageenan (κ-Cg) polysaccharide, glycerol (Gly), and erbium triflate (ErTrif
3
·xH
2
O) are proposed as a valuable technological solution for the development of smart windows providing less heating demand, less glare and more indoors human comfort for the new generation of energy-efficient buildings. The electrolyte preparation is cheap, clean, and fast. The optimized sample including 50 wt% Gly/κ-Cg and 40 wt% ErTrif
3
·xH
2
O/κ-Cg exhibits the highest ionic conductivity (1.5 × 10
-4
S cm
-1
at 20 °C) and displays ultraviolet (UV)/blue and NIR emissions associated with the κ-Cg-based host and the Er
3+
ions (
4
I
15/2
→
4
I
13/2
), respectively. The 5-layer configuration ECD tested demonstrated fast switching time (50 s), high electrochromic contrast (transmittance variations of 46/51% at 550/1000 nm), high optical density change (0.89/0.75 at 550/1000 nm), outstanding coloration efficiency (450th cycle = -15902/-13400 cm
2
C
-1
and +3072/+2589 cm
2
C
-1
at 550/1000 nm for coloration and bleaching, respectively), excellent electrochemical stability, and self-healing after mechanical damage. The ECD encompasses two voltage-operated modes: semibright warm (+3.0 V, transmittances of 52/61% at 550/1000 nm) and dark cold (-3.0 V, transmittances of 7/11% at 550/1000 nm).
AB -
Electrochromic devices (ECDs) combining visible/near-infrared (NIR) transparent amorphous indium zinc oxide (a-IZO) external layers with innovative NIR-emitting electrolytes composed of red seaweed-derived κ-carrageenan (κ-Cg) polysaccharide, glycerol (Gly), and erbium triflate (ErTrif
3
·xH
2
O) are proposed as a valuable technological solution for the development of smart windows providing less heating demand, less glare and more indoors human comfort for the new generation of energy-efficient buildings. The electrolyte preparation is cheap, clean, and fast. The optimized sample including 50 wt% Gly/κ-Cg and 40 wt% ErTrif
3
·xH
2
O/κ-Cg exhibits the highest ionic conductivity (1.5 × 10
-4
S cm
-1
at 20 °C) and displays ultraviolet (UV)/blue and NIR emissions associated with the κ-Cg-based host and the Er
3+
ions (
4
I
15/2
→
4
I
13/2
), respectively. The 5-layer configuration ECD tested demonstrated fast switching time (50 s), high electrochromic contrast (transmittance variations of 46/51% at 550/1000 nm), high optical density change (0.89/0.75 at 550/1000 nm), outstanding coloration efficiency (450th cycle = -15902/-13400 cm
2
C
-1
and +3072/+2589 cm
2
C
-1
at 550/1000 nm for coloration and bleaching, respectively), excellent electrochemical stability, and self-healing after mechanical damage. The ECD encompasses two voltage-operated modes: semibright warm (+3.0 V, transmittances of 52/61% at 550/1000 nm) and dark cold (-3.0 V, transmittances of 7/11% at 550/1000 nm).
KW - energy-efficient glazing for buildings
KW - erbium triflate
KW - glare reduction
KW - heating saving
KW - NIR-emitting smart windows
KW - window daylighting control
KW - κ-carrageenan polysaccharide
UR - http://www.scopus.com/inward/record.url?scp=85059249809&partnerID=8YFLogxK
U2 - 10.1021/acsaem.8b02041
DO - 10.1021/acsaem.8b02041
M3 - Article
AN - SCOPUS:85059249809
VL - 2
SP - 1951
EP - 1960
JO - ACS Applied Energy Materials
JF - ACS Applied Energy Materials
IS - 3
ER -
