Photo- and Thermo-chromic Dual-responsive Materials: A Review on Design Strategies and Applications in Smart Windows

doi:10.15541/jim20250361

Abstract

Abstract:

With the continuous growth of the global population and accelerated advancement of industrialization, energy consumption in the construction sector has been rising steadily. Energy conservation and consumption reduction have become a key task for this field to achieve the "dual carbon" goals. As a central component for photothermal exchange within buildings, the thermal insulation and daylighting performance of windows directly determine the energy consumption for regulating the indoor thermal environment, and play a decisive role in the overall energy-saving efficiency of buildings. Traditional energy-saving windows are limited by their static structure, rendering them ill-suited to adapt to changing environments. Smart windows with single-stimulus response, characterized by their singular regulation mode, cannot meet the diversified energy-saving demands. In contrast, photo-thermal dual-responsive smart windows can simultaneously and accurately respond to changes in external light intensity and temperature, realizing dynamic and coordinated regulation of light transmission and heat conduction. This innovation provides an effective solution for building energy conservation. This review systematically summarizes the latest research progress of photo-thermal dual-responsive materials and their smart windows, focusing on three core design strategies: firstly, single-component photo-thermal dual-responsive materials with functional synergy; secondly, photo-thermal dual-responsive multi-component composites integrating photochromic and thermochromic properties; thirdly, coupled systems of photothermal materials and thermochromic materials. For each strategy, the design concept, microstructural characteristics, and photo-thermal dual-responsive color-changing mechanism are elaborated in detail. Meanwhile, the application potential of photo-thermal dual-responsive smart windows in actual building scenarios is deeply discussed, the current technical challenges are systematically analyzed, and the future development prospects are prospected. This review aims to provide comprehensive theoretical references and practical guidance for the structural design optimization, performance improvement, and engineering development of photo-thermal dual-responsive smart windows, thereby promoting the innovation and industrial upgrading of building energy-saving technologies.

Key words: photochromic, thermochromic, dual-responsive material, smart window, zero-energy building, review

CLC Number:

TB34

CHEN Mingjun, MIAO Hongkang, XIAO Yingjun, DENG Jianbo, ZHANG Xiang, ZHAO Jiupeng, LI Yao. Photo- and Thermo-chromic Dual-responsive Materials: A Review on Design Strategies and Applications in Smart Windows[J]. Journal of Inorganic Materials, 2026, 41(6): 723-738.

Figures/Tables 11

References 72

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Photo- and thermo-chromic dual-responsive materials			PC performance			TC performance
Photo- and thermo-chromic dual-responsive materials			Stimulus-response condition	Optical modulation or color change	Response time	Stimulus- response condition	Optical modulation or color change
Single- component material	Organic functional molecule	Salicylaldehyde Schiff base^[31]	Irradiation with 365 nm UV light	White to red	—	Heating at 90 ℃	White to yellow
		Spiropyran derivative^[33]	Irradiation with UV light (365 nm) or visible light (>420 nm)	Purplish red to colorless	60 s (UV light), 12 min (visible light)	Heating at 60 ℃	Colorless to purplish red
		Viologen derivativer^[35]	Irradiation with UV light	Yellow to light green	20 s	Heating at 120-170 ℃	Yellow to light green and dark green
	Inorganic transition metal oxide	ZnSe-doped MoO₃^[36]	Irradiation with UV light	Pale-yellow to blue	180 min	Heating at 23-125 ℃	Pale-yellow to deep blue
	Inorganic transition metal oxide	Oxygen-deficient MoO₃^[37]	Irradiation with UV light	Colorless to dark blue	180 min	Heating at 250 ℃	Colorless to dark blue
	Perovskite material	PZNNT ceramic^[41]	Irradiation with 395 nm UV light	~9% (∆R)	120 s	Heating at 250 ℃ for 10 min	~8% (∆R)
	Perovskite material	Cs₂ZrCl₆:Bi^3+[43]	Irradiation with 254 nm UV light	~27% (∆R)	20 min	365 nm excitation after being kept at 250 ℃	Blue to cyan
Multicomponent composite material	All-organic complex	Mixing TC with PC organic pigment^[44]	Irradiation with UV light	Purple to blue	—	Heating from 31 to 45 ℃	Purple to green and then to colorless
	All-organic complex	Host-guest complex CBV-CD^[45]	Irradiation with 365 nm UV light	Colorless to blue	7 s	Heating from 25 to 100 ℃	Colorless to reddish brown
	All-inorganic composite film	MoO₃/CdS^[46]	Irradiation with a 100 W tungsten lamp	1.8 (∆OD)	45-180 min	Heating from 100 to 225 ℃	1.0 (∆OD)
	All-inorganic composite film	MoO₃/CdSe and CdSe/MoO₃^[47]	Irradiation with 254 nm UV light	0.7 (∆A)	180 min	Heating from 25 to 225 ℃	1.0 (∆A)
	Organic- inorganic composite film	W₁₈O₄₉/PAM-PNIPAM hydrogel^[27]	Irradiation with UV light	34.6% (∆T_lum)	20 min	Heating from 20 to 40 ℃	79.49% (∆T_lum)
Integrated system combining TC material with photo-thermal material	Carbon-based photothermal material	PNDV hydrogel & GO^[52]	Solar irradiation of 22.8 mW/cm²	Colorless to yellow	—	Heating at 40 ℃	Transparent to opaque
	Carbon-based photothermal material	HPMC & CDs^[54]	Solar irradiation of 100 mW/cm²	65.6% (∆T_sol)	5 min	Heating at 33 ℃	Transparent to opaque
	Nobel metal nanoparticles photothermal material	PNIPAm hydrogel & 1D Au nanochain^[55]	Solar irradiation of 2.8 kW·m⁻²	80% (∆T)	2 h	Heating from 20 to 40 ℃	80% (∆T)
	Nobel metal nanoparticles photothermal material	PNIPAm hydrogel & Ag nanowire^[28]	Solar irradiation of 800 W/m²	58.4% (∆T_sol)	40 min	Heating from 25 to 40 ℃	58.4% (∆T_sol)
	Semiconductor nanocrystal photothermal material	VO₂ & Cu₇S₄^[60]	Infrared light irradiation of 100 W	Transparent to opaque	3 min	Heating at 70 ℃	12.3% (∆T_sol)
	Semiconductor nanocrystal photothermal material	PVA-PNIPAM & LimCsnWO₃^[64]	Near-infrared light irradiation	Transparent light blue to translucent blue	—	Heating at 50℃	50.7% (∆T_vis)
	Other photothermal material	PNIPAm hydrogel & PDAPs^[70]	Solar irradiation	87.6% (∆T_lum)	33 s	Heating from 20 to 40 ℃	87.6% (∆T_lum)
	Other photothermal material	PAD hydrogel & Ti₃C₃T_xMXene/GO^[72]	One-sun illumination	Transparent to opaque	—	Heating at 37.7 ℃	67.6% (∆T_lum)

Photo- and thermo-chromic dual-responsive materials			PC performance			TC performance
Photo- and thermo-chromic dual-responsive materials			Stimulus-response condition	Optical modulation or color change	Response time	Stimulus- response condition	Optical modulation or color change
Single- component material	Organic functional molecule	Salicylaldehyde Schiff base^[31]	Irradiation with 365 nm UV light	White to red	—	Heating at 90 ℃	White to yellow
		Spiropyran derivative^[33]	Irradiation with UV light (365 nm) or visible light (>420 nm)	Purplish red to colorless	60 s (UV light), 12 min (visible light)	Heating at 60 ℃	Colorless to purplish red
		Viologen derivativer^[35]	Irradiation with UV light	Yellow to light green	20 s	Heating at 120-170 ℃	Yellow to light green and dark green
	Inorganic transition metal oxide	ZnSe-doped MoO₃^[36]	Irradiation with UV light	Pale-yellow to blue	180 min	Heating at 23-125 ℃	Pale-yellow to deep blue
	Inorganic transition metal oxide	Oxygen-deficient MoO₃^[37]	Irradiation with UV light	Colorless to dark blue	180 min	Heating at 250 ℃	Colorless to dark blue
	Perovskite material	PZNNT ceramic^[41]	Irradiation with 395 nm UV light	~9% (∆R)	120 s	Heating at 250 ℃ for 10 min	~8% (∆R)
	Perovskite material	Cs₂ZrCl₆:Bi^3+[43]	Irradiation with 254 nm UV light	~27% (∆R)	20 min	365 nm excitation after being kept at 250 ℃	Blue to cyan
Multicomponent composite material	All-organic complex	Mixing TC with PC organic pigment^[44]	Irradiation with UV light	Purple to blue	—	Heating from 31 to 45 ℃	Purple to green and then to colorless
	All-organic complex	Host-guest complex CBV-CD^[45]	Irradiation with 365 nm UV light	Colorless to blue	7 s	Heating from 25 to 100 ℃	Colorless to reddish brown
	All-inorganic composite film	MoO₃/CdS^[46]	Irradiation with a 100 W tungsten lamp	1.8 (∆OD)	45-180 min	Heating from 100 to 225 ℃	1.0 (∆OD)
	All-inorganic composite film	MoO₃/CdSe and CdSe/MoO₃^[47]	Irradiation with 254 nm UV light	0.7 (∆A)	180 min	Heating from 25 to 225 ℃	1.0 (∆A)
	Organic- inorganic composite film	W₁₈O₄₉/PAM-PNIPAM hydrogel^[27]	Irradiation with UV light	34.6% (∆T_lum)	20 min	Heating from 20 to 40 ℃	79.49% (∆T_lum)
Integrated system combining TC material with photo-thermal material	Carbon-based photothermal material	PNDV hydrogel & GO^[52]	Solar irradiation of 22.8 mW/cm²	Colorless to yellow	—	Heating at 40 ℃	Transparent to opaque
	Carbon-based photothermal material	HPMC & CDs^[54]	Solar irradiation of 100 mW/cm²	65.6% (∆T_sol)	5 min	Heating at 33 ℃	Transparent to opaque
	Nobel metal nanoparticles photothermal material	PNIPAm hydrogel & 1D Au nanochain^[55]	Solar irradiation of 2.8 kW·m⁻²	80% (∆T)	2 h	Heating from 20 to 40 ℃	80% (∆T)
	Nobel metal nanoparticles photothermal material	PNIPAm hydrogel & Ag nanowire^[28]	Solar irradiation of 800 W/m²	58.4% (∆T_sol)	40 min	Heating from 25 to 40 ℃	58.4% (∆T_sol)
	Semiconductor nanocrystal photothermal material	VO₂ & Cu₇S₄^[60]	Infrared light irradiation of 100 W	Transparent to opaque	3 min	Heating at 70 ℃	12.3% (∆T_sol)
	Semiconductor nanocrystal photothermal material	PVA-PNIPAM & LimCsnWO₃^[64]	Near-infrared light irradiation	Transparent light blue to translucent blue	—	Heating at 50℃	50.7% (∆T_vis)
	Other photothermal material	PNIPAm hydrogel & PDAPs^[70]	Solar irradiation	87.6% (∆T_lum)	33 s	Heating from 20 to 40 ℃	87.6% (∆T_lum)
	Other photothermal material	PAD hydrogel & Ti₃C₃T_xMXene/GO^[72]	One-sun illumination	Transparent to opaque	—	Heating at 37.7 ℃	67.6% (∆T_lum)