Environmentally stable, photochromic and thermotropic organohydrogels for low cost on-demand optical devices

Zhang, Zhuo; Guo, Luxuan; Zhang, Xiaolai; Hao, Jingcheng

doi:10.1016/j.jcis.2020.05.110

Cited by 28 publications

(21 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, one of the challenges involves tuning or shifting the wavelength selectivity window to ensure it only responds to specific wavelengths in the UV spectrum. Currently, applications involving smart windows, [ 33 ] photo‐controlled imaging, [ 276 ] optical, [ 277 ] and optoelectronic [ 278 ] systems rely on visible light, as opposed to UV stimuli. In order to shift the wavelength selectivity to the UV spectrum, photochromic oxides sensitive to UV could be composited with organic materials to form hybrid photochromic systems that are UV sensitive.…”

Section: Outlook and Challengesmentioning

confidence: 99%

UV Photochromism in Transition Metal Oxides and Hybrid Materials

Kayani

Kuriakose

Monshipouri

et al. 2021

Small

View full text Add to dashboard Cite

Limited levels of UV exposure can be beneficial to the human body. However, the UV radiation present in the atmosphere can be damaging if levels of exposure exceed safe limits which depend on the individual the skin color. Hence, UV photochromic materials that respond to UV light by changing their color are powerful tools to sense radiation safety limits. Photochromic materials comprise either organic materials, inorganic transition metal oxides, or a hybrid combination of both. The photochromic behavior largely relies on charge transfer mechanisms and electronic band structures. These factors can be influenced by the structure and morphology, fabrication, composition, hybridization, and preparation of the photochromic materials, among others. Significant challenges are involved in realizing rapid photochromic change, which is repeatable, reversible with low fatigue, and behaving according to the desired application requirements. These challenges also relate to finding the right synergy between the photochromic materials used, the environment it is being used for, and the objectives that need to be achieved. In this review, the principles and applications of photochromic processes for transition metal oxides and hybrid materials, photocatalytic applications, and the outlook in the context of commercialized sensors in this field are presented.

show abstract

Section: Outlook and Challengesmentioning

confidence: 99%

UV Photochromism in Transition Metal Oxides and Hybrid Materials

Kayani

Kuriakose

Monshipouri

et al. 2021

Small

View full text Add to dashboard Cite

show abstract

“…Since different amount of water were used as cosolvent in the preparation of the binary metal oxide nanocomposites, the effect could also be observed on the photochromic enhancement of the hydrogel (Figure 8E), 67 with HZ 0.1 exhibiting intense coloration (blue-black) response at 60 s irradiation exposure, compared to previously reported coloration whose changes were either light green or blue. 10,[25][26][27] The presence of physioÀ/ chemisorbed water can radically enhance the photochromic sensitivity of the as-prepared hydrogel due to formation of water wires that can serve as proton pathways to promote the diffusion of nascent protons, as the photospillover of hydrogen between binary metal oxide and polymeric monomers (AM and HEA) can be also be used for the engineering of the photochromic structures with various performances. 68,69 Figure 8C shows the relationship between the absorption peak and the irradiation time which is obtained by the fitting A = A 0 + 0.0035t i , (R 2 = 0.977), where A 0 is the absorption of the hydrogel after 5 s UV irradiation exposure, and A being the absorption of hydrogel after the irradiation of t i s afterwards.…”

Section: Transparency and Photochromism Of The Hydrogelsmentioning

confidence: 99%

“…The hydrogel was evaluated for the degradation of rhodamine B (RhB) and was found to exhibit remarkable photocatalytic performance of 98% in 1 h, respectively, under visible light irradiation. Additionally, Zhang et al 25 synthesized photochromic/ thermotropic organohydrogels (PTOs) consisting of polyacrylamide and cellulose. The final organohydrogels, which were obtained by soaking in Mo7, was reported to exhibit fast photochromism (in 10 s) as well as durable thermoresponsivity, distinct anti-freezing (À30 C) and anti-dehydration performances.…”

mentioning

confidence: 99%

“…The final organohydrogels, which were obtained by soaking in Mo7, was reported to exhibit fast photochromism (in 10 s) as well as durable thermoresponsivity, distinct anti-freezing (À30 C) and anti-dehydration performances. Furthermore, Guan et al, 10 Yang et al, 26,27 and Zhang et al 25 reported direct dispersion or immersion of commercially sourced molybdenum precursor reagent into the hydrogel matrix to achieve photochromism. On another hand, there are relatively few reports on thermochromic hydrogel based on semiconductor metal oxides.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and properties of low‐cost, photochromic transparent hydrogel based on ethaline‐assisted binary tungsten oxide‐molybdenum oxide nanocomposite for optical memory applications

Oderinde

Ejeromedoghene

2021

Polymers for Advanced Techs

View full text Add to dashboard Cite

Tungsten oxide-based composites are important smart materials for wider usage in efficient energy windows, rewritable inks and other colored displays. However, the problem of agglomeration has made it challenging to be employed in transparent, photo-reversible materials especially in functional hydrogels. We herein report the preparation of high transparent hydrogel using water-soluble tungsten oxidemolybdenum oxide nanocomposites. The hydrogel was characterized with FTIR, TGA, XPS, SEM, and UV-Vis-NIR, while the mechanical properties were also analyzed. The FTIR confirmed that the metal oxides combined with the polymer units via strong metaloxygen bond. For the TGA, the as-prepared hydrogel was still able to maintain a weight loss of 18.12% at 500 C compared to 10.45% for pristine hydrogel. Also, the EDX mapping revealed microscopic metal oxides particles sizes, without any cluster phenomenon appearance. Additionally, the as-prepared hydrogel revealed good mechanical properties as it could sustain a high deformation ratio (λ) of 86.3% at a stress of 60.3 MPa due to hydrogen bond crosslinking and ionic bond linkages. Moreover, the hydrogel exhibited high percentage transmittance (T%) of ~83%, as well as remarkable photochromic response, with absorption peaks at ~490, ~630 and ~730 nm appearing as the exposure time of the UV light increases. Furthermore, change in color was observed in 5 s, deepening to deep blue-black at 300 s exposure to UV, while complete reverse fading was achieved in ~6 h in ambient air without external stimulus, hence making it a good potential for applications in various optical memory, sensors and rewritable devices.

show abstract

“…[ 7–9 ] In recent years, photochromic molecules such as lanthanide ions, polymetallic oxides, diarylvinyl, azobenzene, and spiropyran have been widely used in the construction of photochromic hydrogels. Strategies for integration of photochromic moieties into hydrogel structures include dynamic coordination, [ 10 ] in situ copolymerization, [ 11 ] dynamic host–guest interactions, [ 12 ] and micelle‐copolymerization. [ 13 ] However, both the time‐consuming preparation process and the weak mechanical properties of conventional photo‐responsive hydrogels greatly limit their use of information records.…”

Section: Introductionmentioning

confidence: 99%

High‐Performance Photochromic Hydrogels for Rewritable Information Record

Long

Jin

et al. 2021

Macromol. Rapid Commun.

View full text Add to dashboard Cite

Rewritable information record materials usually demand not only reversibly stimuli‐responsive ability, but also strong mechanical properties. To achieve one photochromic hydrogel with super‐strong mechanical strength, hydrophobic molecule spiropyran (SP) has been introduced into a copolymer based on ion‐hybrid crosslink. The hydrogels exhibit both photoinduced reversible color changes and excellent mechanical properties, i.e., the tensile stress of 3.22 MPa, work of tension of 12.8 MJ m−3, and modulus of elasticity of 8.6 MPa. Moreover, the SP‐based Ca2+ crosslinked hydrogels can be enhanced further when exposed to UV‐light via ionic interaction coordination between Ca2+, merocyanine (MC) with polar copolymer chain. In particular, hydrogels have excellent reversible conversion behavior, which can be used to realize repeatable writing of optical information. Thus, the novel design is demonstrated to support future applications in writing repeatable optical information, optical displays, information storage, artificial intelligence systems, and flexible wearable devices.

show abstract

Environmentally stable, photochromic and thermotropic organohydrogels for low cost on-demand optical devices

Cited by 28 publications

References 37 publications

UV Photochromism in Transition Metal Oxides and Hybrid Materials

UV Photochromism in Transition Metal Oxides and Hybrid Materials

Synthesis and properties of low‐cost, photochromic transparent hydrogel based on ethaline‐assisted binary tungsten oxide‐molybdenum oxide nanocomposite for optical memory applications

High‐Performance Photochromic Hydrogels for Rewritable Information Record

Contact Info

Product

Resources

About