Towards developing novel and sustainable molecular light-to-heat converters

Abstract

Light-to-heat conversion materials generate great interest due to their widespread applications, notable exemplars being solar energy harvesting and photoprotection. Another more recently identified potential application for such material is in...

Investigating the Ultrafast Dynamics and Long-Term Photostability of an Isomer Pair, Usujirene and Palythene, from the Mycosporine-like Amino Acid Family

“…Our interest in studying usujirene and palythene stems from the fact these two MAAs (i) are distinct, due to the addition of the conjugated double bond, and may relax via an alternative mechanism compared with other MAAs and (ii) absorb further into the UVA than most MAAs, a spectral region of which there is a lack of UV filters [ 30 ]. Furthermore, it is important to add that efficient molecular photon-to-heat conversion does not solely benefit the cosmetic industry; there are pharmaceutical, energy and environmental uses for such molecules [ 31 , 32 , 33 ].…”

From Biomass-Derived p-Hydroxycinnamic Acids to Novel Sustainable and Non-Toxic Phenolics-Based UV-Filters: A Multidisciplinary Journey

“…The compounds resulting from this modification exhibited drastically improved stability toward UV radiation exposure, while retaining their initial wavelength coverage and level of absorption ( Figure 3 ), making them promising, nature-inspired UV-filters. Furthermore, some strong Brønsted acids, such as Meldrum’s acid or (thio)barbituric acid can also be used to synthesize highly hindered compounds ( Peyrot et al, 2020b ; Abiola et al, 2021a ; Abiola et al, 2021b ; Rioux et al, 2022 ). The high acidity of their hydrogen at the β positions of the two carbonyls allows the implementation of base-free synthetic procedures perfectly fitting green chemistry by using water as solvent and catalyst at room temperature and without the need of purification, as p -hydroxycinnamyl (thio)barbiturics (5) and Meldrum’s (6) readily precipitate in water ( Scheme 1 ).…”

“…ROS, in the form of free radicals, are highly reactive species capable of degrading materials and inducing cellular damage in living organisms (i.e., inflammation, oxidative stress or even carcinogenesis) ( Pillai et al, 2005 ; Austin et al, 2018 ). Phenols, especially the aforementioned p -hydroxycinnamic acids and their derivatives, are known to exhibit interesting antioxidant activity through their high conjugation, facilitating their ability to neutralize free radicals ( Peyrot et al, 2020a ; Peyrot et al, 2020c ; Mention et al, 2020 ; Mouterde et al, 2020 ; Rioux et al, 2020 ; Abiola et al, 2021a ; Abiola et al, 2021b ). Such molecules have proven to be competitive ( Figure 4 , notably those derived from caffeic, ferulic and sinapic acid), against the antioxidants conventionally used and that are strongly criticized for their suspected endocrine toxicity and carcinogenic effect like BHA (butylated hydroxyanisole), BHT (butylated hydroxytoluene) or Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid).…”

“…The three case studies presented here demonstrate how gathering a deep understanding of UV-filter photodynamics has guided the molecular design of plant-based compounds that present ideal physico-chemical properties. This type of bottom-up approach to molecular design has proven valuable in real-life applications from photoprotective cosmetics to light-to-heat conversion materials ( Abiola et al, 2021a ).…”

Intramolecular Phosphine-Promoted Knoevenagel Based Redox-Reaction

“…In some cases the reaction is carried out at room temperature [ 10 ], and in other cases the use of acetic acid as an additive next to a nonpolar solvent like benzene or toluene under reflux conditions was established [ 11 , 12 , 13 , 14 ]. Green alternatives to classical Knoevenagel condensation avoid the use of organic solvents, use catalysts from naturally occurring compounds, improve the atomic economy of the reaction or are carried out at mild reaction conditions that thus reduce energy consumption [ 15 , 16 , 17 , 18 ].…”