A5029029970- Photochromic and Fluorescence Chemistry
- Organic Electronics and Photovoltaics
- Photoreceptor and optogenetics research
- Electrocatalysts for Energy Conversion
- Graphene research and applications
- 2D Materials and Applications
- Conducting polymers and applications
- Advanced Memory and Neural Computing
- Photochemistry and Electron Transfer Studies
- Transition Metal Oxide Nanomaterials
- Perovskite Materials and Applications
- Advanced biosensing and bioanalysis techniques
- Phase Change Materials Research
- Porphyrin and Phthalocyanine Chemistry
- MXene and MAX Phase Materials
- Neurobiology and Insect Physiology Research
- Solar-Powered Water Purification Methods
Brandeis University
2018-2022
Arylazopyrazole derivatives based on four core structures (4pzMe, 3pzH, 4pzH, and 4pzH-F2) functionalized with a dodecanoate group were demonstrated to store thermal energy in their metastable Z isomer liquid phase release the by optically triggered crystallization at -30 °C for first time. Three heat storage-release schemes discovered involving different activation methods (optical, thermal, or combined) generating liquid-state isomers capable of storing energy. Visible light irradiation...
Photo-responsive organic phase change materials that can absorb filtered solar radiation in the visible range to store both latent heat and photon energy are demonstrated.
The generally small Gibbs free energy difference between the Z and E isomers of hydrazone photoswitches has so far precluded their use in photon storing applications. Here, we report on a series cyclic acyclic hydrazones, which possess varied degrees ring strain and, hence, stability isomers. photoinduced isomerization concurrent phase transition hydrazones from crystalline to liquid result storage large quantity energy, comparable that azobenzene derivatives. We demonstrate macrocyclic...
Azo-based photoswitches have shown promise as molecular solar–thermal (MOST) materials due to their ability store energy in metastable Z isomeric form. The is then released, the form of heat, upon photoisomerization thermodynamically stable E However, obtaining a high density and recovering stored with efficiency requires be employed condensed phase display degree switching, both which are challenging engineer. Here, we show that arylazopyrazole motifs undergo efficient redox-induced...
Compact azobenzene derivatives with various functional groups are investigated to realize total photon and thermal energy storage over 300 J g −1 .
Photoswitching behavior of individual organic molecules was imaged by annular dark-field scanning transmission electron microscopy (ADF-STEM) using a highly beam transparent graphene support. azobenzene derivatives with ligands at each end containing single transition-metal atoms (Pt) were designed (Pt-complex), and the distance between strong ADF-STEM contrast from two Pt in Pt-complex is used to track molecular length changes. UV irradiation induce photoswitching complex on graphene, we...
We use annular dark-field scanning transmission electron microscopy (ADF-STEM) to study how solution-deposited molecules bind the edges and surface regions around nanopores in MoS2 monolayers. Nanopores with clean atomically flat controllable mean diameter were generated by time-dependent large-area beam exposure during an situ heating process, ready for subsequent molecular attachment. An organic molecule was designed have a dithiolane end group that binds Mo-terminated sites ligand...
Isomerization behaviors of spiropyran derivatives in neat condensed phase were studied to understand their unusual transitions including cold-crystallization after extreme supercooling down -50 °C. Compounds with different functional groups compared, and the equilibrium between isomers at high temperatures was found determine transitions.
We present a transition-metal complex containing Pt center, large aromatic ligand, and Mo-binding terminal group, designed to maximize the dispersion of individual molecules across 2D MoS2 substrate. The bulky organic ligand structure shows higher thermal stability than typical halides in inorganic salt, such as H2PtCl6, thus provides number isolated single atoms on surfaces even after annealing up 900 °C. Epitaxially aligned nanocrystals that are 3–5 nm diameter also formed upon treatment,...