An Artificial Light-Harvesting System with Tunable Fluorescence Color in Aqueous Sodium Dodecyl Sulfonate Micellar Systems for Photochemical Catalysis

Main observation and conclusion In the present work,an artificial light-harvesting system with fluorescence resonance energy transfer(FRET)is successfully fabricated in aqueous sodium dodecyl sulfonate(SDS)micellar systems.Since the tight and orderly arrangement of dodecyl in the SDS micelles is hydrophobic,tetra-(4-pyridylphenyl)ethylene(4PyTPE)can be easily encapsulated into the hydrophobic layer of SDS micelles through noncovalent interaction,which exhibits aggregation-induced emission(AIE)phenomenon and can be used as energy donor.By using amphoteric sulforhodamine 101(SR101)fluorescent dye attached to the negatively charged surface of SDS micelles through electrostatic interaction as energy acceptor,the light-harvesting FRET process can be efficiently simulated.Through the steady-state emission spectra analysis in the micelle-mediated energy transfer from 4PyTPE to SR101,the fluorescence emission can be tuned and white light emission with CIE coordinates of(0.31,0.29)can be successfully achieved by tuning the donor/acceptor ratio.More importantly,to better mimic natural photosynthesis,the SDS micelles with 4PyTPE and SR101 FRET system showed enhanced catalytic activity in photochemical catalysis for dehalogenation ofα-bromoacetophenone in aqueous solution and the photocatalytic reaction could be extended to gram levels.

Identification of photochemical effects in Ni-based photothermal catalysts

Photochemical catalytic processes can reduce the activation energy so that reactions can occur under milder conditions.However,it is still unknown whether photochemical effects are present in photothermal catalysis over conventional transition metal materials.Herein,the representative photothermal CO_(2)hydrogenation catalyst,Ni@p-SiO_(2),is employed as a model system to quantitatively probe the contribution of photochemical effect.Through a series of catalytic and photophysical characterizations,it is found that negligible photochemical effect in the ultraviolet-visible region can be observed for the traditional Ni-based catalyst.The results of photo-electrochemistry(PEC)test further confirm that no apparent photochemical effect is present for the Ni@p-SiO_(2)catalyst in the aqueous-phase environment.It has been further evidenced that the photochemical contributions can be significantly amplified by introducing plasmonic metals,such as Au,into the system.This work provides a guideline for the design and construction of efficient synergetic photothermal-photochemical catalytic systems.