@article{deng_francis_weare_castellano_2015, title={Photochemical upconversion and triplet annihilation limit from a boron dipyrromethene emitter}, volume={14}, ISSN={["1474-9092"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84934293936&partnerID=MN8TOARS}, DOI={10.1039/c5pp00106d}, abstractNote={Non-coherent sensitized red-to-green upconversion has been achieved utilizing platinum(II) tetraphenyltetrabenzoporphyrin (PtTPTBP) as the triplet sensitizer and a nearly quantitatively fluorescent meso -(2,6-dichloropyridyl)-substituted boron dipyrromethene (Cl2PyBODIPY) chromophore ( Φ = 0.99 in toluene) as the energy acceptor/annihilator in deoxygenated toluene. Dynamic Stern–Volmer analysis revealed that PtTPTBP phosphorescence as quenched by C_l2PyBODIPY occurs with a K _SV of 108 000 M−1, yielding a triplet–triplet energy transfer rate constant of 2.3 × 109 M−1 s−1. Using a non-coherent red light-emitting diode excitation source centered at 626 nm, the incident power dependence responsible for generating singlet BODIPY fluorescence in the green was shown to traverse quadratic to linear regimes, the latter being achieved near 60 mW cm−2. These data were consistent with a photochemical upconversion mechanism being responsible for generating singlet fluorescence from the C_l2PyBODIPY chromophores through sensitized triplet–triplet annihilation (TTA). Integrated delayed fluorescence transients were utilized to reveal the TTA efficiency for the C_l2PyBODIPY chromophore and saturated near 46%, representing the lower limit for the TTA process. Kinetic modelling of the delayed fluorescence transient produced from 1.5 mJ laser pulses (λ_ex = 615 nm) revealed a maximum limiting TTA efficiency of 64% for this upconverting composition, implying that this is indeed an extremely relevant acceptor/annihilator composition for photochemical upconversion.}, number={7}, journal={PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES}, author={Deng, F. and Francis, A. J. and Weare, W. W. and Castellano, F. N.}, year={2015}, pages={1265–1270} }
 @article{deng_lazorski_castellano_2015, title={Photon upconversion sensitized by a Ru(II)-pyrenyl chromophore}, volume={373}, number={2044}, journal={Philosophical Transactions. Mathematical, Physical, and Engineering Sciences.}, author={Deng, F. and Lazorski, M. S. and Castellano, F. N.}, year={2015} }
 @article{kim_deng_castellano_kim_2014, title={Red-to-Blue/Cyan/Green Upconverting Microcapsules for Aqueous- and Dry-Phase Color Tuning and Magnetic Sorting}, volume={1}, ISSN={["2330-4022"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84906701246&partnerID=MN8TOARS}, DOI={10.1021/ph500036m}, abstractNote={Microcapsules that achieve multicolor triplet–triplet annihilation (TTA)-based upconversion (UC) in both aqueous and dry phases without deoxygenation are presented for the first time. Platinum(II) tetraphenyltetrabenzoporphyrin (PtTPBP) was used as a sensitizer and perylene, 9,10-bis(phenylethynyl)anthracene (BPEA), and a boron dipyrromethene derivative (BD-2) were employed as acceptors for red to blue, cyan, and green UC, respectively. Additional color tuning was introduced into microcapsules by embedding rose bengal onto the microcapsule shell, resulting in UC-mediated excitation of a distal fluorophore through a trivial process. Microcapsules were further modified to host superparamagnetic nanoparticles for magnetic-induced collection, which permitted sorting and color separation potentially instrumental for various photonics-based applications.}, number={4}, journal={ACS PHOTONICS}, author={Kim, Jae-Hyuk and Deng, Fan and Castellano, Felix N. and Kim, Jae-Hong}, year={2014}, month={Apr}, pages={382–388} }