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1.
Dual Functioning Thieno‐Pyrrole Fused BODIPY Dyes for NIR Optical Imaging and Photodynamic Therapy: Singlet Oxygen Generation without Heavy Halogen Atom Assistance 下载免费PDF全文
Dr. Ryan L. Watley Dr. Samuel G. Awuah Dr. Moses Bio Robert Cantu Habtom B. Gobeze Dr. Vladimir N. Nesterov Dr. Sushanta K. Das Prof. Dr. Francis D'Souza Prof. Dr. Youngjae You 《化学:亚洲杂志》2015,10(6):1335-1343
We discovered a rare phenomenon wherein a thieno‐pyrrole fused BODIPY dye (SBDPiR690) generates singlet oxygen without heavy halogen atom substituents. SBDPiR690 generates both singlet oxygen and fluorescence. To our knowledge, this is the first example of such a finding. To establish a structure–photophysical property relationship, we prepared SBDPiR analogs with electron‐withdrawing groups at the para‐position of the phenyl groups. The electron‐withdrawing groups increased the HOMO–LUMO energy gap and singlet oxygen generation. Among the analogs, SBDPiR688, a CF3 analog, had an excellent dual functionality of brightness (82290 m ?1 cm?1) and phototoxic power (99170 m ?1 cm?1) comparable to those of Pc 4, due to a high extinction coefficient (211 000 m ?1 cm?1) and balanced decay (Φflu=0.39 and ΦΔ=0.47). The dual functionality of the lead compound SBDPiR690 was successfully applied to preclinical optical imaging and for PDT to effectively control a subcutaneous tumor. 相似文献
2.
Back Cover: Ultrafast Photoinduced Charge Separation in Wide‐Band‐Capturing Self‐Assembled Supramolecular Bis(donor styryl)BODIPY–Fullerene Conjugates (Chem. Eur. J. 45/2015) 下载免费PDF全文
3.
Dr. Dafeng Yan Dr. Chalachew Mebrahtu Prof. Shuangyin Wang Prof. Dr. Regina Palkovits 《Angewandte Chemie (International ed. in English)》2023,62(16):e202214333
Renewable H2 production by water electrolysis has attracted much attention due to its numerous advantages. However, the energy consumption of conventional water electrolysis is high and mainly driven by the kinetically inert anodic oxygen evolution reaction. An alternative approach is the coupling of different half-cell reactions and the use of redox mediators. In this review, we, therefore, summarize the latest findings on innovative electrochemical strategies for H2 production. First, we address redox mediators utilized in water splitting, including soluble and insoluble species, and the corresponding cell concepts. Second, we discuss alternative anodic reactions involving organic and inorganic chemical transformations. Then, electrochemical H2 production at both the cathode and anode, or even H2 production together with electricity generation, is presented. Finally, the remaining challenges and prospects for the future development of this research field are highlighted. 相似文献
4.
Shabram Sadeghi Esfahlani Hassan Shirvani Sunny Nwaubani Ayoub Shirvani Habtom Mebrahtu 《力学快报》2013,3(3):031002
Structural optimization for crashworthiness criteria is of particular significance especially at early stage of design. The comparative study of Kriging and radial basis function network (RBFN) was performed in order to improve the crashworthiness effects of honeycomb. Improving the crashworthiness characteristic of honeycomb was achieved using LS-OPT® and domain reduction strategy. This optimization is performed on the basis of validated numerical simulation to establish the approximated model to illustrate the relationship between the responses and design variables. The results showed that Kriging meta-model is excelled in accuracy, robustness and efficiency compared to radial basis function (RBF) and crashworthiness characteristic of honeycomb is improved by 4%. 相似文献
5.
Back Cover: Dual Functioning Thieno‐Pyrrole Fused BODIPY Dyes for NIR Optical Imaging and Photodynamic Therapy: Singlet Oxygen Generation without Heavy Halogen Atom Assistance (Chem. Asian J. 6/2015) 下载免费PDF全文
6.
A simple and efficient tetrahydropyranylation of alcohols and phenols has been developed using NaHSO4-SiO2 (0.5 mol%) as a catalyst under solvent-free conditions to yield corresponding tetrahydropyranyl ethers in excellent yields. 相似文献
7.
Ultrafast Photoinduced Charge Separation in Wide‐Band‐Capturing Self‐Assembled Supramolecular Bis(donor styryl)BODIPY–Fullerene Conjugates 下载免费PDF全文
Shuai Shao Habtom B. Gobeze Prof. Dr. Paul A. Karr Prof. Dr. Francis D'Souza 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(45):16005-16016
A new series of self‐assembled supramolecular donor–acceptor conjugates capable of wide‐band capture, and exhibiting photoinduced charge separation have been designed, synthesized and characterized using various techniques as artificial photosynthetic mimics. The donor host systems comprise of a 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) containing a crown ether entity at the meso‐position and two styryl entities on the pyrrole rings. The styryl end groups also carried additional donor (triphenylamine or phenothiazine) entities. The acceptor host system was a fulleropyrrolidine comprised of an ethylammonium cation. Owing to the presence of extended conjugation and multiple chromophore entities, the BODIPY host revealed absorbance and emission well into the near‐IR region covering the 300–850 nm spectral range. The donor–acceptor conjugates formed by crown ether–alkyl ammonium cation binding of the host–guest system was characterized by optical absorbance and emission, computational, and electrochemical techniques. Experimentally determined binding constants were in the range of 1–2×105 M ?1. An energy‐level diagram to visualize different photochemical events was established using redox, computational, absorbance, and emission data. Spectral evidence for the occurrence of photoinduced charge separation in these conjugates was established from femtosecond transient absorption studies. The measured rates indicated ultrafast charge separation and relatively slow charge recombination revealing their usefulness in light‐energy harvesting and optoelectronic device applications. The bis(donor styryl)BODIPY‐derived conjugates populated their triplet excited states during charge recombination. 相似文献
8.
Ruben Canton‐Vitoria Habtom B. Gobeze Vicente M. Blas‐Ferrando Javier Ortiz Youngwoo Jang Fernando Fernndez‐Lzaro ngela Sastre‐Santos Yusuke Nakanishi Hisanori Shinohara Francis D'Souza Nikos Tagmatarchis 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(17):5768-5773
The functionalization of MoS2 is of paramount importance for tailoring its properties towards optoelectronic applications and unlocking its full potential. Zinc phthalocyanine (ZnPc) carrying an 1,2‐dithiolane oxide linker was used to functionalize MoS2 at defect sites located at the edges. The structure of ZnPc‐MoS2 was fully assessed by complementary spectroscopic, thermal, and microscopy imaging techniques. An energy‐level diagram visualizing different photochemical events in ZnPc‐MoS2 was established and revealed a bidirectional electron transfer leading to a charge separated state ZnPc. + ‐MoS2.?. Markedly, evidence of the charge transfer in the hybrid material was demonstrated using fluorescence spectroelectrochemistry. Systematic studies performed by femtosecond transient absorption revealed the involvement of excitons generated in MoS2 in promoting the charge transfer, while the transfer was also possible when ZnPc was excited, signifying their potential in light‐energy‐harvesting devices. 相似文献
9.
Panchromatic Light Capture and Efficient Excitation Transfer Leading to Near‐IR Emission of BODIPY Oligomers 下载免费PDF全文
Ritambhara Sharma Habtom B. Gobeze Prof. Dr. Francis D'Souza Prof. Dr. Mangalampalli Ravikanth 《Chemphyschem》2016,17(16):2516-2524
All‐BODIPY‐based (BODIPY=boron‐dipyrromethene) donor–acceptor systems capable of wide‐band absorbance leading to efficient energy transfer in the near‐IR region are reported. A covalently linked 3‐pyrrolyl BODIPY–BODIPY dimer building block bearing an ethynyl group at the meso‐aryl position is synthesized and coupled with three different monomeric BODIPY/pyrrolyl BODIPY building blocks with a bromo/iodo group under Pd0 coupling conditions to obtain three covalently linked 3‐pyrrolyl‐BODIPY‐based donor–acceptor oligomers in 19–29 % yield. The oligomers are characterized in detail by 1D and 2D NMR spectroscopy, high‐resolution mass spectrometry, and optical spectroscopy. Due to the presence of different functionalized BODIPY derivatives in the oligomers, panchromatic light capture (300–725 nm) is witnessed. Fluorescence studies reveal singlet–singlet energy transfer from BODIPY monomer to BODIPY dimer leading to emission in the 700–800 nm range. Theoretical modeling according to the Förster mechanism predicts ultrafast energy transfer due to good spectral overlap of the donor and acceptor entities. Femtosecond transient absorption studies confirm this to be the case and thus show the relevance of the currently developed all‐BODIPY‐based energy‐funneling supramolecular sytems with near‐IR emission to solar‐energy harvesting applications. 相似文献
10.
Dr. Luis M. Arellano Dr. Habtom B. Gobeze Youngwoo Jang Dr. Myriam Barrejón Dr. Concepción Parejo Dr. Julio C. Álvarez Dr. María J. Gómez-Escalonilla Prof. Ángela Sastre-Santos Prof. Francis D'Souza Prof. Fernando Langa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(22):e202200254
Graphene doped with heteroatoms such as nitrogen, boron, and phosphorous by replacing some of the skeletal carbon atoms is emerging as an important class of two-dimensional materials as it offers the much-needed bandgap for optoelectronic applications and provides better access for chemical functionalization at the heteroatom sites. Covalent grafting of photosensitizers onto such doped graphenes makes them extremely useful for light-induced applications. Herein, we report the covalent functionalization of N-doped graphene (NG) with two well-known electron donor photosensitizers, namely, zinc porphyrin (ZnP) and zinc phthalocyanine (ZnPc), using the simple click chemistry approach. Covalent attachment of ZnP and ZnPc at the N-sites of NG in NG−ZnP and NG−ZnPc hybrids was confirmed by using a range of spectroscopic, thermogravimetric and imaging techniques. Ground- and excited-state interactions in NG−ZnP and NG−ZnPc were monitored by using spectral and electrochemical techniques. Efficient quenching of photosensitizer fluorescence in these hybrids was observed, and the relatively easier oxidations of ZnP and ZnPc supported excited-state charge-separation events. Photoinduced charge separation in NG−ZnP and NG−ZnPc hybrids was confirmed by using the ultrafast pump-probe technique. The measured rate constants were of the order of 1010 s,−1 thus indicating ultrafast electron transfer phenomena. 相似文献