TY  - JOUR
A1  - Xu, Jingsan
A1  - Brenner, Thomas J. K.
A1  - Chen, Zupeng
A1  - Neher, Dieter
A1  - Antonietti, Markus
A1  - Shalom, Menny
T1  - Upconversion-agent induced improvement of g-C3N4 photocatalyst under visible light
JF  - ACS applied materials & interfaces
N2  - Herein, we report the use of upconversion agents to modify graphite carbon nitride (g-C3N4) by direct thermal condensation of a mixture of ErCl3 center dot 6H(2)O and the supramolecular precursor cyanuric acid-melamine. We show the enhancement of g-C3N4 photoactivity after Er3+ doping by monitoring the photodegradation of Rhodamine B dye under visible light. The contribution of the upconversion agent is demonstrated by measurements using only a red laser. The Er3+ doping alters both the electronic and the chemical properties of g-C3N4. The Er3+ doping reduces emission intensity and lifetime, indicating the formation of new, nonradiative deactivation pathways, probably involving charge-transfer processes.
KW  - metal-free photocatalysis
KW  - upconversion
KW  - carbon nitride
KW  - RhB photodegradation
Y1  - 2014
U6  - https://doi.org/10.1021/am5051263
SN  - 1944-8244
VL  - 6
IS  - 19
SP  - 16481
EP  - 16486
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Foertig, Alexander
A1  - Kniepert, Juliane
A1  - Gluecker, Markus
A1  - Brenner, Thomas J. K.
A1  - Dyakonov, Vladimir
A1  - Neher, Dieter
A1  - Deibel, Carsten
T1  - Nongeminate and geminate recombination in PTB7: PCBM solar cells
JF  - Advanced functional materials
KW  - organic semiconductors
KW  - organic solar cells
KW  - conjugated polymers
KW  - charge carrier recombination
Y1  - 2014
U6  - https://doi.org/10.1002/adfm.201302134
SN  - 1616-301X
SN  - 1616-3028
VL  - 24
IS  - 9
SP  - 1306
EP  - 1311
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Xu, Jingsan
A1  - Brenner, Thomas J. K.
A1  - Chabanne, Laurent
A1  - Neher, Dieter
A1  - Antonietti, Markus
A1  - Shalom, Menny
T1  - Liquid-Based growth of polymeric carbon nitride layers and their use in a mesostructured polymer solar cell with V-oc exceeding 1 V
JF  - Journal of the American Chemical Society
N2  - Herein we report a general liquid-mediated pathway for the growth of continuous polymeric carbon nitride (C3N4) thin films. The deposition method consists of the use of supramolecular complexes that transform to the liquid state before direct thermal condensation into C3N4 solid films. The resulting films exhibit continuous porous C3N4 networks on various substrates. Moreover, the optical absorption can be easily tuned to cover the solar spectrum by the insertion of an additional molecule into the starting complex. The strength of the deposition method is demonstrated by the use of the C3N4 layer as the electron acceptor in a polymer solar cell that exhibits a remarkable open-circuit voltage exceeding 1 V. The easy, safe, and direct synthesis of carbon nitride in a continuous layered architecture on different functional substrates opens new possibilities for the fabrication of many energy-related devices.
Y1  - 2014
U6  - https://doi.org/10.1021/ja508329c
SN  - 0002-7863
VL  - 136
IS  - 39
SP  - 13486
EP  - 13489
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Chu, X. -L.
A1  - Brenner, Thomas J. K.
A1  - Chen, X. -W.
A1  - Ghosh, Y.
A1  - Hollingsworth, J. A.
A1  - Sandoghdar, Vahid
A1  - Goetzinger, S.
T1  - Experimental realization of an optical antenna designed for collecting 99% of photons from a quantum emitter
JF  - Optica
N2  - A light source that emits single photons at well-defined times and into a well-defined mode would be a decisive asset for quantum information processing, quantum metrology, and sub-shot-noise detection of absorption. One of the central challenges in the realization of such a deterministic device based on a single quantum emitter concerns the collection of the photons, which are radiated into a 4 pi solid angle. Here, we present the fabrication and characterization of an optical antenna designed to convert the dipolar radiation of an arbitrarily oriented quantum emitter to a directional beam with more than 99% efficiency. Our approach is extremely versatile and can be used for more efficient detection of nanoscopic emitters ranging from semiconductor quantum dots to dye molecules, color centers, or rare-earth ions in various environments. Having addressed the issue of collection efficiency, we also discuss the photophysical limitations of the existing quantum emitters for the realization of a deterministic single-photon source. (C) 2014 Optical Society of America
Y1  - 2014
U6  - https://doi.org/10.1364/OPTICA.1.000203
SN  - 2334-2536
VL  - 1
IS  - 4
SP  - 203
EP  - 208
PB  - Optical Society of America
CY  - Washington
ER  -