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1. Reduced Auger Coefficient through Efficient Carrier Capture and Improved Radiative Efficiency from the Broadband Optical Cavity: A Mechanism for Potential Droop Mitigation in InGaN/GaN LEDs

Author:
Tarni Aggarwal; Ankit Udai; Pratim K. Saha; Swaroop Ganguly; Pallab Bhattacharya; Dipankar Saha
Source:
ACS applied materials & interfaces 2022 v.14 no.11 pp. 13812-13819
ISSN:
1944-8252
Subject:
photons,   etc   ; absorption; spectroscopy;     Show all 3 Subjects
Abstract:
... Efficiency droop at high carrier-injection regimes is a matter of concern in InGaN/GaN quantum-confined heterostructure-based light-emitting diodes (LEDs). Processes such as Shockley–Reed–Hall and Auger recombinations, electron–hole wavefunction separation from polarization charges, carrier leakage, and current crowding are identified as the primary contributors to efficiency droop. Auger recombin ...
DOI:
10.1021/acsami.1c20003

2. Defect-Type-Dependent Carrier Lifetimes in Monolayer WS₂ Films

Author:
Yuanshuang Liu; Huan Liu; Jiangcai Wang; Dameng Liu
Source:
Journal of physical chemistry 2022 v.126 no.10 pp. 4929-4938
ISSN:
1932-7455
Subject:
photons,   etc   ; molecular dynamics; photoluminescence;     Show all 3 Subjects
Abstract:
... The band-edge carrier recombination rate determines the internal quantum efficiency of light-emitting diodes (LEDs), which is predominantly determined by the carrier lifetime. Point defects in transition metal dichalcogenides (TMDs) as dominant nonradiative recombinations affect the carrier lifetimes, hindering photon emission. Uncovering the mechanism of different defect types on carrier lifetime ...
DOI:
10.1021/acs.jpcc.1c09603

3. Observation of a High-Energy Tamm Plasmon State in the Near-IR Region

Author:
Oleksandr Buchnev; Alexandr Belosludtsev; Vassili A. Fedotov
Source:
ACS applied materials & interfaces 2022 v.14 no.11 pp. 13638-13644
ISSN:
1944-8252
Subject:
photons,   etc   ; energy; gold; topology;     Show all 4 Subjects
Abstract:
... We report on the experimental observation of a Tamm plasmon state in the near-IR region characterized by an anomalously high energy level located in the upper half of the photonic band gap. Such a “blue” Tamm plasmon was demonstrated at the interface between a conventional, completely periodic Bragg reflector and a nanostructured nonresonant thin gold grating. We study the effect of the grating pe ...
DOI:
10.1021/acsami.2c00486

4. Imbibition-induced Ultrafast Assembly and Printing of Colloidal Photonic Crystals

Author:
Weibin Li; Chen Zhang; Ding Lan; Wenjie Ji; Zhongyu Zheng; Yuren Wang
Source:
Journal of colloid and interface science 2022 pp. -
ISSN:
0021-9797
Subject:
photons,   etc   ; droplets; imbibition; nanopores; solvents;     Show all 5 Subjects
Abstract:
... Hypothesis Self-assembly of colloidal particles enables the versatile fabrication of highly ordered structures and materials for optical, sensing, and other applications. Nevertheless, many traditional assembly processes are inefficient, because there exists an inevitable contradiction between time efficiency and crystalline quality. In this work, we introduce an ultrafast, robust, and scalable ap ...
DOI:
10.1016/j.jcis.2022.05.114

5. Effect of BaTiO₃ powder as an additive in perovskite films on solar cells

Author:
Chuanxiang Zhang; Xiqiang Li; Lingling Ding; Chen Jin; Haijun Tao
Source:
RSC advances 2022 v.12 no.13 pp. 7950-7960
ISSN:
2046-2069
Subject:
photons,   etc   ; barium titanate; electric field; energy;     Show all 4 Subjects
Abstract:
... Perovskite solar cells (PSCs) are considered to be ideal energy devices, where perovskite-type organic metal halides act as light-absorbing materials. In PSCs, the photoexcitons are extracted and separated to afford high photoelectric conversion efficiency under the action of the built-in electric field (Ebᵢ). However, the current challenge is that a low Ebᵢ cannot provide a sufficient driving for ...
DOI:
10.1039/d1ra09374f

6. Merging Charge Transfer into Metal–Organic Frameworks to Achieve High Reduction Potentials via Multiphoton Excitation

Author:
Leixin Hou; Xu Jing; Huilin Huang; Chunying Duan
Source:
ACS applied materials & interfaces 2022 v.14 no.13 pp. 15307-15316
ISSN:
1944-8252
Subject:
photons,   etc   ; absorption; cations; dyes; ligands; photocatalysis;     Show all 6 Subjects
Abstract:
... Utilization of multiphotons to achieve high reduction potentials is a highly demanding but still challenging task for reductive cleavage of inert bonds. Herein, we report a new charge transfer approach that simultaneously excites the electron-rich dye and the radical anionic of the electron-deficient one for photocatalytic activation of aryl chlorides with high reduction potentials (Eᵣₑd ≈ −1.9 to ...
DOI:
10.1021/acsami.2c01595

7. Short Photoluminescence Lifetimes Linked to Crystallite Dimensions, Connectivity, and Perovskite Crystal Phases

Author:
Raquel Chuliá-Jordán; Emilio J. Juarez-Perez
Source:
Journal of physical chemistry 2022 v.126 no.7 pp. 3466-3474
ISSN:
1932-7455
Subject:
photons,   etc   ; crystallites; energy; photoluminescence; physical chemistry;     Show all 5 Subjects
Abstract:
... Time-correlated single photon counting has been conducted to gain further insights into the short photoluminescence lifetimes (nanosecond) of lead iodide perovskite (MAPbI₃) thin films (∼100 nm). We analyze three different morphologies, compact layer, isolated island, and connected large grain films, from 14 to 300 K using a laser excitation power of 370 nJ/cm². Lifetime fittings from the Generali ...
DOI:
10.1021/acs.jpcc.1c08867

8. Tunable Circularly Polarized Luminescence with a High Dissymmetry Factor Emitted from Luminogen-Bonded and Electrically Controlled Polymer-Stabilized Cholesteric Liquid Crystals

Author:
Zhaozhong Li; Ruochen Lan; Jinying Bao; Wei Hu; Meng Wang; Lanying Zhang; Huai Yang
Source:
ACS applied materials & interfaces 2022 v.14 no.6 pp. 8490-8498
ISSN:
1944-8252
Subject:
photons,   etc   ; electric field; fluorescence; liquid crystals;     Show all 4 Subjects
Abstract:
... Circularly polarized luminescence (CPL)-active materials with high dissymmetry factor (gₗᵤₘ) values show great potential in photonic devices. In this study, electric-field-driven systems with tunable CPL signals are successfully fabricated based on polymer-stabilized cholesteric liquid crystal (PSChLC) doping by fluorescent molecules. By constructing a gradient helical superstructure of PSChLCs, d ...
DOI:
10.1021/acsami.1c24264

9. Construction of surface molecularly imprinted photonic hydrogel sensors with high sensitivity

Author:
Zhaokun Yang; Huajun Jin; Ang Yu; Zhangyong Yu; Dongjian Shi; Shengrong Yan; Liyan Qin; Shirong Liu; Mingqing Chen
Source:
Colloids and surfaces 2022 v.639 pp. 128341
ISSN:
0927-7757
Subject:
photons,   etc   ; hydrogels; hydrogen; milk; polymerization; porous media;     Show all 6 Subjects
Abstract:
... In comparison with molecularly imprinted photonic hydrogel (MIPH) with specific molecular recognition sites inside matrix, surface molecularly imprinted photonic hydrogel (S-MIPH) is more competitive as a molecular sensor due to presence of molecular recognition sites distributed on surface of hydrogel wall. Nevertheless, the construction of S-MIPH sensors is still challenging owing to the absence ...
DOI:
10.1016/j.colsurfa.2022.128341

10. Liquid-crystalline ordering of davydov-split aggregates of cyanine dyes

Author:
Yiping Ma; Arianna Dicce; Nitin Ramesh Reddy; Jiyu Fang
Source:
Colloids and surfaces 2022 v.642 pp. 128713
ISSN:
0927-7757
Subject:
photons,   etc   ; ammonia; lipophilicity; methanol; ultraviolet-visible spectroscopy;     Show all 5 Subjects
Abstract:
... 3,3′-ditetradecyloxacarbocyanine (DiOC₁₄(3)) and 3,3′-Dioctadecyloxacarbocyanine (DiOC₁₈(3)) are lipophilic carbocyanine dyes with a conjugated polymethine backbone and two long hydrocarbon tails. In this paper, we report the formation of Davydov-split aggregates of DiOC₁₄(3) and DiOC₁₈(3) in methanol/water mixtures with and without ammonia, which show a blue-shifted H-band and a red-shifted J-ban ...
DOI:
10.1016/j.colsurfa.2022.128713

11. Approaching the Spin-Statistical Limit in Visible-to-Ultraviolet Photon Upconversion

Author:
Axel Olesund; Jessica Johnsson; Fredrik Edhborg; Shima Ghasemi; Kasper Moth-Poulsen; Bo Albinsson
Source:
Journal of the American Chemical Society 2022 v.144 no.8 pp. 3706-3716
ISSN:
1520-5126
Subject:
photons,   etc   ; absorption; energy conversion; fluorescence; naphthalene; solar energy;     Show all 6 Subjects
Abstract:
... Triplet–triplet annihilation photon upconversion (TTA-UC) is a process in which triplet excitons combine to form emissive singlets and holds great promise in biological applications and for improving the spectral match in solar energy conversion. While high TTA-UC quantum yields have been reported for, for example, red-to-green TTA-UC systems, there are only a few examples of visible-to-ultraviole ...
DOI:
10.1021/jacs.1c13222

12. Light-Driven Fabrication of a Chiral Photonic Lattice of the Helical Nanofilament Liquid Crystal Phase

Author:
Wongi Park; Jongmin Lee; Moon Jong Han; Joanna Wolska; Damian Pociecha; Ewa Gorecka; Min-Kyo Seo; Yun-Seok Choi; Dong Ki Yoon
Source:
ACS applied materials & interfaces 2022 v.14 no.3 pp. 4409-4416
ISSN:
1944-8252
Subject:
photons,   etc   ; cost effectiveness; liquid crystals; reflectance; silicon; transmittance;     Show all 6 Subjects
Abstract:
... A photonic lattice is an efficient platform for optically exploring quantum phenomena. However, its fabrication requires high costs and complex procedures when conventional materials, such as silicon or metals, are used. Here, we demonstrate a simple and cost-effective fabrication method for a reconfigurable chiral photonic lattice of the helical nanofilament (HNF) liquid crystal (LC) phase and di ...
DOI:
10.1021/acsami.1c19382

13. State-of-the-art developments in carbon quantum dots (CQDs): Photo-catalysis, bio-imaging, and bio-sensing applications

Author:
Mohammad Ehtisham Khan; Akbar Mohammad; Taeho Yoon
Source:
Chemosphere 2022 v.302 pp. 134815
ISSN:
0045-6535
Subject:
photons,   etc   ; bioimaging; drugs; energy; photocatalysis; photoluminescence; solar energy;     Show all 7 Subjects
Abstract:
... Carbon quantum dots (CQDs), the intensifying nanostructured form of carbon material, have exhibited incredible impetus in several research fields such as bio-imaging, bio-sensing, drug delivery systems, optoelectronics, photovoltaics, and photocatalysis, thanks to their exceptional properties. The CQDs show extensive photonic and electronic properties, as well as their light-collecting, tunable ph ...
DOI:
10.1016/j.chemosphere.2022.134815

14. Upconversion Nanoparticle-Integrated Bilayer Inverse Opal Photonic Crystal Film for the Triple Anticounterfeiting

Author:
Zhipeng Meng; Yue Wu; Jie Ren; Xiyan Li; Shufen Zhang; Suli Wu
Source:
ACS applied materials & interfaces 2022 v.14 no.10 pp. 12562-12570
ISSN:
1944-8252
Subject:
photons,   etc   ; hydrophilicity; luminescence; night vision; opal; solar radiation;     Show all 6 Subjects
Abstract:
... Optical anticounterfeiting plays a vital role in information security because it can be recognized by the naked eye and is difficult to imitate. Herein, a hydrophilic modified upconversion nanoparticle (M-UCNP)-integrated bilayer inverse opal photonic crystal (IOPC) film was designed in which the luminescent M-UCNPs were deposited on the surface of the optimized bilayer structure with double photo ...
DOI:
10.1021/acsami.1c25059

15. Externally tunable multichannel filtering applications of organic material based 1D magnetic cold-plasma photonic crystals

Author:
S. K. Awasthi; Alireza Aghajamali; A. M. Mohamed; Z. S. Matar; A. F. Amin; Arafa H. Aly
Source:
RSC advances 2022 v.12 no.23 pp. 14849-14857
ISSN:
2046-2069
Subject:
photons,   etc   ; computer software; heptane; hexane; magnetic fields; octane; pentane;     Show all 7 Subjects
Abstract:
... In the present research work, we employed the transfer matrix method (TMM) in addition to MATLAB software to examine the transmission properties of various organic-based one-dimensional (1D) magnetic cold-plasma photonic crystals (MCPPhCs). The proposed structures were found to be made up of periodic layers of organic materials and magnetic cold-plasma (MCP) at normal incidence. An external magnet ...
DOI:
10.1039/d2ra01755e

16. Laser-Patterned Submicrometer Bi₂Se₃–WS₂ Pixels with Tunable Circular Polarization at Room Temperature

Author:
Zachariah Hennighausen; Darshana Wickramaratne; Kathleen M. McCreary; Bethany M. Hudak; Todd Brintlinger; Hsun-Jen Chuang; Mehmet A. Noyan; Berend T. Jonker; Rhonda M. Stroud; Olaf M. van ’t Erve
Source:
ACS applied materials & interfaces 2022 v.14 no.7 pp. 9504-9514
ISSN:
1944-8252
Subject:
photons,   etc   ; absorption; ambient temperature; desorption; disulfides; oxygen; photoluminescence; tungsten;     Show all 8 Subjects
Abstract:
... Characterizing and manipulating the circular polarization of light is central to numerous emerging technologies, including spintronics and quantum computing. Separately, monolayer tungsten disulfide (WS₂) is a versatile material that has demonstrated promise in a variety of applications, including single photon emitters and valleytronics. Here, we demonstrate a method to tune the photoluminescence ...
DOI:
10.1021/acsami.1c24205

17. Organic–Inorganic Hybrid Cuprous Halide Scintillators for Flexible X-ray Imaging

Author:
Peng Mao; Yongan Tang; Bohan Wang; Dianyuan Fan; Yu Wang
Source:
ACS applied materials & interfaces 2022 v.14 no.19 pp. 22295-22301
ISSN:
1944-8252
Subject:
photons,   etc   ; X-radiation; crystal structure; detection limit; photoluminescence; radiography;     Show all 6 Subjects
Abstract:
... Recently, organic-inorganic hybrid scintillators have received more and more attention because of their merits of easy preparation, good stability, and nontoxicity. Considering the high cost of traditional inorganic scintillators, here we describe experimental investigations of a low-cost zero-dimensional scintillator comprising organic-inorganic hybrid cuprous halide and its capabilities for sens ...
DOI:
10.1021/acsami.2c02660

18. Photonic Cellulose Films with Vivid Structural Colors: Fabrication and Selectively Chemical Response

Author:
Zi-li Wang; Qiang Wang; Xiu Dong; Dong Li; Lan Bai; Xiu-li Wang; Yu-zhong Wang; Fei Song
Source:
Biomacromolecules 2022 v.23 no.4 pp. 1662-1671
ISSN:
1526-4602
Subject:
photons,   etc   ; absorption; cellulose; color; light intensity; nanocrystals; polymers; solubility;     Show all 8 Subjects
Abstract:
... Recent advances in structural-color cellulose nanocrystal (CNC) materials have been made toward chemical sensing applications; however, such materials lack sufficient color chroma for naked-eye observation, and their selective recognition to given chemicals as well as the corresponding mechanism has rarely been reported. Here, a dopamine-infiltration and post-polymerization approach is proposed to ...
DOI:
10.1021/acs.biomac.1c01567

19. Cephalopod-Mimetic Tunable Photonic Coatings Assembled from Quasi-Monodispersed Reflectin Protein Nanoparticles

Author:
Jun Jie Loke; Shawn Hoon; Ali Miserez
Source:
ACS applied materials & interfaces 2022 v.14 no.18 pp. 21436-21452
ISSN:
1944-8252
Subject:
photons,   etc   ; Cephalopoda; camouflage; chemistry; chromatophores; color; ligands; particle size; squid;     Show all 9 Subjects
Abstract:
... The remarkable dynamic camouflage ability of cephalopods arises from precisely orchestrated structural changes within their chromatophores and iridophores photonic cells. This mesmerizing color display remains unmatched in synthetic coatings and is regulated by swelling/deswelling of reflectin protein nanoparticles, which alters platelet dimensions in iridophores to control photonic patterns accor ...
DOI:
10.1021/acsami.2c01999

20. Highly Ordered, Plasmonic Enhanced Inverse Opal Photonic Crystal for Ultrasensitive Detection of Staphylococcal Enterotoxin B

Author:
Huijing Shen; Jialei Bai; Xudong Zhao; Beibei Lu; Dianpeng Han; Shuang Li; Kang Qin; Shuyue Ren; Yu Wang; Minglin Wang; Yujing Lian; Zhixian Gao; Yuan Peng
Source:
ACS applied materials & interfaces 2022 v.14 no.3 pp. 4637-4646
ISSN:
1944-8252
Subject:
photons,   etc   ; biosensors; detection limit; enterotoxins; liquids; nanogold; oligonucleotides; opal; toxicity;     Show all 9 Subjects
Abstract:
... Although there is considerable interest in self-assembly of ordered, porous “inverse opal” structures for optical, electronic, and chemical applications, uncontrolled defect formation limits the usefulness of such materials. Herein, we develop a highly ordered and plasmonic enhanced sensing inverse opal photonic crystal (IOPC) material. The co-assembly of the colloidal template with the matrix mat ...
DOI:
10.1021/acsami.1c18386