Article
Chemistry, Multidisciplinary
Stefan W. Tabernig, Lin Yuan, Andrea Cordaro, Zhi Li Teh, Yijun Gao, Robert J. Patterson, Andreas Pusch, Shujuan Huang, Albert Polman
Summary: We have designed an optically resonant bulk heterojunction solar cell to study the optoelectronic properties of nanostructured p-n junctions. By optimizing the nanoscale pattern, we were able to improve the efficiency of the solar cell by enhancing the absorption and charge-carrier extraction behavior. Our experiments and simulations showed significant improvement in infrared response and current gain in the patterned solar cell compared to the planar reference, demonstrating the importance of nanostructured geometries in enhancing solar cell performance.
Article
Chemistry, Physical
Hyemin Jo, Jai Kyeong Kim, Junghwan Kim, Tae-Yeon Seong, Hae Jung Son, Jeung-Hyun Jeong, Hyeonggeun Yu
Summary: By using atomic layer deposition (ALD) of ZnO buffer at a low temperature, the interfacial band alignment can be enhanced, resulting in an increased photocurrent density above 35 mA/cm(2) at the band gap of PbS quantum dots of 1.18 eV. The electron barrier with ALD-ZnO is 0.55 eV lower compared to sol-gel ZnO, and the photoactivation of shallow gap states in ALD-ZnO induces band bending for efficient electron tunneling from PbS to ZnO, leading to improved device lifetime under constant illumination at 1-sun.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
David Becker-Koch, Miguel Albaladejo-Siguan, Yvonne J. Hofstetter, Olga Solomeshch, Darius Pohl, Bernd Rellinghaus, Nir Tessler, Yana Vaynzof
Summary: Efficiency of PbS quantum dot solar cells has increased, with potential for industrial applications. The use of organic layers like PTAA can improve efficiency while avoiding stability issues associated with EDT and MoO3 layers.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Bin Bin Jin, Shu Ying Kong, Guo Qing Zhang, Xing Qiao Chen, Hong Shan Ni, Fan Zhang, Dan Jun Wang, Jing Hui Zeng
Summary: The study focuses on inhibiting interfacial charge recombination in CdSe QDSSCs by constructing a ZnS/QDs/ZnS double-layer barrier structure and applying an electric field in VASILAR, achieving higher efficiency.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Chemistry, Physical
Miguel Albaladejo-Siguan, David Becker-Koch, Elizabeth C. Baird, Yvonne J. Hofstetter, Ben P. Carwithen, Anton Kirch, Sebastian Reineke, Artem A. Bakulin, Fabian Paulus, Yana Vaynzof
Summary: Light-harvesting devices made from lead sulfide quantum dot absorbers have promising applications in third-generation photovoltaics. Passivating the quantum dot surfaces and managing the excess lead halide can improve device performance and stability.
ADVANCED ENERGY MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Nataliia Sukharevska, Dmytro Bederak, Vincent M. Goossens, Jamo Momand, Herman Duim, Dmitry N. Dirin, Maksym Kovalenko, Bart J. Kooi, Maria A. Loi
Summary: The recent advancement in phase transfer ligand exchange methods has improved the performance of PbS quantum dots solar cells and simplified film deposition complexity. By using highly stable PbS QD inks, efficient solar cells have been successfully fabricated.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Qiangqiang Wang, Xuanyu Zhang, Lei Qian, Chaoyu Xiang
Summary: Perovskite quantum dot light-emitting diodes (QLEDs) have potential for next-generation displays. The electron-accepting property of poly-[bis-(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA) leads to the charging of quantum dot (QD) films, resulting in imbalance of charge injection and increased nonradiative recombination, affecting the QLEDs performance. This study compared two polymers, poly-(methyl methacrylate) (PMMA) and poly-(vinylpyrrolidone) (PVP), as hole interface buffer layers for QD films. The devices with PMMA achieved a maximum external quantum efficiency of 20.71%.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Xing Meng, Yifan Chen, Fan Yang, Jieqi Zhang, Guozheng Shi, Yannan Zhang, Haodong Tang, Wei Chen, Yang Liu, Lin Yuan, Shaojuan Li, Kai Wang, Qi Chen, Zeke Liu, Wanli Ma
Summary: This study explores the potential of using conjugated polymers as hole-transporting layer (HTL) in lead sulfide (PbS) quantum dot solar cells. The precise regulation of the inorganic/organic interface is crucial for achieving high-performance devices. By introducing CsPbl(3) quantum dots as an interfacial layer between the PbS quantum dot active layer and the organic polymer HTL, the interface is mediated and favorable energy level alignment is achieved, resulting in improved charge extraction and reduced interfacial charge recombination. As a result, the photovoltaic performance is efficiently improved from 10.50% to 12.32%. This study may provide new guidelines for the device structural design of quantum dot optoelectronics by integrating different solution-processed semiconductors.
Article
Energy & Fuels
Meiying Li, Shuaipu Zang, Yinglin Wang, Jinhuan Li, Jiangang Ma, Xintong Zhang, Yichun Liu
Summary: This study successfully improved the power conversion efficiency of PbS colloidal quantum dot solar cells by preparing a n(+)−n double-layered ZnO electron transport layer.
Article
Physics, Applied
Xi-Kai Yang, Jia-Wei Qiao, Zhi-Hao Chen, Zhen-Chuan Wen, Hang Yin, Xiao-Tao Hao
Summary: By incorporating CdSe quantum dots as a third component, this study has successfully enhanced the current density and power conversion efficiency of organic solar cells. CdSe QDs modulate charge dynamics, increase fluorescence external quantum efficiency, and enable Forster resonance energy transfer and fast charge transfer in BHJ films, resulting in improved overall device performance.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Mingyu Li, Shiwu Chen, Xinzhao Zhao, Kao Xiong, Bo Wang, Usman Ali Shah, Liang Gao, Xinzheng Lan, Jianbing Zhang, Hsien-Yi Hsu, Jiang Tang, Haisheng Song
Summary: Infrared solar cells incorporating PbS colloidal quantum dots show high efficiency and stability under full-spectrum illumination, with novel energy-level aligned ZnO thin film and hybrid ligand passivation strategies boosting the performance. The development of matched charge extraction and QD passivation approaches is expected to advance QD optoelectronics technology.
Article
Chemistry, Physical
Chao Ding, Dandan Wang, Dong Liu, Hua Li, Yusheng Li, Shuzi Hayase, Tomah Sogabe, Taizo Masuda, Yong Zhou, Yingfang Yao, Zhigang Zou, Ruixiang Wang, Qing Shen
Summary: Lead sulfide colloidal quantum dot solar cells face challenges of non-radiative recombination and electron-hole extraction imbalance due to defects in the three interfaces. Coordinated control and passivation of these interfaces in PbS CQDSCs can improve charge transport, carrier extraction balance, and reduce non-radiative recombination.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Ciyu Ge, Erqi Yang, Xinzhao Zhao, Can Yuan, Sen Li, Chong Dong, Yingfeng Ruan, Liuchong Fu, Yuming He, XiangBin Zeng, Haisheng Song, Bin Hu, Chao Chen, Jiang Tang
Summary: This study proposes a simple method to fabricate window materials for infrared solar cells using hydrogen-doped indium oxide films prepared by room temperature magnetron sputtering. The low-temperature annealed conductive electrodes exhibit high mobility and infrared transmittance, improving the performance of the solar cells.
Article
Chemistry, Multidisciplinary
Yunxiang Di, Kun Ba, Yan Chen, Xudong Wang, Mingqing Zhang, Xinning Huang, Yi Long, Mengdi Liu, Shukui Zhang, Weiyi Tang, Zhangcheng Huang, Tie Lin, Hong Shen, Xiangjian Meng, Meikang Han, Qi Liu, Jianlu Wang
Summary: A two-dimensional titanium carbide (Ti3C2Tx) MXene film is introduced as an effective transparent conducting electrode in lead sulfide quantum dot photodiodes. Exhibiting exceptional near-infrared transmittance control, interface engineering enhances performance, yielding high detectivity, extensive dynamic response, and notable bandwidth, thereby advancing infrared photodiode technology.
Article
Energy & Fuels
Narges Torabi, Elisa Artegiani, Andrea Gasparotto, Fabio Piccinelli, Matteo Meneghini, Gaudenzio Meneghesso, Alessandro Romeo
Summary: This study applies CdSe as a buffer layer on thermally evaporated Sb2Se3-based solar cells, comparing it with the CdS/Sb2Se3 junction. The results show that CdSe improves the external quantum efficiency, increasing the average current density of the devices. The fill factor is also improved, but the open circuit voltage slightly decreases. Additionally, CdSe/Sb2Se3 samples demonstrate excellent stability under accelerated stability tests.
Article
Chemistry, Multidisciplinary
Henry J. Shulevitz, Tzu-Yung Huang, Jun Xu, Steven J. Neuhaus, Raj N. Patel, Yun Chang Choi, Lee C. Bassett, Cherie R. Kagan
Summary: In this study, a scalable strategy using capillary-driven, template-assisted self-assembly is presented to form ordered arrays of nanodiamonds. Measurements of over 200 nanodiamonds reveal a statistical understanding of their structural, optical, and quantum properties.
Review
Chemistry, Multidisciplinary
Yi-Yu Cai, Yun Chang Choi, Cherie R. Kagan
Summary: Colloidal noble metal nanoparticles can be assembled into different forms of artificial metamolecules and materials with tunable optical properties, allowing manipulation of light transmission and reflection.
ADVANCED MATERIALS
(2023)
Review
Chemistry, Physical
Rito Yanagi, Tianshuo Zhao, Devan Solanki, Zhenhua Pan, Shu Hu
Summary: The study discusses the limitations of photocatalysts in terms of quantum yield and inefficient separation of photogenerated charge carriers. Three types of charge-separation modes are identified based on their driving forces, and strategies for improving charge separation in photocatalysts are elucidated and compared. The framework and discussions aim to provide guidance for pursuing efficient photocatalysts.
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Emanuele Marino, Harshit Bharti, Jun Xu, Cherie R. Kagan, Christopher B. Murray
Summary: In this work, we fabricate tunable optical microresonators using semiconductor nanocrystals. By changing the surface chemistry and initiating photo-oxidation of the nanocrystals, we are able to effectively tune the cavity length and refractive index of the microresonator. This study provides a new approach for constructing optical circuits.
Article
Chemistry, Multidisciplinary
Austin W. Keller, Emanuele Marino, Di An, Steven J. Neuhaus, Katherine C. Elbert, Christopher B. Murray, Cherie R. Kagan
Summary: Patterning materials with nanoscale features opens up various research opportunities. This study demonstrates the use of colloidal lithography to transfer an anisotropic pattern of discrete features onto substrates with critical dimensions below 5 nm.
Article
Multidisciplinary Sciences
Dahin Kim, Dennis Ndaya, Reuben Bosire, Francis K. Masese, Weixingyue Li, Sarah M. Thompson, Cherie R. Kagan, Christopher B. Murray, Rajeswari M. Kasi, Chinedum O. Osuji
Summary: Liquid crystals (LCs) are promising materials for the fabrication of reconfigurable arrays of 2D nanomaterials. However, achieving stable dispersions of nanomaterials in LCs is challenging. In this study, good dispersions of pristine CdSe nanoplatelets (NPLs) in LCs were achieved, and their alignment and associated photoluminescence could be controlled by a magnetic field. The dispersion stability was greatly enhanced using polymeric LCs, and the stability was higher in the smectic phases compared to the nematic phases. The aligned composites exhibited highly polarized emission that could be manipulated by field-realignment, which can have applications in programmable materials for photonics.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Tianshuo Zhao, Qinghua Zhao, Jaeyoung Lee, Shengsong Yang, Han Wang, Ming-Yuan Chuang, Yulian He, Sarah M. Thompson, Guannan Liu, Nuri Oh, Christopher B. Murray, Cherie R. Kagan
Summary: In this study, tetrahedral InP QDs with approximately 8 nm edge length were synthesized and used to investigate charge transport in thin films via the FET platform. A hybrid ligand-exchange strategy was designed to enhance interdot coupling and control n-doping of InP QD films, leading to significant improvements in electron mobility and on-off current ratio in FET devices. Surface modification with thin Se overlayers resulted in lower trap-state densities and longer carrier lifetimes, increasing carrier diffusion length by four times.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Uri R. Gabinet, Changyeon Lee, Na Kyung Kim, Martin Hulman, Sarah M. Thompson, Cherie R. Kagan, Chinedum O. Osuji
Summary: Molybdenum disulfide nanosheets exhibit anisotropic optical and electronic properties, and their orientation can be controlled to uncover and utilize these properties.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Polymer Science
Shawn M. Maguire, John Derek Demaree, Michael J. Boyle, Austin W. Keller, Connor R. Bilchak, Cherie R. Kagan, Christopher B. Murray, Kohji Ohno, Russell J. Composto
Summary: We demonstrate the segregation of polymer-grafted nanoparticles to the free surface of a film upon thermal annealing, driven by the lower surface energy of the grafted polymer. By using various microscopy and spectroscopy techniques, we observe the evolution of surface excess of poly(methyl methacrylate)-grafted silica nanoparticles in films as a function of annealing time. The growth of the surface excess is determined by entropic contributions, surface energy differences, and the Flory-Huggins interaction parameter. This study provides insights for designing polymer nanocomposite films with desirable surface properties and highlights the need for rigorous models to capture complex phase behaviors.
Article
Nanoscience & Nanotechnology
Hao A. Nguyen, David Sharp, Johannes E. Froch, Yi-Yu Cai, Shenwei Wu, Madison Monahan, Christopher Munley, Arnab Manna, Arka Majumdar, Cherie R. Kagan, Brandi M. Cossairt
Summary: This work demonstrates a method to achieve scalable deterministic positioning of stable single quantum dots (QDs) by exploiting QD size and utilizing template-assisted self-assembly. By encapsulating CdSe/CdS core/shell QDs in silica, their physical size and photostability are increased. The QDs are then precisely positioned into ordered arrays with a high yield. The resulting QDs exhibit antibunching behavior and retain their optical properties over an extended period of time.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Sebastian Hurtado Parra, Daniel B. Straus, Bryan T. Fichera, Natasha Iotov, Cherie R. Kagan, James M. Kikkawa
Summary: In this study, evidence for the formation and relaxation of large exciton polarons in 2D organic-inorganic hybrid perovskites was found. It was demonstrated that the structural differences among materials strongly influenced the exciton polaron relaxation process.
Article
Chemistry, Multidisciplinary
Steven J. Neuhaus, Emanuele Marino, Christopher B. Murray, Cherie R. . Kagan
Summary: Self-assembled superparticles composed of colloidal quantum dots are used to create microsphere cavities that support optically pumped lasing from whispering gallery modes. The lasing properties of CdSe/CdS quantum dot superparticles are found to be dependent on the excitation fluence and time, with blue-shifts occurring over a 15-minute period. A high-fluence light soaking protocol is established to counter this effect, resulting in reduced blue-shifts and enabling color-tunable lasing from red to green. This study suggests that quantum dot superparticles have the potential to be low-cost, robust, solution-processable, and tunable microlasers.
Article
Chemistry, Multidisciplinary
Jeffrey M. McNeill, Yun Chang Choi, Yi-Yu Cai, Jiacen Guo, Francois Nadal, Cherie R. Kagan, Thomas E. Mallouk
Summary: This study reports the assembly and phase separation of microspinners powered by sound waves. A phase diagram is constructed by studying the interactions between spinners at different densities, showing gaseous dimer pairing, collective rotation, multiphase separation, and jamming. The observations are consistent with recent theoretical predictions and provide an exciting experimental window for the study of colloidal active matter and microrobotic systems.
Article
Chemistry, Multidisciplinary
Rito Yanagi, Tianshuo Zhao, Matthew Cheng, Bin Liu, Haoqing Su, Chengxing He, Jake Heinlein, Shomeek Mukhopadhyay, Haiyan Tan, Devan Solanki, Shu Hu
Summary: Photocatalytic CO2 reduction in low CO2 concentration is challenging but has important applications in carbon capture and achieving circular carbon economy. The interplay between CO2 catalytic reduction and oxidative redox processes on photocatalyst surfaces with nanometer-scale distances needs more investigation. This study achieved solar-to-fuel conversion efficiency for CO production using Ag@CrOx nanoparticles supported on GaInP2 photocatalytic panel. The study shows that light-driven CO2 reduction and CO2 reactive transport are mutually dependent, providing insights for understanding and manipulating CO2 reduction activity and selectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
