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52. Dual‐analgesic loaded UHMWPE exhibits synergistic antibacterial effects against Staphylococci.

Author

Gil, Dmitry, Hugard, Shannon, Borodinov, Nikolay, Ovchinnikova, Olga S., Muratoglu, Orhun K., Bedair, Hany, and Oral, Ebru

Subjects
ARTIFICIAL joints, STAPHYLOCOCCUS, ARTHROPLASTY, PHARMACOKINETICS, STAPHYLOCOCCUS epidermidis
Abstract

Total joint arthroplasty is one of the most common surgeries in the United States, with almost a million procedures performed annually. Periprosthetic joint infections (PJI) remain the most devastating complications associated with total joint replacement. Effective antibacterial prophylaxis after primary arthroplasty could substantially reduce incidence rate of PJI. In the present study we propose to provide post‐arthroplasty prophylaxis via dual‐analgesic loaded ultra‐high molecular weight polyethylene (UHMWPE). Our approach is based on previous studies that showed pronounced antibacterial activity of analgesic‐ and NSAID‐loaded UHMWPE against Staphylococci. Here, we prepared bupivacaine/tolfenamic acid‐loaded UHMWPE and assessed its antibacterial activity against Staphylococcus aureus and Staphylococcus epidermidis. Dual‐drug loaded UHMWPE yielded an additional 1–2 log reduction of bacteria, when compared with single‐drug loaded UHMWPE. Analysis of the drug elution kinetics suggested that the observed increase in antibacterial activity is due to the increased tolfenamic acid elution from dual‐drug loaded UHMWPE. We showed that the increased fractal dimension of the drug domains in UHMWPE could be associated with increased drug elution, leading to higher antibacterial activity. Dual‐analgesic loaded UHMWPE proposed here can be used as part of multi‐modal antibacterial prophylaxis and promises substantial reduction in post‐arthroplasty mortality and morbidity. [ABSTRACT FROM AUTHOR]

Published
2023
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55. Highly enhanced ferroelectricity in HfO 2 -based ferroelectric thin film by light ion bombardment

Author

Kang, Seunghun, primary, Jang, Woo-Sung, additional, Morozovska, Anna N., additional, Kwon, Owoong, additional, Jin, Yeongrok, additional, Kim, Young-Hoon, additional, Bae, Hagyoul, additional, Wang, Chenxi, additional, Yang, Sang-Hyeok, additional, Belianinov, Alex, additional, Randolph, Steven, additional, Eliseev, Eugene A., additional, Collins, Liam, additional, Park, Yeehyun, additional, Jo, Sanghyun, additional, Jung, Min-Hyoung, additional, Go, Kyoung-June, additional, Cho, Hae Won, additional, Choi, Si-Young, additional, Jang, Jae Hyuck, additional, Kim, Sunkook, additional, Jeong, Hu Young, additional, Lee, Jaekwang, additional, Ovchinnikova, Olga S., additional, Heo, Jinseong, additional, Kalinin, Sergei V., additional, Kim, Young-Min, additional, and Kim, Yunseok, additional

Published
2022
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56. The Role of SnO2Processing on Ionic Distribution in Double-Cation–Double Halide Perovskites

Author

Hysmith, Holland, Park, So Yeon, Yang, Jonghee, Ievlev, Anton V., Liu, Yongtao, Zhu, Kai, Sumpter, Bobby G., Berry, Joseph, Ahmadi, Mahshid, and Ovchinnikova, Olga S.

Abstract

Moving toward a future of efficient, accessible, and less carbon-reliant energy devices has been at the forefront of energy research innovations for the past 30 years. Metal-halide perovskite (MHP) thin films have gained significant attention due to their flexibility of device applications and tunable capabilities for improving power conversion efficiency. Serving as a gateway to optimize device performance, consideration must be given to chemical synthesis processing techniques. Therefore, how does common substrate processing techniques influence the behavior of MHP phenomena such as ion migration and strain? Here, we demonstrate how a hybrid approach of chemical bath deposition (CBD) and nanoparticle SnO2substrate processing significantly improves the performance of (FAPbI3)0.97(MAPbBr3)0.03by reducing micro-strain in the SnO2lattice, allowing distribution of K+from K-Cl treatment of substrates to passivate defects formed at the interface and produce higher current in light and dark environments. X-ray diffraction reveals differences in lattice strain behavior with respect to SnO2substrate processing methods. Through use of conductive atomic force microscopy (c-AFM), conductivity is measured spatially with MHP morphology, showing higher generation of current in both light and dark conditions for films with hybrid processing. Additionally, time-of-flight secondary ionization mass spectrometry (ToF-SIMS) observed the distribution of K+at the perovskite/SnO2interface, indicating K+passivation of defects to improve the power conversion efficiency (PCE) and device stability. We show how understanding the role of ion distribution at the SnO2and perovskite interface can help reduce the creating of defects and promote a more efficient MHP device.

Published
2023
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57. Correction to Microstructural Evaluation of Phase Instability in Large Bandgap Metal Halide Perovskites

Author

Kim, Dohyung, primary, Lim, Jihoo, additional, Lee, Seungmin, additional, Soufiani, Arman Mahboubi, additional, Choi, Eunyoung, additional, Ievlev, Anton V., additional, Borodinov, Nikolay, additional, Liu, Yongtao, additional, Ovchinnikova, Olga S., additional, Ahmadi, Mahshid, additional, Lim, Sean, additional, Sharma, Pankaj, additional, Seidel, Jan, additional, Noh, Jun Hong, additional, and Yun, Jae Sung, additional

Published
2022
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60. Microstructural Evaluation of Phase Instability in Large Bandgap Metal Halide Perovskites

Author

Kim, Dohyung, primary, Lim, Jihoo, additional, Lee, Seungmin, additional, Soufiani, Arman Mahboubi, additional, Choi, Eunyoung, additional, Ievlev, Anton V., additional, Borodinov, Nikolay, additional, Liu, Yongtao, additional, Ovchinnikova, Olga S., additional, Ahmadi, Mahshid, additional, Lim, Sean, additional, Sharma, Pankaj, additional, Seidel, Jan, additional, Noh, Jun Hong, additional, and Yun, Jae Sung, additional

Published
2021
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69. Light-ferroelectric interaction in two-dimensional lead iodide perovskites.

Author

Dohyung Kim, Ievlev, Anton V., Ovchinnikova, Olga S., Kalinin, Sergei V., and Ahmadi, Mahshid

Abstract

The unique physical properties of two-dimensional (2D) metal halide perovskites (MHPs) such as nonlinear optics, anisotropic charge transport, and ferroelectricity have made these materials promising candidates for multifunctional applications. Recently, fluorine derivatives such as 4,4-difluoropiperidinium lead iodide perovskite or (4,4-DFPD, C5H10F2N)2PbI4 have shown strong ferroelectricity as compared to other 2D MHPs. Although it was previously addressed that the ferroelectricity in MHPs can be affected by illumination, the underlying physical mechanisms of light-ferroelectricity interaction in 2D MHPs are still lacking. Here, we explore the electromechanical responses in 4,4-(DFPD)2PbI4 thin films using advanced scanning probe microscopy techniques revealing ferroelectric domain structures. Hysteretic ferroelectric loops measured by contact-Kelvin probe force microscopy are dependent on domain structures under dark conditions, while ferroelectricity weakens under illumination. The X-ray diffraction patterns exhibit significant changes in preferential orientation of individual lattice planes under illumination. Particularly, the reduced intensity of the (1 1 1) lattice plane under illumination leads to transitioning from a ferroelectric to a paraelectric phase. The instability of positive ions, especially molecular organic cations, is observed under illumination by time-of-flight secondary ion mass spectrometry. The combination of crystallographic orientation and chemical changes under illumination clearly contributes to the origin of light-ferroelectricity interaction in 2D (4,4-DFPD, C5H10F2N)2PbI4. [ABSTRACT FROM AUTHOR]

Published
2022
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72. Perovskite Solar Cells: Correlated Electrical and Chemical Nanoscale Properties in Potassium‐Passivated, Triple‐Cation Perovskite Solar Cells (Adv. Mater. Interfaces 17/2020)

Author

Tennyson, Elizabeth M., primary, Abdi‐Jalebi, Mojtaba, additional, Ji, Kangyu, additional, Garrett, Joseph L., additional, Gong, Chen, additional, Pawlicki, Alison A., additional, Ovchinnikova, Olga S., additional, Munday, Jeremy N., additional, Stranks, Samuel D., additional, and Leite, Marina S., additional

Published
2020
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75. Exploration of Electrochemical Reactions at Organic–Inorganic Halide Perovskite Interfaces via Machine Learning in In Situ Time‐of‐Flight Secondary Ion Mass Spectrometry

Author

Higgins, Kate, primary, Lorenz, Matthias, additional, Ziatdinov, Maxim, additional, Vasudevan, Rama K., additional, Ievlev, Anton V., additional, Lukosi, Eric D., additional, Ovchinnikova, Olga S., additional, Kalinin, Sergei V., additional, and Ahmadi, Mahshid, additional

Published
2020
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79. Perovskites: Strain–Chemical Gradient and Polarization in Metal Halide Perovskites (Adv. Electron. Mater. 4/2020)

Author

Liu, Yongtao, primary, Ievlev, Anton V., additional, Collins, Liam, additional, Belianinov, Alex, additional, Keum, Jong K., additional, Ahmadi, Mahshid, additional, Jesse, Stephen, additional, Retterer, Scott T., additional, Xiao, Kai, additional, Huang, Jingsong, additional, Sumpter, Bobby G., additional, Kalinin, Sergei V., additional, Hu, Bin, additional, and Ovchinnikova, Olga S., additional

Published
2020
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80. Strain–Chemical Gradient and Polarization in Metal Halide Perovskites

Author

Liu, Yongtao, primary, Ievlev, Anton V., additional, Collins, Liam, additional, Belianinov, Alex, additional, Keum, Jong K., additional, Ahmadi, Mahshid, additional, Jesse, Stephen, additional, Retterer, Scott T., additional, Xiao, Kai, additional, Huang, Jingsong, additional, Sumpter, Bobby G., additional, Kalinin, Sergei V., additional, Hu, Bin, additional, and Ovchinnikova, Olga S., additional

Published
2020
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83. Correlated mechanochemicalmaps of Arabidopsis thaliana primary cell walls using atomic forcemicroscope infrared spectroscopy.

Author

Bilkey, Natasha, Huiyong Li, Borodinov, Nikolay, Ievlev, Anton V., Ovchinnikova, Olga S., Dixit, Ram, and Foston, Marcus

Subjects
PLANT cell walls, ARABIDOPSIS thaliana, ATOMIC force microscopy, INFRARED spectroscopy, POLYOXYMETHYLENE
Abstract

Spatial heterogeneity in composition and organisation of the primary cell wall affects the mechanics of cellular morphogenesis. However, directly correlating cell wall composition, organisation and mechanics has been challenging. To overcome this barrier, we applied atomic forcemicroscopy coupled with infrared (AFM-IR) spectroscopy to generate spatially correlated maps of chemical and mechanical properties for paraformaldehyde-fixed, intact Arabidopsis thaliana epidermal cell walls. AFM-IR spectra were deconvoluted by non-negative matrix factorisation (NMF) into a linear combination of IR spectral factors representing sets of chemical groups comprising different cell wall components. This approach enables quantification of chemical composition from IR spectral signatures and visualisation of chemical heterogeneity at nanometer resolution. Cross-correlation analysis of the spatial distribution of NMFs and mechanical properties suggests that the carbohydrate composition of cell wall junctions correlates with increased local stiffness. Together, our work establishes new methodology to use AFM-IR for the mechanochemical analysis of intact plant primary cell walls. [ABSTRACT FROM AUTHOR]

Published
2022
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84. Investigation of Electrode Electrochemical Reactions in CH3 NH3 PbBr3 Perovskite Single-Crystal Field-Effect Transistors

Author

Wang, Junzhan, Senanayak, Satyaprasad P, Liu, Jie, Hu, Yuanyuan, Shi, Yanjun, Li, Zelun, Zhang, Caixin, Yang, Bingyan, Jiang, Longfeng, Di, Dawei, Ievlev, Anton V, Ovchinnikova, Olga S, Ding, Tao, Deng, Huixiong, Tang, Liming, Guo, Yunlong, Wang, Jianpu, Xiao, Kai, Venkateshvaran, Deepak, Jiang, Lang, Zhu, Daoben, Sirringhaus, Henning, Sirringhaus, Henning [0000-0001-9827-6061], and Apollo - University of Cambridge Repository

Subjects
single crystals, perovskite, field-effect transistors (FETs)
Abstract

Optoelectronic devices based on metal halide perovskites, including solar cells and light-emitting diodes, have attracted tremendous research attention globally in the last decade. Due to their potential to achieve high carrier mobilities, organic-inorganic hybrid perovskite materials can enable high-performance, solution-processed field-effect transistors (FETs) for next-generation, low-cost, flexible electronic circuits and displays. However, the performance of perovskite FETs is hampered predominantly by device instabilities, whose origin remains poorly understood. Here, perovskite single-crystal FETs based on methylammonium lead bromide are studied and device instabilities due to electrochemical reactions at the interface between the perovskite and gold source-drain top contacts are investigated. Despite forming the contacts by a gentle, soft lamination method, evidence is found that even at such "ideal" interfaces, a defective, intermixed layer is formed at the interface upon biasing of the device. Using a bottom-contact, bottom-gate architecture, it is shown that it is possible to minimize such a reaction through a chemical modification of the electrodes, and this enables fabrication of perovskite single-crystal FETs with high mobility of up to ≈15 cm2 V-1 s-1 at 80 K. This work addresses one of the key challenges toward the realization of high-performance solution-processed perovskite FETs.

Published
2019
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86. Light–Ferroic Interaction: Light‐Ferroic Interaction in Hybrid Organic–Inorganic Perovskites (Advanced Optical Materials 23/2019)

Author

Liu, Yongtao, primary, Ievlev, Anton V., additional, Collins, Liam, additional, Borodinov, Nikolay, additional, Belianinov, Alex, additional, Keum, Jong K., additional, Wang, Miaosheng, additional, Ahmadi, Mahshid, additional, Jesse, Stephen, additional, Xiao, Kai, additional, Sumpter, Bobby G., additional, Hu, Bin, additional, Kalinin, Sergei V., additional, and Ovchinnikova, Olga S., additional

Published
2019
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88. Light‐Ferroic Interaction in Hybrid Organic–Inorganic Perovskites

Author

Liu, Yongtao, primary, Ievlev, Anton V., additional, Collins, Liam, additional, Borodinov, Nikolay, additional, Belianinov, Alex, additional, Keum, Jong K., additional, Wang, Miaosheng, additional, Ahmadi, Mahshid, additional, Jesse, Stephen, additional, Xiao, Kai, additional, Sumpter, Bobby G., additional, Hu, Bin, additional, Kalinin, Sergei V., additional, and Ovchinnikova, Olga S., additional

Published
2019
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93. Multi-Model Imaging of Local Chemistry and Ferroic Properties of Hybrid Organic-Inorganic Perovskites

Author

Liu, Yongtao, primary, Ievlev, Anton V., additional, Collins, Liam, additional, Belianinov, Alex, additional, Kim, Songkil, additional, Doughty, Benjamin, additional, Jesse, Stephen, additional, Ahmadi, Mahshid, additional, Retterer, Scott T., additional, Xiao, Kai, additional, Sumpter, Bobby G., additional, Kalinin, Sergei V., additional, Hu, Bin, additional, and Ovchinnikova, Olga S., additional

Published
2019
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97. Investigation of Electrode Electrochemical Reactions in CH 3 NH 3 PbBr 3 Perovskite Single‐Crystal Field‐Effect Transistors

Author

Wang, Junzhan, primary, Senanayak, Satyaprasad P., additional, Liu, Jie, additional, Hu, Yuanyuan, additional, Shi, Yanjun, additional, Li, Zelun, additional, Zhang, Caixin, additional, Yang, Bingyan, additional, Jiang, Longfeng, additional, Di, Dawei, additional, Ievlev, Anton V., additional, Ovchinnikova, Olga S., additional, Ding, Tao, additional, Deng, Huixiong, additional, Tang, Liming, additional, Guo, Yunlong, additional, Wang, Jianpu, additional, Xiao, Kai, additional, Venkateshvaran, Deepak, additional, Jiang, Lang, additional, Zhu, Daoben, additional, and Sirringhaus, Henning, additional

Published
2019
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100. Direct Observation of Photoinduced Ion Migration in Lead Halide Perovskites.

Author

Liu, Yongtao, Ievlev, Anton V., Borodinov, Nikolay, Lorenz, Matthias, Xiao, Kai, Ahmadi, Mahshid, Hu, Bin, Kalinin, Sergei V., and Ovchinnikova, Olga S.

Subjects
ION migration & velocity, LEAD halides, OPTOELECTRONICS
Abstract

Unique optoelectronic, electronic, and sensing properties of hybrid organic–inorganic perovskites (HOIPs) are underpinned by the complex interactions between electronic and ionic states. Here, the photoinduced field ion migration in HOIPs is directly observed. Using newly developed local probe time‐resolved techniques, more significant CH3NH3+ migration than I−/Br− migration in HOIPs is unveiled. It is found that light illumination only induces CH3NH3+ migration but not I−/Br− migration. By directly observing temporal changes in bias‐induced and photoinduced ion migration in device conditions, it is revealed that light illumination suppresses the bias‐induced ion redistribution in the lateral device. These findings, being a necessary compensation of previous understandings of ion migration in HOIPs based on simulations and static and/or indirect measurements, offer advanced insights into the distinct light effects on the migration of organic cation and halides in HOIPs, which are expected to be helpful for improving the performance and the long‐term stability of HOIPs optoelectronics. [ABSTRACT FROM AUTHOR]

Published
2021
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