Article
Materials Science, Multidisciplinary
Ewelina Mackiewicz, Tomasz Wejrzanowski, Remigiusz Nowacki, Jakub Jaroszewicz, Jakub Marchewka, Lukasz Wilk, Patryk Bezkosty, Maciej Sitarz
Summary: Material extrusion is a commonly used 3D printing technique, particularly for ceramics as support materials. This article demonstrates the development of silica-nickel porous structures via material extrusion and the optimization of thermal processing conditions. It shows the potential application of material extrusion as a technique for printing highly porous materials with well-preserved 3D geometry.
APPLIED MATERIALS TODAY
(2023)
Article
Materials Science, Multidisciplinary
K. Sowards, H. Medina
Summary: This review introduces hierarchical enhanced surface area structures (HESAS) and their performance-enhancing benefits in various domains such as biology, medicine, environmental engineering, chemical engineering, energy conversion/storage, and sensors. Specific applications include disinfection and antisepsis, water purification, photocatalytic degradation, photokilling of malignant cells, energy generation, energy storage, and sensors. Flower-like structures and formation of titania are emphasized as important categories and examples of HESAS.
APPLIED MATERIALS TODAY
(2023)
Article
Materials Science, Composites
Wei Zhang, Renjie Zhang, Yanli Tan, Yun Xue, Jidong Dong, Lina Ma, Zaixing Jiang, Yudong Huang
Summary: By utilizing a simple method, micro/mesoporous S-NiCo2O4/AC hybrids with abundant vacancy defects were designed, exhibiting superior structural durability, good electrical conductivity, and rich active sites, leading to excellent energy density and power density.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Polymer Science
Zengyong Chu, Guochen Li, Xiaofeng Gong, Zhenkai Zhao, Yinlong Tan, Zhenhua Jiang
Summary: This study demonstrates the use of reduced graphene oxide (RGO) with hierarchical oriented wrinkle microstructures, generated using a two-step shrinkage of a rubber substrate, for preparing high-performance electronic materials with adjustable strain sensitivity and different levels of wrinkles. The sensors exhibit improved GF values range and stability, showing potential for monitoring vital signs and large motions in various health or motion monitoring fields.
Article
Engineering, Environmental
Haiyang Zhou, Dongxian Wen, Xiaolong Hao, Chuanfu Chen, Nianhan Zhao, Rongxian Ou, Qingwen Wang
Summary: This study successfully deposited nanosized zinc borate particles in the hierarchical void system of wood through biomineralization, resulting in the fabrication of nanostructured wood hybrids with efficient flame retardancy, smoke suppression, mold resistance, and antitermite activity. The mineralized wood exhibited excellent heat insulation performance, reduced the release of harmful gases and smoke, and had properties of mold resistance and antitermite activity. This study provides a feasible strategy for manufacturing multifunctional wood.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Biophysics
Yu-Chih Lin, Yi-Ping Fang, Chi-Feng Hung, Huang-Ping Yu, Ahmed Alalaiwe, Zhi-Yuan Wu, Jia-You Fang
Summary: TiO2 in mesoporous silica (SBA-15) showed efficient UV protection and pollutant absorption. Different amounts of TiO2 affected the pore size of SBA-15. The formulation with TiO2 demonstrated enhanced skin protection and reduced skin damage in mice.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Denis Nazarov, Lada Kozlova, Aida Rudakova, Elena Zemtsova, Natalia Yudintceva, Elizaveta Ovcharenko, Alexandra Koroleva, Igor Kasatkin, Ludmila Kraeva, Elizaveta Rogacheva, Maxim Maximov
Summary: Atomic layer deposition (ALD) was used to grow zinc-titanium oxide nanofilms with different ratios of ZnO and TiO2. Characterization techniques such as spectral ellipsometry, X-ray reflectometry, X-ray diffraction, scanning electron microscopy, SEM-EDX, and contact angle measurements were used to evaluate the thickness, morphology, and composition of the films. The results showed that the thickness of the coatings deviated from the rule of mixtures, with higher ZnO/TiO2 ratios resulting in lower thickness and higher titanium oxide content leading to increased thickness. The ZTO samples also exhibited antibacterial properties and did not negatively affect human mesenchymal stem cells, suggesting their potential for medical applications.
Article
Chemistry, Inorganic & Nuclear
Amir Said, Guanyun Zhang, Dexin Wang, Guanjie Chen, Yanshu Liu, Fangfang Gao, Chen-Ho Tung, Yifeng Wang
Summary: Five cluster polymers based on heterometal-doped titanium-oxide cluster (TOC) monomers were reported. These polymers showed photo-catalytic activity in H-2 evolution and CO2/epoxide cycloaddition reactions, with their properties depending on the heterometal dopants. The tunable compositions and topologies of the cluster polymers may inspire the design of more functional metal-oxide cluster materials in the future.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Shuaiqiang Jia, Qinggong Zhu, Mengen Chu, Shitao Han, Ruting Feng, Jianxin Zhai, Wei Xia, Mingyuan He, Haihong Wu, Buxing Han
Summary: The study presents a novel method for synthesizing 3D hierarchical metal/polymer-carbon paper electrodes through in situ electrosynthesis, which can efficiently reduce CO2 to desired products depending on the metal used. The critical factors for the excellent performance are the 3D hierarchical structure of the metals and the in situ formation of the electrodes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Optics
Chunfang Guo, Meiju Zhang, Jun Hu
Summary: This study utilizes nanosecond laser ablation and chemical treatment to create distinct pits with hierarchical structures on titanium alloy, achieving superhydrophobicity. The number of scans and scanning space are found to be important factors that affect surface morphology and wettability.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Engineering, Environmental
Daina Romeo, Roland Hischier, Bernd Nowack, Peter Wick
Summary: The scarcity of animal toxicological data for nanomaterials can be addressed by using in vitro data to calculate nanomaterials' effect factors. This study presents a step-by-step procedure to estimate human Benchmark Doses and in vitro-based EFs for several inhaled nanomaterials. The results show that the in vitro-based EFs for TiO2 and amorphous silica are in a similar range, and the animal species selected for testing significantly impact the results.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Saehan Choi, Jeonga Kim, Rafia Tasnim Rahman, Dong Jae Lee, Kimoon Lee, Yoon Sung Nam
Summary: This study presents plastic-free silica-titania-tannin hybrids that enhance the blocking effects of UV-to-blue light while suppressing the generation of reactive oxygen species (ROS). The results demonstrate the promising application of these hybrids in protecting the skin from UV and blue light-induced damage.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Chang Su, Zheng Cao, Jiahao Liu, Xiaojie Sun, Kaijin Qiu, Yuzhi Mu, Xin Cong, Xiaoye Wang, Xiguang Chen, Nan Jia, Chao Feng
Summary: We developed a Ca2+ modified diatom biosilica-based hemostat (DBp-Ca2+) with a hierarchical porous structure. The unique porous size arrangement of DBp-Ca2+ allows for selective adsorption during coagulation process, resulting in rapid hemorrhage control. In vitro and in vivo studies confirmed that DBp-Ca2+ has high porosity, water absorption, protein absorption, and can accelerate blood exchange and reduce thrombosis time.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Meng Zhang, Qingqing Chen, Jingjing Zhang, Guodong Li, Sailong Xu, Lan Yang, Ying Guo
Summary: Controllable composites of Li+-doped ZnO with hierarchical spindle structures were successfully prepared in this study. By introducing Li+ as a cation with strong adsorption capacity, the humidity sensing performance of the hierarchical spindle was greatly improved and became controllable. Li+-doped ZnO composite not only maintained the hierarchical spindle structure, but also improved the adsorption speed and reduced the response time.
Article
Chemistry, Physical
Yu Tang, Xiaolong Yang, Yao Wu, Ligeng Wang, Di Zhu
Summary: The research explores the fabrication of multi-scale titanium dioxide structures using ultraviolet laser irradiation. The study delves into the impact of laser irradiation intensity on material ablation state and water transport performance, highlighting the significant role of microcavities in enhancing water transport performance and the abnormal narrowing of microcavities with an increase in laser irradiation cycles.
APPLIED SURFACE SCIENCE
(2022)
Correction
Chemistry, Physical
Fang Luo, Aaron Roy, Luca Silvioli, David A. Cullen, Andrea Zitolo, Moulay Tahar Sougrati, Ismail Can Oguz, Tzonka Mineva, Detre Teschner, Stephan Wagner, Ju Wen, Fabio Dionigi, Ulrike I. Kramm, Jan Rossmeisl, Frederic Jaouen, Peter Strasser
Article
Chemistry, Applied
Divakar R. Aireddy, Amitava Roy, David A. Cullen, Kunlun Ding
Summary: Supported Na-Mn-W oxides on titanate nanowires were found to have similar catalytic performance as the commonly studied MnOx/Na2WO4/SiO2 catalyst, with a synergistic effect between MnOx and WOx sites. The titanate support not only acts as a reservoir for alkali metals, but also stabilizes isolated MnOx species, contributing to the high selectivity toward C2+ products and suppressed COx formation.
Article
Chemistry, Physical
Luigi Osmieri, Yanghua He, Hoon T. Chung, Geoffrey McCool, Barr Zulevi, David A. Cullen, Piotr Zelenay
Summary: Anion exchange membrane water electrolysis is an attractive technology for low-cost generation of green hydrogen by combining the use of noble metal-free catalysts with pure water feed. By addressing drawbacks of other electrolysis technologies, it has the potential to replace them.
JOURNAL OF POWER SOURCES
(2023)
Article
Chemistry, Physical
Xiang Lyu, Tim Van Cleve, Erica Young, Jianlin Li, Haoran Yu, David A. Cullen, K. C. Neyerlin, Alexey Serov
Summary: Proton exchange membrane fuel cells (PEMFCs) powered by green hydrogen (H2) are a promising alternative to traditional hydrocarbon-fueled power generators. However, further improvements are needed in efficiency, durability, and low-cost production for widespread adoption. Most strategies to improve PEMFC electrodes utilize single material sets, but anisotropic electrode structures with locally tunable properties may offer enhanced performance due to improved transport.
JOURNAL OF POWER SOURCES
(2023)
Article
Chemistry, Physical
Leiming Hu, Tim Van Cleve, Haoran Yu, Jae Hyung Park, Nancy Kariuki, A. Jeremy Kropf, Rangachary Mukundan, David A. Cullen, Deborah J. Myers, K. C. Neyerlin
Summary: The degradation of polymer electrolyte membrane fuel cells (PEMFCs) catalyst layers for heavy-duty vehicles was studied using a catalyst-specific accelerated stress test (AST). The PtCo/HSC catalyst showed better initial mass activity, larger initial mass transport loss, and faster degradation compared to a-Pt/HSC and Pt/HSC catalysts. Pt dissolution resulted in ECSA losses, either by catalyst particle growth or redeposition in the membrane.
JOURNAL OF POWER SOURCES
(2023)
Article
Electrochemistry
ChulOong Kim, Ivy Wu, Mei-Chen Kuo, Dominic J. Carmosino, Ethan W. Bloom, Soenke Seifert, David A. Cullen, Phuc Ha, Matthew J. Lindell, Ruichun Jiang, Craig S. Gittleman, Michael A. Yandrasits, Andrew M. Herring
Summary: Commercial proton exchange membrane heavy-duty fuel cell vehicles require a more durable composite membrane that can potentially conduct protons. We developed a composite membrane incorporating silicotungstic heteropoly acid (HPA) and other materials, which showed less swelling, more hydrophobic properties, and higher crystallinity than conventional membranes. This composite membrane demonstrated a proton conductivity of 0.130 +/- 0.03 S cm(-1) at 80 degrees C and 95% RH, and survived more than 800 hours under accelerated stress test conditions.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Electrochemistry
Krysta Waldrop, John J. Slack, Cenk Gumeci, Javier Parrondo, Nilesh Dale, Kimberly Shawn Reeves, David A. Cullen, Karren L. More, Peter N. Pintauro
Summary: MEA with nanofiber mat electrodes containing Pt/C catalyst and Nafion binder were fabricated and evaluated. The electrodes were prepared by electrospinning a solution of catalyst powder, salt-form Nafion, and a carrier polymer. MEAs with anode/cathode catalyst loadings of 0.1 mg(Pt) cm(-2) each and a Nafion 211 membrane demonstrated high power at both high and low RH conditions in H-2/air fuel cell tests. The presence of nm-size pores within the fibers trapped water via capillary condensation, maintaining high proton conductivity of the Nafion binder.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Electrochemistry
Kaur Muuli, Xiang Lyu, Marek Mooste, Maike Kaarik, Barr Zulevi, Jaan Leis, Haoran Yu, David A. Cullen, Alexey Serov, Kaido Tammeveski
Summary: In this study, Fe-N-C catalysts were prepared at a kilogram scale using the commercial VariPoreTM method, and the effect of synthesis conditions on the catalyst performance at ZAB air electrode was investigated. The results showed that the PA-450-HT catalyst exhibited excellent electrocatalytic activity for the oxygen reduction reaction (ORR) and was the most suitable catalyst for primary ZAB, with a galvanostatic polarization discharge peak power density of 149 mW cm-2, outperforming commercial Pt-Ru/C catalysts. Additionally, the NCB-600-HT catalyst displayed outstanding ORR and OER reversibility, with a half-wave potential of 0.87 V vs. RHE and a Delta E value of 0.81 V, and exhibited excellent charge-discharge cycling durability similar to NCB-550-LT for the secondary ZAB. This study reported for the first time the mass production of outstanding bifunctional Fe-N-C catalysts for rechargeable ZAB.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Physical
D. P. Leonard, S. Komini Babu, J. S. Baxter, H. M. Meyer, D. A. Cullen, R. L. Borup
Summary: The high production cost of gas diffusion layer (GDL) in proton exchange membrane fuel cells is mainly due to the use of polyacrylonitrile (PAN) fibers. This study examines the performance of inexpensive natural fiber-based papers and fabric as GDLs, and the improvements achieved by incorporating a microporous layer, gas-phase hydrophobic treatment, and densification. The resulting GDLs demonstrate comparable performance to the commercial baseline GDL and highlight the potential of reducing GDL manufacturing costs.
JOURNAL OF POWER SOURCES
(2023)
Article
Polymer Science
Sunilkumar Khandavalli, Yingying Chen, Nisha Sharma-Nene, Kashyap Sundara Rajan, Samrat Sur, Jonathan P. Rothstein, Kimberley S. S. Reeves, David A. A. Cullen, K. C. Neyerlin, Scott A. A. Mauger, Michael Ulsh
Summary: We investigated the effect of alcohol fraction in a binary water-alcohol solvent mixture on the rheological properties and fiber formation of poly(acrylic acid) in electrospinning. We found that the addition of alcohol induces association/aggregation of the polymer, which affects its viscosity and elasticity. The presence of alcohol also stabilizes the jets/filaments during electrospinning, resulting in improved fiber formation.
JOURNAL OF POLYMER SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
X. Lyu, T. Zhang, Z. Li, C. J. Jafta, A. Serov, I. -H. Hwang, C. Sun, D. A. Cullen, J. Li, J. Wu
Summary: This study investigates the effect of trace Cu loading on metal-free catalysts for CO/CO2 reduction reactions (CORR). It is found that increasing Cu loading switches the selectivity from C1 (CH4) to C2 products in CORR. At a Cu loading of 2.5 mu g/cm2, the Faradaic efficiency of CH4 in CORR decreased from 62% to 52% for C2 products. Further increasing the atomic Cu loading to 3.8 mu g/cm2 promotes the Faradaic efficiency of C2 products to 78%. CO2RR requires higher Cu loading than CORR to switch the selectivity from C1 to C2 products. This study clarifies the distinct impact of trace Cu on the activity/selectivity between CORR and CO2RR.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Electrochemistry
Xiang Lyu, Dimitra Anastasiadou, Jithu Raj, Jingjie Wu, Yaocai Bai, Jianlin Li, David A. Cullen, Jun Yang, Liliana P. L. Gonsalves, Oleg I. Lebedev, Yury V. Kolen'ko, Marta Costa Figueiredo, Alexey Serov
Summary: A facile approach for synthesizing M-N-C catalysts (M = Co, Fe, Ni) without organic solvents at a commercial scale is reported. Single atomic catalysts with high surface areas were successfully obtained. Among the synthesized catalysts, Ni-N-C exhibited the highest performance in the electrochemical CO2 reduction reaction, with 80% Faradaic efficiency of CO production at -0.49 VRHE and a turnover frequency of 57,379 h-1. The large-scale synthesis and high performance of M-N-C catalysts enable their practical implementation in industrially relevant CO2RR.
ELECTROCHIMICA ACTA
(2023)
Article
Materials Science, Multidisciplinary
J. David Arregui-Mena, Philip D. Edmondson, David Cullen, Samara Levine, Cristian Contescu, Yutai Katoh, Nidia Gallego
Summary: In the 1960s, the feasibility of molten salt reactors for civil applications was demonstrated by the Molten Salt Reactor Experiment using CGB graphite as the fast neutron moderator. Additional impregnation steps were taken to reduce molten salt ingression, but little information has been published about the microstructure or sealant of this graphite grade. The study presents advanced microscopy results and investigates the sealing technology of legacy material from the Molten Salt Reactor Experiment, providing insights for potential reutilization in modern reactors.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Qing Gong, Hong Zhang, Haoran Yu, Sungho Jeon, Yang Ren, Zhenzhen Yang, Cheng-Jun Sun, Eric A. Stach, Alexandre C. Foucher, Yikang Yu, Matthew Smart, Gabriel M. Filippelli, David A. Cullen, Ping Liu, Jian Xie
Summary: Researchers have developed a simple method to deposit sub-3-nm L10-PtM nanoparticles onto carbon supports, resulting in improved Pt utilization and mass transport in polymer electrolyte membrane fuel cells. This approach achieved excellent oxygen reduction reaction activity, high power density, and durability, meeting the targets set by the Department of Energy.
Article
Nanoscience & Nanotechnology
Kui Li, Lei Ding, Zhiqiang Xie, Gaoqiang Yang, Shule Yu, Weitian Wang, David A. Cullen, Harry M. Meyer III, Guoxiang Hu, Panchapakesan Ganesh, Thomas R. Watkins, Feng-Yuan Zhang
Summary: Electrochemical conversion of nitrogen to green ammonia is hindered by the lack of efficient electrocatalysts. In this study, a cost-effective bimetallic Ru-Cu mixture catalyst in a nanosponge architecture was designed. The optimized Ru0.15Cu0.85 NS catalyst exhibited impressive N2RR performance and superior stability, surpassing monometallic Ru and Cu nanostructures. This work contributes to the design of efficient electrocatalysts for ambient electrochemical ammonia production.
ACS APPLIED MATERIALS & INTERFACES
(2023)
