Article
Chemistry, Physical
Katja Li, Sarah G. Shapel, Degenhart Hochfilzer, Jakob B. Pedersen, Kevin Krempl, Suzanne Z. Andersen, Rokas Sazinas, Mattia Saccoccio, Shaofeng Li, Debasish Chakraborty, Jakob Kibsgaard, Peter C. K. Vesborg, Jens K. Norskov, Ib Chorkendorff
Summary: The current density and ammonia formation rates were significantly improved by synthesizing high surface area Cu electrodes through hydrogen bubbling templating (HBT) on Ni foam substrates. Increasing the electrolyte salt concentration was found to enhance the stability of the system.
ACS ENERGY LETTERS
(2022)
Review
Chemistry, Multidisciplinary
Muhammad Ibrar Ahmed, Aya Assafiri, David Brynn Hibbert, Chuan Zhao
Summary: The electrochemical nitrogen reduction reaction has great potential for sustainable ammonia production using electricity from renewable energy sources. However, challenges such as low nitrogen solubility, poor kinetics, and competition from the hydrogen evolution reaction have limited ammonia production rates. The Li-mediated electrochemical nitrogen reduction strategy has been proven to be effective in achieving significant ammonia yields. This article summarizes the advances and insights into the Li-mediated strategy, including the role of lithium, reaction parameters, cell designs, and mechanistic evaluation, and presents the challenges and prospects of this strategy for sustainable ammonia production as a continuous, stable, and modular approach.
Article
Engineering, Environmental
Tingting Wang, Zongkui Kou, Jian Zhang, Huide Wang, Yu-Jia Zeng, Songrui Wei, Han Zhang
Summary: The study developed a novel electrocatalyst for improving the efficiency of ammonia synthesis through theoretical calculations and experimental methods, which showed high Faradaic efficiency and ammonia yield rate, along with excellent stability.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Physical
Na Cao, Zengxi Wei, Jie Xu, Jun Luo, Anxiang Guan, Abdullah M. Al-Enizi, Jianmin Ma, Gengfeng Zheng
Summary: The study demonstrated the successful development of a bi-metallic Sn-Ti structure in TiO2 for efficient electrocatalytic N-2 fixation, highlighting the potential of atomic-scale designing and constructing bimetallic active sites.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Yang Bao, Jinxin Hao, Shu Zhang, Dechun Zhu, Feihu Li
Summary: Prussian blue analogs (PBAs), including nickel hexacyanoferrate (NiHCF) electrodes, can be tailored structurally and compositionally to enhance capacitive deionization (CDI) performance. Hierarchically structured NiHCF nanoframe (NiHCF-NF) electrodes exhibit superior desalination capacity, charge efficiency, capacity retention, and selectivity towards monovalent sodium ions (Na+). Coating NiHCF with carbon film decreases desalination capacity, while the hierarchical NiHCF-NF electrode shows promise for selectively capturing Na+ ions from brines. Overall, structural/compositional tailoring strategies offer viable options for designing intercalation electrode materials for CDI techniques.
Article
Chemistry, Physical
Yongwen Ren, Chang Yu, Xiaotong Han, Xinyi Tan, Qianbing Wei, Wenbin Li, Yingnan Han, Le Yang, Jieshan Qiu
Summary: This study demonstrates an innovative alcohol-water electrolyte system to modulate local proton concentration and the microenvironment at the electrode-electrolyte interface, boosting the selectivity of NRR. The methanol-enabled electrolyte shows record high NRR FE and ammonia yield rate, with significant enhancements compared to conventional aqueous electrolytes.
ACS ENERGY LETTERS
(2021)
Review
Chemistry, Physical
Soma Vesztergom, Abhijit Dutta, Motiar Rahaman, Kiran Kiran, Ivan Zelocualtecatl Montiel, Peter Broekmann
Summary: The electrochemical deposition of metal foams around co-generated hydrogen bubbles that act as templates for the deposition is a promising, cheap and simple approach to the fabrication of new electrocatalyst materials. Metal foams obtained by dynamic hydrogen bubble templating offer an intrinsically high electrical conductance with an open porous structure that enables the fast transport of gases and liquids. The confined space within the pores of these metal foams may act as small reactors that can harbor reactions not possible at an open electrode interface.
Article
Chemistry, Physical
Kayaramkodath C. Ranjeesh, Sukhjot Kaur, Abdul K. Mohammed, Safa Gaber, Divyani Gupta, Khaled Badawy, Mohamed Aslam, Nirpendra Singh, Tina Skorjanc, Matjaz Finsgar, Jesus Raya, Tharamani C. Nagaiah, Dinesh Shetty
Summary: This study reports a covalent organic framework catalyst with in-situ proton filter ability, which can effectively control proton supply and enhance N2 flux for efficient nitrogen reduction reaction. The feasibility of the catalyst is further validated through molecular dynamics simulations and control experiments. These findings signify a paradigm shift in engineering high-performance NRR electrocatalysts and contribute to more feasible green NH3 production.
ADVANCED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Hsiao-Yun Liu, Shih-Fang Lin, Da-Wei Lee, Justin Chou, Sheng-Wei Lee, Kuan-Wen Wang
Summary: This study focuses on the design and preparation of binary In-Sn catalysts for the electrochemical CO2 reduction reaction (CO2RR). The results show that In3Sn/C nanoparticles exhibit outstanding performance with high formate conversion. This research provides guidance for the optimization of catalyst compositions and structures for CO2RR.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Qi Hu, Yongjie Qin, Xiaodeng Wang, Ziyu Wang, Xiaowan Huang, Hongju Zheng, Keru Gao, Hengpan Yang, Peixin Zhang, Minhua Shao, Chuanxin He
Summary: The study demonstrates that in alkaline media, the NH3 yield rate catalyzed by defective Cu(100) facets in NO3-RR is 2.3 times higher than that of the Haber-Bosch process. It is discovered that the intermediates of NO3-RR, N*, can serve as capping agents for controlling the exposed facets during the reduction.
ENERGY & ENVIRONMENTAL SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Hoang-Long Du, Karolina Matuszek, Rebecca Y. Hodgetts, Khang Ngoc Dinh, Pavel V. Cherepanov, Jacinta M. Bakker, Douglas R. MacFarlane, Alexandr N. Simonov
Summary: Electrochemical lithium-mediated nitrogen reduction can be used to synthesize ammonia from renewables, but integrating it into electrolyzer devices is challenging due to the lack of understanding of the relationship between performance and proton transport parameters. In this study, a top-performance N-2 electroreduction system was used to investigate the correlation between reaction metrics and proton carrier properties, including alcohols, a phosphonium cation, tetrahydrofuran, a Bronsted acid, ammonium, and water. The study showed that optimized electrolyte compositions are required for productive carriers, and ammonia electrosynthesis with the phosphonium cation and iso-propanol achieved performance close to the ethanol benchmark. It was also found that ethanol undergoes irreversible degradation through reaction with oxidized solvent, unlike iso-propanol and phosphonium cation proton carriers.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Dilip Krishnamurthy, Nikifar Lazouski, Michal L. Gala, Karthish Manthiram, Venkatasubramanian Viswanathan
Summary: The study experimentally tested different classes of proton donors and constructed a classification model to distinguish between active and inactive proton donors, predicting nitrogen reduction activity through interpretable data-driven method. Additionally, a deep learning model was utilized to predict parameters, showing that the combined approach of classification and deep learning models outperformed traditional methods.
ACS CENTRAL SCIENCE
(2021)
Article
Nanoscience & Nanotechnology
Xiaobo He, Fengxiang Yin, Xuerui Yi, Tong Yang, Biaohua Chen, Xiang Wu, Shang Guo, Guoru Li, Zhichun Li
Summary: This study achieved extremely high Faradaic efficiency and a high NH3 production rate by using defective UiO-66-NH2 catalyzed with stable superoxide radicals.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Ana S. Fajardo, Paul Westerhoff, Carlos M. Sanchez-Sanchez, Sergi Garcia-Segura
Summary: The study reveals that carbon (as boron-doped diamond) and tin have the highest average selectivity towards nitrogen gas evolution (55% and 64% respectively), outperforming platinum (Pt) which only has 1% selectivity, while having comparable energy efficiencies per order removal of nitrate. Therefore, earth-abundant elements for electrocatalysis show tremendous promise as innovative, low-cost, and sustainable processes for the water treatment marketplace.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Nanoscience & Nanotechnology
Feng-Yang Chen, Zhen-Yu Wu, Srishti Gupta, Daniel J. Rivera, Sten Lambeets, Stephanie Pecaut, Jung Yoon Timothy Kim, Peng Zhu, Y. Zou Finfrock, Debora Motta Meira, Graham King, Guanhui Gao, Wenqian Xu, David A. Cullen, Hua Zhou, Yimo Han, Daniel E. Perea, Christopher L. Muhich, Haotian Wang
Summary: The research team has efficiently converted nitrate, a common pollutant in wastewater and groundwater, into valuable ammonia products using a Ru-dispersed Cu nanowire catalyst through electrochemical methods. This sustainable approach not only treats wastewater but also generates ammonia, but current low catalytic activities pose challenges. However, the team has developed a high-performance catalyst that achieves over 99% nitrate conversion into ammonia and successfully obtains high purity NH4Cl solid and NH3 liquid products.
NATURE NANOTECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Jesus Barrio, Angus Pedersen, Saurav Ch. Sarma, Alexander Bagger, Mengjun Gong, Silvia Favero, Chang-Xin Zhao, Ricardo Garcia-Serres, Alain Y. Li, Qiang Zhang, Frederic Jaouen, Frederic Maillard, Anthony Kucernak, Ifan E. L. Stephens, Maria-Magdalena Titirici
Summary: By coordinating Fe in a highly porous nitrogen-doped carbon support, the utilization of Fe is improved and high-density electrochemical active sites are achieved.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Romain Tort, Olivia Westhead, Matthew Spry, Bethan J. V. Davies, Mary P. Ryan, Maria-Magdalena Titirici, Ifan E. L. Stephens
Summary: The performance of Li-mediated ammonia synthesis has improved significantly since its reintroduction, but the fundamental understanding of this reaction has been slower due to uncontrolled variables. To address this, a nonaqueous LiFePO4 reference electrode was developed, providing a redox anchor for measuring potentials and estimating energy efficiency loss. The relationship between partial current density and potentials was uncovered using this reference, suggesting that only the electrochemical step of lithium plating is involved in the process. The LiFePO4/Li+ equilibrium was also used to probe Li-ion activity changes in situ. The aim is to promote a better understanding of this reaction by developing more defined systems.
ACS ENERGY LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Olivia Westhead, Jesus Barrio, Alexander Bagger, James W. Murray, Jan Rossmeisl, Maria-Magdalena Titirici, Rhodri Jervis, Andrea Fantuzzi, Andrew Ashley, Ifan E. L. Stephens
Summary: This Review provides a coherent comparison of recent progress made in dinitrogen fixation on solid electrodes, homogeneous catalysts, and nitrogenases. By establishing the cross-cutting themes and synergies between these systems, we identify viable avenues for future research.
NATURE REVIEWS CHEMISTRY
(2023)
Article
Energy & Fuels
Carla de Tomas, Sarat Alabidun, Luke Chater, Matthew T. Darby, Federico Raffone, Paolo Restuccia, Heather Au, Magda M. Titirici, Clotilde S. Cucinotta, Maria Crespo-Ribadenyra
Summary: In this study, the effect of sulfur doping on hard carbon anodes for sodium-ion batteries is investigated using a combination of experiments and theory. The hard carbons are synthesized through a two-step process and subsequent sulfur doping is introduced via chemical-vapour deposition. The sulfur-doped hard carbon exhibits enhanced sodium storage capacity and improved cycling reversibility, which is attributed to the increased sodium adsorption energies and facilitated sodium desorption due to the sulfur chemisorbed onto the hard carbon. This study provides insights into the mechanism and opens up possibilities for more efficient sodium-ion batteries.
JOURNAL OF PHYSICS-ENERGY
(2023)
Article
Chemistry, Multidisciplinary
Saurav Ch Sarma, Jesus Barrio, Alexander Bagger, Angus Pedersen, Mengjun Gong, Hui Luo, Mengnan Wang, Silvia Favero, Chang-Xin Zhao, Qiang Zhang, Anthony Kucernak, Maria-Magdalena Titirici, Ifan E. L. Stephens
Summary: The electrochemical CO2 reduction reaction (CO2RR) to value-added chemicals with renewable electricity is a promising method to decarbonize parts of the chemical industry. Single metal atoms in nitrogen-doped carbon (MNC) have emerged as potential electrocatalysts for CO2RR to CO with high activity and faradaic efficiency. The comparison of intrinsic activity of different MNCs reveals the synthesis approach of high temperature pyrolysis and low temperature metalation results in highly meso-porous structures, leading to the highest reported electrochemical active site utilization. The catalysts show promising performance for CO reduction to CO2 and their binding to reaction intermediates approximates to that of Au surfaces.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Multidisciplinary Sciences
Siqi Zhao, Oliver Christensen, Zhaozong Sun, Hongqing Liang, Alexander Bagger, Kristian Torbensen, Pegah Nazari, Jeppe Vang Lauritsen, Steen Uttrup Pedersen, Jan Rossmeisl, Kim Daasbjerg
Summary: This study investigates how the activity and selectivity of Cu electrodes for CO2 reduction can be adjusted by using organic films with different porosity and thickness. The films increase the local CO partial pressures and surface coverages. Copper catalysts have the potential to produce multicarbon compounds in the electrochemical carbon dioxide reduction reaction. Instead of conventional alloying with other elements, copper can be modified with organic molecules to control product distribution. The study reveals that the thickness and porosity of the films have a significant impact on carbon dioxide reduction, leading to an enhancement in current density and selectivity towards multicarbon products.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Amanda S. Petersen, Kim D. Jensen, Hao Wan, Alexander Bagger, Ib Chorkendorff, Ifan E. L. Stephens, Jan Rossmeisl, Maria Escudero-Escribano
Summary: In this study, the effects of phosphate anion poisoning on the oxygen reduction reaction (ORR) activity of Pt-based electrodes were investigated using a computational model and rotating disk electrode measurements. By varying the subsurface Cu content of a Cu/Pt(111) alloy, the *OH binding energies on the surface were tuned through ligand effects, resulting in tuning of the ORR activity. The adsorbed phosphate species on the surface were found to directly affect the adsorption of *OH, and the three-fold binding sites of phosphate anions limited the packing of poisoning phosphate, allowing for *OH adsorption even when the surface was poisoned.
Article
Chemistry, Multidisciplinary
Zamaan Mukadam, Sihang Liu, Angus Pedersen, Jesus Barrio, Sarah Fearn, Saurav Ch. Sarma, Maria-Magdalena Titirici, Soren B. Scott, Ifan E. L. Stephens, Karen Chan, Stefano Mezzavilla
Summary: In this study, Cu and Co single-atom catalysts supported on carbon electrodes were used to investigate the electrochemical reduction of furfural, a biomass-derived chemical. Under mild conditions, hydrofuroin, a valuable precursor to sustainable jet fuels, was selectively produced. The study also revealed insights into the mechanism and stability of the catalysts and provided a blueprint for catalyst design in this reaction.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Physical
O. Westhead, R. Tort, M. Spry, J. Rietbrock, R. Jervis, A. Grimaud, A. Bagger, I. E. L. Stephens
Summary: The verification of the lithium-mediated nitrogen reduction system in 2019 has resulted in an increase in literature on improving the faradaic efficiency, stability, and activity. However, accurately quantifying the overpotential and analyzing voltage losses has been challenging. This study presents a simple method for determining the Reversible Hydrogen Electrode potential in the system and identifies sources of potential losses. The observed minimum overpotential was -3.59 +/- 0.07 V vs. RHE, with a faradaic efficiency of 6.5 +/- 0.2%.
FARADAY DISCUSSIONS
(2023)
Review
Chemistry, Physical
Hans Becker, James Murawski, Dipak V. Shinde, Ifan E. L. Stephens, Gareth Hinds, Graham Smith
Summary: Low temperature water electrolysers are sensitive to water quality and common impurities can affect the device performance and lifetime. Purifying the feed water adds cost and complexity, and failure of purification equipment can cause degradation of the electrolysers. This review provides a comprehensive overview of impurities in operating electrolysers, including their sources, degradation mechanisms, characterization techniques, water purification technologies, and mitigation strategies. It generalizes existing mechanisms, proposes new ones, and offers a framework for considering operational implications.
SUSTAINABLE ENERGY & FUELS
(2023)
Article
Chemistry, Physical
Michael P. Mercer, Mangayarkarasi Nagarathinam, E. Maximiliano Gavilan-Arriazu, Anshika Binjrajka, Swoyam Panda, Heather Au, Maria Crespo-Ribadeneyra, Maria-Magdalena Titirici, Ezequiel P. M. Leiva, Harry E. Hoster
Summary: Hard carbons have potential as anode materials in sodium-ion battery technologies. Understanding the driving forces of sodium insertion into hard carbons, particularly into nanopores, is crucial for material optimization. By using entropy profiling, researchers were able to determine the onset of nanopore filling and quantify the energetics of sodium inside the nanopores, providing insights for tuning the cell cut-off voltage.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Hao Wan, Xingli Wang, Lei Tan, Michael Filippi, Peter Strasser, Jan Rossmeisl, Alexander Bagger
Summary: Electrocatalytic conversion is a promising technology for storing renewable electricity in the chemical form, such as urea production. This study investigated the urea formation mechanism on Cu metal using density functional theory calculations. It was found that Cu can bind with NO and CO but not with H, and through NO and CO coreduction, two possible C-N coupling reactions and subsequent hydrogenation lead to urea formation. This work demonstrates the use of computational simulations in predicting selective and active materials for urea production.
Article
Chemistry, Multidisciplinary
Angus Pedersen, Jinil Pandya, Grazia Leonzio, Alexey Serov, Andrea Bernardi, Ifan E. L. Stephens, Maria-Magdalena Titirici, Camille Petit, Benoit Chachuat
Summary: This study compares the environmental impacts and economic analysis of using non-Pt-based electrocatalyst Fe-N-C to replace Pt/C in PEMFCs. The findings show that Fe-N-C can reduce environmental damages and human health impacts, but it still faces issues such as electricity consumption and resource depletion. The cost of PEMFC stacks with Fe-N-C cathode would increase compared to those with Pt/C cathode due to the increase in environmental externalities. Continued improvement of Fe-N-C performance is necessary to replace Pt-based cathode catalysts in PEMFCs.
