Publications related to Base (chemistry)

Silicon microresonator arrays: A comprehensive study on fabrication techniques and pH-controlled stress-induced variations in cantilever stiffness

Luis Guillermo Villanueva Torrijo, Annalisa De Pastina

We introduce a detailed design and fabrication process of Silicon microcantilever arrays for biomolecular detection in liquid environment, utilized with laser readout. We present typical fabrication problems and provide related solutions to obtain high qua ...

Elsevier2024

Engineering Frustrated Lewis Pair Active Sites in Porous Organic Scaffolds for Catalytic CO2 Hydrogenation

Rubén Laplaza Solanas, Anne-Clémence Corminboeuf, Jacob Terence Blaskovits, Shubhajit Das

Frustrated Lewis pairs (FLPs), featuring reactive combinations of Lewis acids and Lewis bases, have been utilized for myriad metal-free homogeneous catalytic processes. Immobilizing the active Lewis sites to a solid support, especially to porous scaffolds, ...

Amer Chemical Soc2024

New Applications of 1,3,2-Diazaphospholenes in Catalysis

Johannes Klett

The constant urge to construct new molecules in an economical and sustainable fashion led to the development of numerous metal-catalyzed transformations. Organocatalysts consisting of abundant and more sustainable elements offer an elegant solution to over ...

EPFL2024

Electro- and photochemical H-2 generation by Co(ii) polypyridyl-based catalysts bearing ortho-substituted pyridines

Rosario Scopelliti, Euro Solari, Albert Ruggi, Vincent Artero, Fiorella Lucarini

Cobalt(II) complexes featuring hexadentate amino-pyridyl ligands have been recently discovered as highly active catalysts for the Hydrogen Evolution Reaction (HER), whose high performance arises from the possibility of assisting proton transfer processes v ...

ROYAL SOC CHEMISTRY2023

How Robust Is the Reversible Steric Shielding Strategy for Photoswitchable Organocatalysts?

Anne-Clémence Corminboeuf, Simone Gallarati, Raimon Fabregat I De Aguilar-Amat, Veronika Juraskova, Théo Pierre Jaffrelot Inizan

A highly appealing strategy to modulate a catalyst's activity and/or selectivity in a dynamic and noninvasive way is to incorporate a photoresponsive unit into a catalytically competent molecule. However, the description of the photoinduced conformational ...

AMER CHEMICAL SOC2022

Effect of alkali, aluminium and equilibration time on calcium-silicate-hydrates

Yu Yan

Calcium silicate hydrate (C-S-H) is the main hydration product in Portland and blended cements, and greatly affects durability and mechanical properties of the hydrated cement. In the presence of Al-rich supplementary cementitious materials (SCMs), C-(A-)S ...

EPFL2022

Synthetic chemistry with nitrous oxide and triazenes

Iris Roswitha Landman

Nitrous oxide (N2O) has gained much interest because of its physiological effects ("laughing gas") and its negative environmental impact ("greenhouse gas", "ozone-depleting substance"): It has a lifetime of more than 100 years in the atmosphere. Its persis ...

EPFL2022

Effect of alkali hydroxide on calcium silicate hydrate (C-S-H)

Karen Scrivener, Barbara Lothenbach, Yu Yan, Émilie Michèle L'Hôpital, Sheng-Yu Yang

This paper investigates the effect of KOH and NaOH on C-S-H structure and solubility. Both KOH and NaOH have a similar effect, they increase pH values and silicon concentrations, and decrease calcium concentrations. At higher alkali hydroxide concentration ...

Pergamon-Elsevier Science Ltd2022

Water Orientation at the Anatase TiO2 Nanoparticle Interface: A Probe of Surface pKa Values

Arianna Marchioro, Marie Bischoff

The acid-base properties of surfaces significantly influence catalytic and (photo)electrochemical processes. Estimation of acid dissociation constants (pKa values) for colloids is commonly performed through electroanalytical techniques or spectroscopic met ...

AMER CHEMICAL SOC2022

Al uptake in calcium silicate hydrate and the effect of alkali hydroxide

Karen Scrivener, Barbara Lothenbach, Yan Yan

The effect of Al and of pH on the structure of calcium silicate hydrate (C-S-H), the most important hydration product in Portland and blended cement, was studied at Ca/Si similar to 1.0. The presence of Al led to higher amounts of secondary phases, larger ...

Pergamon-Elsevier Science Ltd2022

Active sites on copper-based catalysts for electrochemical CO2 reduction selectively to C2+ products

Jie Zhang

Electrochemical CO2 reduction (eCO2RR) towards value-added chemicals, powered by renewable electricity, is a promising technology for storing the intermittent renewable energy in the form of chemical bonds. Among the various products of eCO2RR, multi-carbo ...

EPFL2022

Recent Advances in Group 14 and 15 Lewis Acids for Frustrated Lewis Pair Chemistry

Shubhajit Das

Frustrated Lewis pairs (FLP) which rely on the cooperative action of Lewis acids and Lewis bases, played a prominent role in the advancement of main-group catalysis. While the early days of FLP chemistry witnessed the dominance of boranes, there is a growi ...

WILEY-V C H VERLAG GMBH2022

Effect of different ions on dissolution rates of silica and feldspars at high pH

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri, Mahdieh Shakoorioskooie

The dissolution kinetics of silica-containing minerals in aggregates influences strongly the process of ASR in concrete. In this paper, the effect of different ions on the dissolution rates of SiO2 (amorphous and quartz) and feldspars at high pH values was ...

Pergamon-Elsevier Science Ltd2022

In Situ Monitoring of the Surface Evolution of a Silver Electrode from Polycrystalline to Well-Defined Structures

Yunchang Liang

Capturing the surface-structural dynamics of metal electrocatalysts under certain electrochemical environments is intriguingly desired for understanding the behavior of various metal-based electrocatalysts. However, in situ monitoring of the evolution of a ...

AMER CHEMICAL SOC2022

Molecular insights into the electrical double layer of colloidal oxide particles obtained through second harmonic scattering

Marie Bischoff

Photocatalytic applications play an essential role in the search for alternative energy sources and environmental decontamination techniques. It is of fundamental interest to understand on a molecular level the aqueous solid/liquid interface, where photoca ...

EPFL2022

Bulk Heterojunction Organic Semiconductor Photoanodes: Tuning Energy Levels to Optimize Electron Injection

Kevin Sivula, Jun Ho Yum, Liang Yao, Nestor Guijarro Carratala, Yongpeng Liu, Arvindh Sekar, Han-Hee Cho, Barbara Alexandra Primera Darwich, Juan Manuel Moreno Naranjo

The use of a bulk heterojunction of organic semiconductors to drive photoelectrochemical water splitting is an emerging trend; however, the optimum energy levels of the donor and acceptor have not been established for photoanode operation with respect to e ...

AMER CHEMICAL SOC2022

Structure analysis of beta dicalcium silicate via scanning transmission electron microscope (STEM)

Franco Alberto Zunino Sommariva, Qiao Wang, Junying Zhao, Chaoqi Shi

Beta-dicalcium silicate (beta-C2S), one of the main phases in Portland cement clinker, offers some promising overviews regarding CO2 and energy savings potential compared to alite. Understanding the crystalline structure and reactive sites on beta-C2S surf ...

ELSEVIER SCI LTD2022

Mechanistic classification and benchmarking of polyolefin depolymerization over silica-alumina-based catalysts

Paul Joseph Dyson, Mounir Driss Mensi, Felix Daniel Bobbink, Antoine Philippe Van Muyden, Wei-Tse Lee, Jed Russell Carullo

Carbon-carbon bond cleavage mechanisms play a key role in the selective deconstruction of alkanes and polyolefins. Here, we show that the product distribution, which encompasses carbon range and formation of unsaturated and isomerization products, serves a ...

Nature Research2022

Expiratory Aerosol pH: The Overlooked Driver of Airborne Virus Inactivation

Tamar Kohn, Athanasios Nenes, Kalliopi Violaki, Ghislain Gilles Jean-Michel Motos, Walter Hugentobler, Aline Laetitia Schaub, Shannon Christa David

Respiratory viruses, including influenza virus and SARS-CoV-2, are transmitted by the airborne route. Air filtration and ventilation mechanically reduce the concentration of airborne viruses and are necessary tools for disease mitigation. However, they ign ...

2023

Development of C-C and C-O bond cleavage catalysts for the depolymerization of plastics

Wei-Tse Lee

Chemical recycling of plastics provides more flexibility for materials circulation than landfill disposal or incineration. Intensive research efforts have been devoted to maximizing the efficiency of chemical recycling through catalyst development. The fro ...

EPFL2022