Publications related to Energy transformation

Hybrid organic/metal-oxide shells on semiconductor nanocrystals via colloidal atomic layer deposition

The escalating energy demand and the imperative necessity to reduce the carbon footprint require transformative approaches to energy conversion. Materials chemistry plays a pivotal role in addressing these global challenges by developing novel materials fo ...

EPFL2024

Phase-stable indium sulfide achieves an energy conversion efficiency of 14.3% for solar-assisted carbon dioxide reduction to formate

Michael Graetzel, Jing Gao, Jingshan Luo, Xiaoyu Zhang, Jun Li, Qixing Zhang

Tremendous efforts have been made in developing highly selective catalysts for electrochemical CO 2 conversion to formate. However, the rapid deactivation resulting from structural reconstruction and phase transition poses considerable challenges to the sy ...

Cell Press2024

Synthesis of polysiloxane elastomers modified with sulfonyl side groups and their electromechanical response

Holger Frauenrath, Yauhen Sheima

Dielectric elastomer transducers are elastic capacitors that respond to mechanical or electrical stress. They can be used in applications such as millimeter-sized soft robots and harvesters of the energy contained in ocean waves. The dielectric component o ...

Royal Society of Chemistry2023

Study of the enhanced electricity output of a sliding droplet-based triboelectric nanogenerator for droplet sensor design

Jürgen Brugger, Xia Liu, Wei Xu, Xiaopeng Li

Triboelectric nanogenerators are establishing themselves as promising candidates for realizing high-efficient energy harvesting from largely available droplets. However, the conventional droplet-based liquid-solid triboelectric nanogenerator (DLS-TENG) has ...

Elsevier2022

Compressed natural gas (cng) power system with co2 emissions capture and storage

François Maréchal, Shivom Sharma

CNG power system (1) comprising a storage tank (6) connected fluidically to a fuel conversion system (2) via an energy transfer system (4), the fuel conversion system (2) comprising a power unit using CNG as fuel and generating gas emissions comprising C02 ...

2022

Passive Perching with Energy Storage for Winged Aerial Robots

Dario Floreano, Yegor Piskarev, William John Stewart, Luca Guarino

Perching in unmanned aerial vehicles (UAVs) offers the possibility of extending the range of aerial robots beyond the limits of their batteries. It has been a topic of intense study for multirotor UAVs. Perching in winged UAVs is harder because a kinetic e ...

2021

Isotope dependence of the type I ELMy H-mode pedestal in JET-ILW hydrogen and deuterium plasmas

Henri Weisen, Mikhail Maslov

The pedestal structure, edge transport and linear MHD stability have been analyzed in a series of JET with the ITER-like wall hydrogen (H) and deuterium (D) type I ELMy H-mode plasmas. The pedestal pressure is typically higher in D than in H at the same in ...

IOP Publishing Ltd2021

Control Strategy for the Discharge Phase of an Ultra-High Voltage (>7kV) Bi-Directional Flyback Converter Driving Capacitive Actuators

Yves Perriard, Alexis Boegli, Raphaël Johannes Charles Mottet

Dielectric Elastomer Actuators (DEAs) require ultra high voltages in the order of several kilo volts to operate. To supply such voltages, a DC-DC flyback converter topology was selected. One of the main advantage of using such a structure is the possibilit ...

IEEE2020

97.4%-Efficient All-GaN Dual-Active-Bridge Converter with High Step-up High-Frequency Matrix Transformer

Elison de Nazareth Matioli, Armin Jafari, Palliyage Srilak Nirmana Perera, Mohammad Samizadeh Nikooytabalvandani

In this work, we demonstrate a state-of-the-art high step-up/down dual-active-bridge (DAB) converter designed with GaN transistors, to achieve a high efficiency and large power-density. A quasi-planar matrix transformer with high step-up/down ratio is demo ...

2020

Reversible solid-oxide cell stack based power-to-x-to-power systems: Comparison of thermodynamic performance

François Maréchal, Jan Van Herle, Philippe Aubin, Ligang Wang, Maria del Mar Perez Fortes, Tzu-En Lin, Yumeng Zhang

The increasing penetration of variable renewable energies poses new challenges for grid management. The economic feasibility of grid-balancing plants may be limited by low annual operating hours if they work either only for power generation or only for pow ...

2020

Efficient High Step-up Operation in Boost Converters Based on Impulse Rectification

Elison de Nazareth Matioli, Armin Jafari, Palliyage Srilak Nirmana Perera

Conventional boost converters, while having a high level of simplicity and robustness, are known to have poor efficiency at high step-up regime. More complicated topologies have been extensively explored to increase the step-up ratio while keeping a high-e ...

2020

Pressure-induced transformation of CH3NH3PbI3: the role of the noble-gas pressure transmitting media

László Forró, Endre Horvath, Andrzej Sienkiewicz, Alla Arakcheeva, Gaétan Charles Antoine Giriat, Bálint Náfrádi, Márton Kollár, Anastasiia Glushkova

The photovoltaic perovskite, methylammonium lead triiodide [CH3NH3PbI3 (MAPbI(3))], is one of the most efficient materials for solar energy conversion. Various kinds of chemical and physical modifications have been applied to MAPbI(3) towards better unders ...

International Union of Crystallography (IUCr)2019

Efficiency vs. stability: dopant-free hole transporting materials towards stabilized perovskite solar cells

Mohammad Khaja Nazeeruddin, Kasparas Rakstys, Cansu Igci

In the last decade, perovskite solar cells have been considered a promising and burgeoning technology for solar energy conversion with a power conversion efficiency currently exceeding 24%. However, although perovskite solar cells have achieved high power ...

ROYAL SOC CHEMISTRY2019

Linking Morphology and Multi-Physical Transport in Structured Electrodes

Silvan Suter

Motivated to advance the renewable energy production and diversify the technologies for storable energy carriers, my work is concentrated on the characterization and the optimization of electrode morphologies applicable in photoelectrochemical water-splitt ...

EPFL2019

Laser shock peening: A promising tool for tailoring metallic microstructures in selective laser melting

Roland Logé, Ke Huang, Nikola Kalentics, Valerio Romano, Manuel Ortega Varela De Seijas, Andreas Burn

Metallic parts made by Selective Laser Melting (SLM) are known for their heterogeneous microstructures in the as-built (AB) state. In this paper, Laser Shock Peening (ISP) was performed on a 316 L stainless steel part fabricated by SLM. The LSP treatment i ...

2019

Strain generation and energy-conversion mechanisms in lead-based and lead-free piezoceramics

Dragan Damjanovic

Piezoelectric ceramics generate strain through the intrinsic piezoelectric effect, the motion of ferroelectric domain walls, or through field-induced phase transitions. The enhanced piezoelectric properties observed in morphotropic solid solutions arise fr ...

2018

Electric Charge Transfer Between Cascading Dielectric Electroactive Polymer Actuators

Yves Perriard, Alexis Boegli, Jonathan André Jean-Marie Chavanne, Raphaël Johannes Charles Mottet

With the never slowing interest in dielectric electroactive polymer (DEAP) actuators for medical applications, the need to optimize the management of the driving energy of these actuators becomes evermore important. In order to tackle the problematic of th ...

2018

Methodology for efficient use of thermal energy in the chemical and petrochemical industry

Elfie Marie Méchaussie

The current European energy regulation, aligned with the European Union energy strategy and targets for the next decade, requires large industrial companies to regularly assess their energy performance and implement energy efficiency improvement measures. ...

EPFL2018

Ultra-coherent nano-mechanical resonators for quantum optomechanics at room temperature

Amir Hossein Ghadimi

Mechanical oscillators are among the most important scientific tools in the modern physics. From the pioneering experiments in 18th by founding fathers of modern physics such as Newton, Hooke and Cavendish to the ground braking experiments in the 21th cent ...

EPFL2018

Electroadhesive device, system and method for gripping

Dario Floreano, Herbert Shea, Samuel Rosset, Jun Shintake, Bryan Edward Schubert

A device for electroadhesion and conversion of electrical energy into mechanical energy, for example electrostatic actuation, is provided, including a soft polymeric dielectric support having at least two sets of overlapping electrodes patterned respective ...

2017