Publications de Xiaoyun Yu | EPFL Graph Search

Solution-Processed Ultrathin SnS2-Pt Nanoplates for Photoelectrochemical Water Oxidation

Kevin Sivula, Xiaoyun Yu, Nestor Guijarro Carratala, Liang Yao, Yongpeng Liu, Yong Zuo, Ting Zhang

Tin disulfide (SnS2) is attracting significant interest because of the abundance of its elements and its excellent optoelectronic properties in part related to its layered structure. In this work, we specify the preparation of ultrathin SnS2 nanoplates (NP ...

AMER CHEMICAL SOC2019

Evaluating spinel ferrites MFe2O4 (M = Cu, Mg, Zn) as photoanodes for solar water oxidation: prospects and limitations

Kevin Sivula, Florian Le Formal, Pauline Bornoz, Xavier Adrian Jeanbourquin, Xiaoyun Yu, Mathieu Steven Prévot, Nestor Guijarro Carratala

2018

Catalyst-Free, Fast, and Tunable Synthesis for Robust Covalent Polymer Network Semiconducting Thin Films

Kevin Sivula, Xavier Adrian Jeanbourquin, Xiaoyun Yu, Nestor Guijarro Carratala, Arvindh Sekar, Liang Yao

2018

Defect Mitigation of Solution-Processed 2D WSe2 Nanoflakes for Solar-to-Hydrogen Conversion

Kevin Sivula, Xiaoyun Yu, Nestor Guijarro Carratala

Few-atomic-layer nanoflakes of liquid-phase exfoliated semiconducting transition metal dichalcogenides (TMDs) hold promise for large-area, high-performance, low-cost solar energy conversion, but their performance is limited by recombination at defect sites ...

American Chemical Society (ACS)2018

Photogenerated Charge Harvesting and Recombination in Photocathodes of Solvent-Exfoliated WSe2

Kevin Sivula, Xiaoyun Yu

Understanding and optimizing the effects of edge states and nanoflake dimensions on the photon harvesting efficiency in ultrathin transition-metal dichalcogenide (TMD) semiconductor photoelectrodes is critical to assessing their practical viability for sol ...

Amer Chemical Soc2017

Layered 2D semiconducting transition metal dichalcogenides for solar energy conversion

Kevin Sivula, Xiaoyun Yu

2017

Hybrid Heterojunctions of Solution-Processed Semiconducting 2D Transition Metal Dichalcogenides

Kevin Sivula, Xavier Adrian Jeanbourquin, Natalie Renuka Banerji, Xiaoyun Yu, Muhammad Aiman Bin Rahmanudin Hamdan, Nestor Guijarro Carratala

Exfoliated transition metal dichalcogenides (2D-TMDs) are attractive light-harvesting materials for large-area and inexpensive solar energy conversion given their ability to form highly tolerant heterojunctions. However, the preparation of large-area heter ...

Amer Chemical Soc2017

Engineering the self-assembly of diketopyrrolopyrrole-based molecular semiconductors via an aliphatic linker strategy

Kevin Sivula, Xavier Adrian Jeanbourquin, Andrea Gasperini, Xiaoyun Yu, Muhammad Aiman Bin Rahmanudin Hamdan, Nestor Guijarro Carratala, Emilie Aude Marie Ripaud

The solid-state self-assembly of molecular semiconductors is a key aspect for controlling the optoelectronic properties of organic electronic materials. Herein, we investigate the use of a flexible linker strategy to control the self-assembly of a solution ...

Royal Society of Chemistry2017

Amorphous Ternary Charge-Cascade Molecules for Bulk Heterojunction Photovoltaics

Kevin Sivula, Xavier Adrian Jeanbourquin, Xiaoyun Yu, Muhammad Aiman Bin Rahmanudin Hamdan, Nestor Guijarro Carratala, Liang Yao

Ternary bulk heterojunctions with cascade-type energy-level configurations are of significant interest for further improving the power conversion efficiency (PCE) of organic solar cells. However, controlling the self-assembly in solution-processed ternary ...

Amer Chemical Soc2017

Solution-processed two-dimensional transition metal dichalcogenides for solar energy conversion

Xiaoyun Yu

The layered semiconducting transition metal dichalcogenides (TMDs), such as MoS2, WS2, MoSe2, and WSe2, are promising light absorbers for solar energy conversion applications due to their superior optoelectronic properties and chemical stability, however s ...

EPFL2017

CuInGaS2 photocathodes treated with SbX3 (X = Cl, I): the effect of the halide on solar water splitting performance

Kevin Sivula, Florian Le Formal, Pauline Bornoz, Xavier Adrian Jeanbourquin, Wiktor Stefan Bourée, Xiaoyun Yu, Mathieu Steven Prévot, Nestor Guijarro Carratala

The realization of photoelectrochemical tandem cells for efficient solar-to-hydrogen energy conversion is currently impeded by the lack of inexpensive, stable, and efficient photocathodes. The family of sulfide chalcopyrites (CuInxGa1-xS2) has recently dem ...

Iop Publishing Ltd2017

The Role of Excitons and Free Charges in the Excited-State Dynamics of Solution-Processed Few-Layer MoS

Kevin Sivula, Natalie Renuka Banerji, Xiaoyun Yu

Solution-processed semiconducting transition metal dichalcogenides are emerging as promising two-dimensional materials for photovoltaic and optoelectronic applications. Here, we have used transient absorption spectroscopy to provide unambiguous evidence an ...

American Chemical Society2016

A Bottom-Up Approach toward All-Solution-Processed High-Efficiency Cu(In,Ga)S

Kevin Sivula, Florian Le Formal, Pauline Bornoz, Xavier Adrian Jeanbourquin, Wiktor Stefan Bourée, Xiaoyun Yu, Mathieu Steven Prévot, Nestor Guijarro Carratala

The development of solution-processable routes to prepare efficient photoelectrodes for water splitting is highly desirable to reduce manufacturing costs. Recently, sulfide chalcopyrites (Cu(In,Ga)S-2) have attracted attention as photocathodes for hydrogen ...

Wiley-VCH Verlag Berlin2016

Toward Large-Area Solar Energy Conversion with Semiconducting 2D Transition Metal Dichalcogenides

Kevin Sivula, Xiaoyun Yu

The recently discovered unique optoelectronic properties and chemical robustness of mono- or few-layer two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) such as MoS2, WS2, MoSe2, and WSe2 have opened new possibilities for solar en ...

Amer Chemical Soc2016

Direct Light-Driven Water Oxidation by a Ladder-Type Conjugated Polymer Photoanode

Kevin Sivula, Pauline Bornoz, Xiaoyun Yu, Mathieu Steven Prévot, Nestor Guijarro Carratala

A conjugated polymer known for high stability (poly[benzimidazobenzophenanthroline], coded as BBL) is examined as a photoanode for direct solar water oxidation. In aqueous electrolyte with a sacrificial hole acceptor (SO32-), photoelectrodes show a morphol ...

American Chemical Society2015

Autodecomposition Approach for the Low-Temperature Mesostructuring of Nanocrystal Semiconductor Electrodes

Kevin Sivula, Xavier Adrian Jeanbourquin, Xiaoyun Yu, Mathieu Steven Prévot, Nestor Guijarro Carratala

Templating nanocrystals into mesoporous electrodes using an organic porogen typically requires thermal oxidation at >400 degrees C to completely remove the organic material and afford good electronic properties. These oxidation conditions are incompatible ...

American Chemical Society2015

Self-assembled 2D WSe2 thin films for photoelectrochemical hydrogen production

Kevin Sivula, Xiaoyun Yu, Mathieu Steven Prévot, Nestor Guijarro Carratala

WSe2-a layered semiconductor that can be exfoliated into atomically thin two-dimensional sheets-offers promising characteristics for application in solar energy conversion. However, the lack of controllable, cost-effective methods to scalably fabricate hom ...

Nature Publishing Group2015

Multiflake Thin Film Electronic Devices of Solution Processed 2D MoS2

Kevin Sivula, Xiaoyun Yu, Mathieu Steven Prévot

Amer Chemical Soc2014