Publications by Nestor Guijarro Carratala

Ink-Based CuIn0.3Ga0.7S2 Nanocrystal Thin Films as Photocathodes for Photoelectrochemical CO2 Reduction Reaction

Kevin Sivula, Jun Ho Yum, Nestor Guijarro Carratala

One of the promising methods to solve the current energyand environmentissues is photoelectrochemical (PEC) water splitting and CO2 reduction reaction. Chalcopyrite copper indium gallium sulfide (CIGS)and CuIn0.3Ga0.7S2 nanocrystal thinfilms have been cons ...

AMER CHEMICAL SOC2023

Photoelectrochemical CO2 Reduction at a Direct CuInGaS2/Electrolyte Junction

Michael Graetzel, Kevin Sivula, Jun Ho Yum, Meng Xia, Nestor Guijarro Carratala, Dan Ren, Yongpeng Liu, Simon Nussbaum

Photoelectrochemical (PEC) CO2 reduction has received considerable attention given the inherent sustainability and simplicity of directly converting solar energy into carbonbased chemical fuels. However, complex photocathode architectures with protecting l ...

AMER CHEMICAL SOC2023

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

Benzodithiophene‐Based Spacers for Layered and Quasi‐Layered Lead Halide Perovskite Solar Cells

Kevin Sivula, Jun Ho Yum, Mounir Driss Mensi, Liang Yao, Nestor Guijarro Carratala, Han-Hee Cho, Barbara Alexandra Primera Darwich, Luc Emile Monnier

Incorporating extended pi-conjugated organic cations in layered lead halide perovskites is a recent trend promising to merge the fields of organic semiconductors and lead halide perovskites. Herein, we integrate benzodithiophene (BDT) into Ruddlesden–Poppe ...

2021

Key factors boosting the performance of planar ZnFe2O4 photoanodes for solar water oxidation

Kevin Sivula, Nestor Guijarro Carratala, Yongpeng Liu, Florent Alexandre Boudoire

The performance of ZnFe2O4 photoanodes largely depends on their nanostructure, crystallinity and n-type doping, though decoupling their impact on photoactivity remains a challenge. Herein, the combined effects of the synthesis temperature and reductive ann ...

Royal Society of Chemistry2021

Spectroelectrochemical and Chemical Evidence of Surface Passivation at Zinc Ferrite (ZnFe 2 O 4 ) Photoanodes for Solar Water Oxidation

Michael Graetzel, Kevin Sivula, Mounir Driss Mensi, Meng Xia, Liang Yao, Nestor Guijarro Carratala, Dan Ren, Yongpeng Liu

Recent advances in low‐cost manufacturing as well as in bulk/interface engineering have positioned zinc ferrite (ZnFe2O4, ZFO) in the spotlight as a candidate material for solar water oxidation. However, the severe recombination at the reactive interface r ...

2021

A semiconducting polymer bulk heterojunction photoanode for solar water oxidation

Kevin Sivula, Jun Ho Yum, Liang Yao, Nestor Guijarro Carratala, Yongpeng Liu, Florent Alexandre Boudoire, Arvindh Sekar, Rebekah Anne Wells, Han-Hee Cho

Organic semiconductors hold promise to enable scalable, low-cost and high-performance artificial photosynthesis. However, the performance of systems based on organic semiconductors for light-driven water oxidation have remained poor compared with inorganic ...

NATURE RESEARCH2021

Spray Synthesis of CuFeO2 Photocathodes and In-Operando Assessment of Charge Carrier Recombination

Kevin Sivula, Nestor Guijarro Carratala, Florian Le Formal, Yongpeng Liu, Florent Alexandre Boudoire, Charles Roger Jean Lhermitte

Semiconducting delafossite-phase CuFeO2 is a promising photocathode material for solar-driven hydrogen production given its suitable energy levels and established robustness for photoelectrochemical water reduction. Nevertheless, reported methods for prepa ...

AMER CHEMICAL SOC2021

Identifying Reactive Sites and Surface Traps in Chalcopyrite Photocathodes

Michael Graetzel, Kevin Sivula, Mounir Driss Mensi, Meng Xia, Liang Yao, Nestor Guijarro Carratala, Yongpeng Liu

Gathering information on the atomic nature of reactive sites and trap states is key to fine tuning catalysis and suppressing deleterious surface voltage losses in photoelectrochemical technologies. Here, spectroelectrochemical and computational methods wer ...

Wiley-VCH Verlag GmbH2021

A Direct Z-Scheme for the Photocatalytic Hydrogen Production from a Water Ethanol Mixture on CoTiO3/TiO2 Heterostructures

Kevin Sivula, Liang Yao, Nestor Guijarro Carratala, Yongpeng Liu

Photocatalytic H-2 evolution from ethanol dehydrogenation is a convenient strategy to store solar energy in a highly valuable fuel with potential zero net CO2 balance. Herein, we report on the synthesis of CoTiO3/TiO2 composite catalysts with controlled am ...

AMER CHEMICAL SOC2021