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Ivan A. Moreno-Hernandez

Ivan A. Moreno-Hernandez

Assistant Professor of Chemistry
Chemistry
ivan.moreno-hernandez@duke.edu
2214 French Science Center, Box 90346, Durham, NC 27708-0346
2214 French Science Center, 124 Science Drive, Durham, NC 27708-0236

Selected Publications

Understanding the reaction energetics of oxygen-evolving electrocatalysts

Journal Article Energy and Environmental Science · August 12, 2025 Electrocatalysts are crucial for efficient electrochemical devices that enable sustainable chemical transformations. Electrocatalyst activity has been correlated to the thermodynamics of reaction intermediates that balance intermediate formation and desorp ... Full text Cite

Oxidized Overlayers of Ruthenium and Iridium as Electrocatalysts for Anodic Reactions.

Journal Article Journal of the American Chemical Society · July 2025 Renewable energy technologies often rely on rutile tetravalent oxides, such as ruthenium(IV) oxide and iridium(IV) oxide, to catalyze anodic reactions that are paired with fuel formation. Herein, we report the synthesis of angstrom-scale and nanoscale oxid ... Full text Cite

Heterointercalation in Chevrel-Phase Sulfides: A Model Periodic Solid for the Investigation of Chain Electron Transfer.

Journal Article Journal of the American Chemical Society · May 2025 Modulation of electron density localization on periodic crystal solids through electron transfer from interstitial cations can directly influence the bonding configurations of small-molecule intermediates at the catalyst binding site. This study presents t ... Full text Cite

Understanding Electrochemical Degradation via Liquid Phase Transmission Electron Microscopy

Journal Article Journal of Physical Chemistry C · April 24, 2025 Electrochemical energy technologies will play a critical role in the worldwide transition to renewable energy. The fundamental electrochemical transformations that drive these technologies rely on materials that facilitate electron transfer at complex mate ... Full text Cite

Toward One-Way Smoke: Synthesis of Copper-Based Microclubs with Asymmetric Scattering and Absorption

Journal Article Advanced Functional Materials · July 17, 2024 The ultimate goal of this work is to create an engineered aerosol that acts as one-way smoke, i.e. it creates an asymmetric vision environment in which the ability to image objects depends on the viewing direction. To this end, a rapid, one-pot synthesis o ... Full text Cite

Dissolution Heterogeneity Observed in Anisotropic Ruthenium Dioxide Nanocrystals via Liquid-Phase Transmission Electron Microscopy.

Journal Article Journal of the American Chemical Society · April 2024 Noble metal oxides such as ruthenium dioxide are highly active electrocatalysts for anodic reactions in acidic electrolytes, but dissolution during electrochemical operation impedes wide-scale applications in renewable energy technologies. Improving the fu ... Full text Cite

EELS Studies of Cerium Electrolyte Reveal Substantial Solute Concentration Effects in Graphene Liquid Cells.

Journal Article Journal of the American Chemical Society · March 2023 Graphene liquid cell transmission electron microscopy is a powerful technique to visualize nanoscale dynamics and transformations at atomic resolution. However, the solution in liquid cells is known to be affected by radiolysis, and the stochastic formatio ... Full text Cite

Facet-selective etching trajectories of individual semiconductor nanocrystals.

Journal Article Science advances · August 2022 The size and shape of semiconductor nanocrystals govern their optical and electronic properties. Liquid cell transmission electron microscopy (LCTEM) is an emerging tool that can directly visualize nanoscale chemical transformations and therefore inform th ... Full text Cite

Recent advances in the study of colloidal nanocrystals enabled by in situ liquid-phase transmission electron microscopy

Journal Article MRS Bulletin · March 1, 2022 Liquid-phase transmission electron microscopy (LPTEM) has led to several advances in our understanding of nanoscale phenomena. However, the electron beam of the microscope, which allows visualization of the sample at the nanoscale, can itself interact with ... Full text Cite

Investigations of the stability of etched or platinized p-InP(100) photocathodes for solar-driven hydrogen evolution in acidic or alkaline aqueous electrolytes

Journal Article Energy and Environmental Science · November 1, 2021 The stability of p-InP photocathodes performing the hydrogen-evolution reaction (HER) has been evaluated in contact with either 1.0 M H2SO4(aq) or 1.0 M KOH(aq), with a focus on identifying corrosion mechanisms. Stability for the solar-driven HER was evalu ... Full text Cite

Elucidating the Role of Halides and Iron during Radiolysis-Driven Oxidative Etching of Gold Nanocrystals Using Liquid Cell Transmission Electron Microscopy and Pulse Radiolysis.

Journal Article Journal of the American Chemical Society · August 2021 Graphene liquid cell transmission electron microscopy (TEM) has enabled the observation of a variety of nanoscale transformations. Yet understanding the chemistry of the liquid cell solution and its impact on the observed transformations remains an importa ... Full text Cite

Redox Mediated Control of Electrochemical Potential in Liquid Cell Electron Microscopy.

Journal Article Journal of the American Chemical Society · August 2021 Liquid cell electron microscopy enables the study of nanoscale transformations in solvents with high spatial and temporal resolution, but for the technique to achieve its potential requires a new level of control over the reactivity caused by radical gener ... Full text Cite

AutoDetect-mNP: An Unsupervised Machine Learning Algorithm for Automated Analysis of Transmission Electron Microscope Images of Metal Nanoparticles.

Journal Article JACS Au · March 2021 The synthesis quality of artificial inorganic nanocrystals is most often assessed by transmission electron microscopy (TEM) for which high-throughput advances have dramatically increased both the quantity and information richness of metal nanoparticle (mNP ... Full text Cite

In Situ Quantification of Interactions between Charged Nanorods in a Predefined Potential Energy Landscape.

Journal Article Nano letters · January 2021 Quantitative understanding of nanoscale interactions is a prerequisite for harnessing the remarkable collective properties of nanoparticle systems. Here, we report the combined use of liquid-phase transmission electron microscopy and electron beam lithogra ... Full text Cite

Precise Colloidal Plasmonic Photocatalysts Constructed by Multistep Photodepositions.

Journal Article Nano letters · December 2020 Natural photosynthesis relies on a sophisticated charge transfer pathway among multiple components with precise spatial, energetic, and temporal organizations in the aqueous environment. It continues to inspire and challenge the design and fabrication of a ... Full text Cite

Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte

Journal Article Energy and Environmental Science · November 1, 2020 Alkaline electrolytes impede the corrosion of Si photoanodes under positive potentials and/or illumination, due to the formation of a SiOx layer that etches 2-3 orders of magnitude more slowly than Si. Hence during water oxidation under illumination, pinho ... Full text Cite

Self-Limiting Shell Formation in Cu@Ag Core-Shell Nanocrystals during Galvanic Replacement.

Journal Article The journal of physical chemistry letters · July 2020 The understanding of synthetic pathways of bimetallic nanocrystals remains limited due to the complex energy landscapes and dynamics involved. In this work, we investigate the formation of self-limiting Cu@Ag core-shell nanoparticles starting from Cu nanoc ... Full text Cite

Conformal SnO: X heterojunction coatings for stabilized photoelectrochemical water oxidation using arrays of silicon microcones

Journal Article Journal of Materials Chemistry A · May 14, 2020 The efficiency of photoelectrodes towards fuel-forming reactions is strongly affected by surface-based charge recombination, charge-transfer losses, and parasitic light absorption by electrocatalysts. We report a protective tin oxide (SnOx) laye ... Full text Cite

Crystalline nickel, cobalt, and manganese antimonates as electrocatalysts for the chlorine evolution reaction

Journal Article Energy and Environmental Science · April 1, 2019 The chlorine-evolution reaction (CER) is a common, commercially valuable electrochemical reaction, and is practiced at industrial scale globally. A precious metal solid solution of RuO2 or IrO2 with TiO2 is the predominant ... Full text Cite

Tin Oxide as a Protective Heterojunction with Silicon for Efficient Photoelectrochemical Water Oxidation in Strongly Acidic or Alkaline Electrolytes

Journal Article Advanced Energy Materials · August 27, 2018 Photoelectrodes without a p–n junction are often limited in efficiency by charge recombination at semiconductor surfaces and slow charge transfer to electrocatalysts. This study reports that tin oxide (SnOx) layers applied to n-Si wafers after f ... Full text Cite

Performance and failure modes of Si anodes patterned with thin-film Ni catalyst islands for water oxidation

Journal Article Sustainable Energy and Fuels · January 1, 2018 Silicon photoanodes patterned with thin-film Ni catalyst islands exhibited stable oxygen evolution for over 240 h of continuous operation in 1.0 mol L-1 KOH under simulated sunlight conditions. Buried-junction np+-Si(111) photoanodes ... Full text Cite

Crystalline nickel manganese antimonate as a stable water-oxidation catalyst in aqueous 1.0 M H2SO4

Journal Article Energy and Environmental Science · October 1, 2017 Water oxidation is a required half-reaction for electrochemical water splitting. To date, the only well-established active oxygen-evolution catalysts stable under operating conditions and at rest in acidic aqueous media contain Ru or Ir, two of the scarces ... Full text Cite

Photoelectrochemical Behavior of a Molecular Ru-Based Water-Oxidation Catalyst Bound to TiO2-Protected Si Photoanodes.

Journal Article Journal of the American Chemical Society · August 2017 A hybrid photoanode based on a molecular water oxidation precatalyst was prepared from TiO2-protected n- or p+-Si coated with multiwalled carbon nanotubes (CNT) and the ruthenium-based water oxidation precatalyst [RuIV(tda) ... Full text Cite

A comparison of the chemical, optical and electrocatalytic properties of water-oxidation catalysts for use in integrated solar-fuel generators

Journal Article Energy and Environmental Science · April 1, 2017 The in situ optical properties and electrocatalytic performance of representative catalysts for the oxygen-evolution reaction (OER) have been considered together to evaluate system-level effects that accompany the integration of OER catalysts into a solar- ... Full text Cite