KovalenkoLab

at ETHZ and Empa since 2011

[Maksym Kovalenko @maksymuki]

🧪 Our new ACS Materials Au Perspective explores soft organic dications for doping control in perovskite QDs.

✨ More than hopeful—we’re convinced tin-halide perovskite nanocrystals have a bright future as quantum-light sources!
📖 https://t.co/kE3NRZ9bMM

[Maksym Kovalenko @maksymuki]

💡 Keeping perovskite optical gain going means keeping heat under control.

New in Advanced Science: we investigate light amplification in thermally evaporated CsPbBr₃ films under long-pulse and continuous-wave excitation.

🔬 At 90 K, sapphire-supported films sustain amplified spontaneous emission with excitation pulses up to 30 µs, versus ~2 µs on glass—without encapsulation or post-processing.

🌡️ Heat accumulation emerges as the dominant limitation under extended excitation. Better heat extraction is essential for progress toward continuous-wave and electrically pumped perovskite lasers.

https://t.co/GfOOfoeIQl

[Maksym Kovalenko @maksymuki]

Thrilled to share our new paper in ACS Energy Letters! 🔋

We used Substrate-Enhanced Atomic Layer Deposition (ALD) to grow an ultra-thin, conformal Lithium Niobate layer on NMC cathodes. This protects the cathode and paves the way for safer, longer-lasting batteries! ⚡🔬

Read our work here 👇 https://t.co/LkJFD83PTM

[Maksym Kovalenko @maksymuki]

The surface chemistry of perovskite QDs is a cornerstone. Ligands play a highly complex role: progress requires understanding how they influence post-synthetic stability, and acknowledging that many are essential for the actual formation of these QDs 🧪.
​our new artixle in Chem. Sci. leverages this dynamic via A-site cation precursors:
​📏 Size control: Precursor tail length, rather than the headgroup, dictates the final QD size.
​🎯 Precision: Steric tuning enables exact sizes from 18 down to 3 nm.
​🚀 Efficiency: The approach yields up to a 40-fold increase compared to conventional routes.

Yuliia Berezovska , Dmitry Dirin et al.
https://t.co/BoAm1tAOeH

[Maksym Kovalenko @maksymuki]

🎉 Our latest research is out in Advanced Materials: "Single-Particle FRET Probes Heterogeneity in the Ligand Shell of Colloidal Perovskite Quantum Dots" by Leon Feld ( @FeldF ) et al.
One of our main research outputs in the scope of SNSF-sponsored NCCR Catalysis.

​We developed a method using single-particle photoluminescence spectroscopy to probe the notoriously difficult-to-characterize organic ligand shell of quantum dots (QDs) at the molecular scale, as well as to monitor FRET.

​✨ Key Takeaways:

​📏 We tagged ligand tails with dyes to measure ligand tail end-to-QD distances via FRET at sub-nanometer resolution.

​🔍 Revealed nanometer-scale variations in dye-surface distances within individual particles and across different ligand chemistries.

​💻 Linked these variations directly to local ligand coverage using atomistic modelling.

​📖 Read the full article: https://t.co/bnPlm8EFUf

[Maksym Kovalenko @maksymuki]

🔋 Does capacity always dictate a battery's potential? In our latest article in Accounts of Materials Research, we confront this assumption by focusing on a highly promising newcomer CAM (cathode active material): Lithium Iron Chloride (Li₂FeCl₄).

While Li₂FeCl₄ may have a lower theoretical capacity compared to traditional commercial materials, we demonstrate that it more than makes up for it with a critical advantage—⚡ exceptionally high ionic conductivity.

Why is this high conductivity so important?

🚀 Rapid ion transport drastically reduces internal resistance.

⚡ It significantly boosts overall kinetic and power performance.

🛠️ It opens exciting new, competitive pathways for fast-charging and all-solid-state battery applications.

Our research highlights that chasing maximum capacity isn't the only way to build better batteries; balancing kinetic properties is just as crucial. We firmly believe Li₂FeCl₄ is poised to be a strong contender in next-generation battery technologies.

Read our full findings here:
https://t.co/YlvsNtVWKF

[SCS Materials Chemistry @SCS_MatChem]

We are ready to open our International Summer School on Semiconductor Nanocrystals 2026 in < 2 h! The first participants have arrived and are enjoying the beautiful scenery right from the school's hotel! #nanocrystals26 https://t.co/TsgXkEU9kT @SwissChemistry @TracktheTwinQD

[Maksym Kovalenko @maksymuki]

Now time for poster abstracts submission! Don't miss your best conference

[Maksym Kovalenko @maksymuki]

A paper from collaboration with Prof. Eric Wachsman's group using our x-ray micro-computed tomography data.
https://t.co/z03YdPbRip

[Maksym Kovalenko @maksymuki]

🔬 What if we could watch photocatalysis happen—one catalyst at a time and in real time?

see our new article in Chem "Single-catalyst operando photoluminescence spectroscopy of perovskite quantum-dot-driven photoredox reactions"

We use an individual perovskite quantum dot simultaneously as:

✨ a quantum emitter
⚗️ a single photocatalyst
👁️ an operando probe of its own catalytic activity

Remarkably, these perovskite QDs are sufficiently robust to operate under realistic reaction conditions while revealing charge-transfer dynamics, particle-to-particle heterogeneity, and degradation at the few-atom level.

These insights are fundamentally inaccessible through conventional ensemble measurements

https://t.co/gt2KLwdcfe

[Maksym Kovalenko @maksymuki]

🔋 What if an electrolyte salt could become the energy-storing material?
In our new article, we show how lithium perchlorate (LiClO₄) can undergo an 8-electron reduction—unlocked through electrochemically coupled oxygen-atom transfer.
⚙️ Carbon-supported Fe nanoparticles play a double role: oxygen-transfer catalyst + conversion-type cathode material.
⚡ >50% LiClO₄ conversion
⚡ 1,150 mAh g⁻¹ capacity
⚡ 1,950 Wh kg⁻¹ (per kg of LiClO₄)
It is a proof of concept—not yet a practical battery—but it opens a new route toward harvesting the largely unexplored energy of p-block oxoanions.
Much inspired by discussions with Prof. Reinhard Nesper (ETH emeritus) over a decade ago.

https://t.co/W1AhsSoqOE

[KovalenkoLab @KovalenkoLab]

Collaboration led by Prof. Sohee Jeong, SKKU, South Korea.
https://t.co/RM9n9RpLY2

[Maksym Kovalenko @maksymuki]

Tin halide perovskite nanocrystals will have a bright future—once they have bright emission! ✨
​Our new paper in Advanced Materials outlines the essential first steps to get there:
❌ Stop attributing 2D-impurity PL to the nanocrystals.
❌ Eliminate those 2D impurities via amine-free synthesis.
✅ Start de-doping to manage intrinsic p-doping.
​Read our full findings here: https://t.co/LhEcySdmc4

[Maksym Kovalenko @maksymuki]

Dear Students, Postdocs, and Group Leaders, all who care for novel light-emitting materials. Your best conference of the year will take place in Halkidiki this September! This is the fifth edition.

EMLEM26-Emerging Light Emitting Materials
https://t.co/7rIgQTINQJ

General organization: @nanoGe_Conf

Scientific organizers: Maryna Bodnarchuk, Maksym Kovalenko

📍Halkidiki, Greece
🗓️21-23 September 2026

📅 Key dates to remember:
Oral abstract submission deadline: May 25, 2026
Poster abstract submission deadline: July 20, 2026

[Maksym Kovalenko @maksymuki]

We just published a paper on MAPbBr3 nanoplatelets with controlled edge length that sustain dilution to the single-particle level, along with the corresponding spectroscopy. These platelets are also integrated into optical cavities, thereby exhibiting strong light-matter interaction. A highly collaborative work, so thanks to each and every group involved!
@SekhTaras et al.
https://t.co/4uM8R0W50c

[Maksym Kovalenko @maksymuki]

from the wonderful collaboration with Will Tisdale's group.

https://t.co/3Z7LFYf6qC

[Maksym Kovalenko @maksymuki]

In this article, we present several important innovations in patterning perovksite layers, compatible with standard microfabrication methods and commonplace cleanrooms, including photolithography with water-based developers.
https://t.co/mcwxpjIWyM

[Maksym Kovalenko @maksymuki]

The fifth edition of our famous EMLEM conference this year, don't miss!

[Maksym Kovalenko @maksymuki]

Perovskite semiconductors CsPbX3 can simply be melt-cast in a conventional chemical laboratory, yielding inexpensive and excellent X-ray detector arrays.

https://t.co/83rojlQryt

[KovalenkoLab @KovalenkoLab]

Yan B. Vogel has lead this beautiful spectroelectrochemical study on ligand-engineered films of colloidal InAs quantum dots, showing electrochemical control of the electronic doping level.
https://t.co/ZKxVoVGCHP