About

Moungi Bawendi is the Lester Wolfe Professor of Chemistry at MIT and an advisor for the Minor in Energy Studies within the MIT Energy Initiative. His research focuses on the science and applications of nanocrystals, particularly semiconductor nanocrystals, also known as quantum dots. His lab's work spans from fundamental studies to practical applications in electro-optics and biology, involving the synthesis of new nanocrystal compositions, morphologies, and heterostructures, as well as the development of new ligands for integration into hybrid organic/inorganic devices and biological systems. The fundamental spectroscopic research conducted by his group primarily investigates the electronic structure dynamics of individual quantum dots at timescales between 100 picoseconds and 1 millisecond. The group also explores the physics of multiexcitons in quantum dots using ensemble and single-dot spectroscopic methods. Additionally, his lab studies charge transport properties of films of nanocrystals and hybrid systems, which are critical for designing devices such as quantum dot-based light emitters, lasers, photodetectors, and photovoltaics. On the biomedical front, his team collaborates with biology and medical groups to design nanocrystal probes for applications like receptor tracking, analyte sensing, and in vivo molecular imaging, focusing on how size, morphology, charge, and surface composition influence nanocrystal uptake and clearance.

Research topics

• Materials science
• Computer Science
• Nanotechnology
• Optoelectronics
• Physics
• Machine Learning
• Chemistry
• Optics
• Condensed matter physics
• Electrical engineering
• Artificial Intelligence
• Inorganic chemistry
• Engineering physics
• Molecular physics
• Physical chemistry
• Engineering
• Crystallography
• Organic chemistry
• Computational physics
• Quantum mechanics
• Biology
• Psychology
• Chemical engineering
• Telecommunications

Selected publications

• Ambient-compatible precursor engineering for efficient perovskite photovoltaics

  Nature Communications · 2026-04-22

  articleOpen access

  Achieving high-efficiency perovskite solar cells (PSCs) under ambient conditions remains a critical bottleneck for commercialization, primarily owing to the strong susceptibility of perovskite precursors and film formation processes to moisture and oxygen. Here, we develop a robust air-processing strategy for inverted PSCs by incorporating 1-butyl-3-methylimidazolium trifluoroacetate (BMIT) into precursor solutions, resulting in enhanced environmental tolerance of perovskite precursors by inhibiting iodide oxidation and facilitating stable film formation across a wide humidity range (20–60%). Moreover, the balanced ionic coordination suppresses Pb-I aggregation, mitigates colloidal clustering, and modulates nucleation kinetics, resulting in dense, highly crystalline perovskite films with excellent reproducibility. Consequently, we demonstrate high-efficiency devices across varied bandgaps (1.51, 1.54, and 1.68 eV), including a certified power conversion efficiency (PCE) of 26.48% with a fill factor of up to 85.00% for the 1.54-eV cell. Our device retains 96% of its initial PCE after 1,400 h of continuous 1-sun operation in ambient air. Perovskite solar cells face efficiency losses in ambient air because their precursors are highly moisture- and oxygen-sensitive. Liu et al. use an ionic-liquid additive to stabilize precursor chemistry, enabling robust processing and high-performance devices.

  PublisherDOI

• Single-Emitter Spectra from an Ensemble

  ArXiv.org · 2026-02-02

  articleOpen accessSenior author

  The heterogeneity in nanoscale emitters hinders efforts to understand their basic photophysics and limits their use in practical applications. Existing methods have difficulty accurately characterizing single-emitter spectra and optical heterogeneity on a statistical scale. Here, we introduce SPICEE (SPectrally Imbalanced Correlations from Ensemble Emission), a spectrally filtered photon-correlation technique that recovers single-particle emission lineshapes from an ensemble sample. Analytical derivations, numerical modeling, and experiments on a solution ensemble of emitters validate the technique. We apply SPICEE to blue-emitting ZnSeTe semiconductor nanocrystals relevant to display applications and find that the low color purity in the ensemble spectrum is primarily caused by a small subpopulation of nanocrystals with a distinct emission mechanism. This work demonstrates that SPICEE is a powerful high-throughput tool for accurately characterizing the single-emitter properties of nanoscale systems.

  PublisherOA PDF

• Single-Emitter Spectra from an Ensemble

  Open MIND · 2026-02-02

  preprintSenior author

  The heterogeneity in nanoscale emitters hinders efforts to understand their basic photophysics and limits their use in practical applications. Existing methods have difficulty accurately characterizing single-emitter spectra and optical heterogeneity on a statistical scale. Here, we introduce SPICEE (SPectrally Imbalanced Correlations from Ensemble Emission), a spectrally filtered photon-correlation technique that recovers single-particle emission lineshapes from an ensemble sample. Analytical derivations, numerical modeling, and experiments on a solution ensemble of emitters validate the technique. We apply SPICEE to blue-emitting ZnSeTe semiconductor nanocrystals relevant to display applications and find that the low color purity in the ensemble spectrum is primarily caused by a small subpopulation of nanocrystals with a distinct emission mechanism. This work demonstrates that SPICEE is a powerful high-throughput tool for accurately characterizing the single-emitter properties of nanoscale systems.

  DOI

• Overcoming the surface paradox: Buried perovskite quantum dots in wide-bandgap perovskite thin films

  arXiv (Cornell University) · 2025-01-10 · 1 citations

  preprintOpen access

  Colloidal perovskite quantum dots (PQDs) are an exciting platform for on-demand quantum, and classical optoelectronic and photonic devices. However, their potential success is limited by the extreme sensitivity and low stability arising from their weak intrinsic lattice bond energy and complex surface chemistry. Here we report a novel platform of buried perovskite quantum dots (b-PQDs) in a three-dimensional perovskite thin-film, fabricated using one-step, flash annealing, which overcomes surface related instabilities in colloidal perovskite dots. The b-PQDs demonstrate ultrabright and stable single-dot emission, with resolution-limited linewidths below 130 μeV, photon-antibunching (g^2(0)=0.1), no blinking, suppressed spectral diffusion, and high photon count rates of 10^4/s, consistent with unity quantum yield. The ultrasharp linewidth resolves exciton fine-structures (dark and triplet excitons) and their dynamics under a magnetic field. Additionally, b-PQDs can be electrically driven to emit single photons with 1 meV linewidth and photon-antibunching (g^2(0)=0.4). These results pave the way for on-chip, low-cost single-photon sources for next generation quantum optical communication and sensing.

  PublisherOA PDFDOI

• A 2D/3D Heterostructure Perovskite Solar Cell with a Phase‐Pure and Pristine 2D Layer

  Advanced Materials · 2025-03-18 · 22 citations

  articleOpen accessSenior authorCorresponding

  Abstract Interface engineering plays a critical role in advancing the performance of perovskite solar cells. As such, 2D/3D perovskite heterostructures are of particular interest due to their optoelectrical properties and their further potential improvements. However, for conventional solution‐processed 2D perovskites grown on an underlying 3D perovskite, the reaction stoichiometry is normally unbalanced with excess precursors. Moreover, the formed 2D perovskite is impure, leading to unfavorable energy band alignment at the interface. Here a simple method is presented that solves both issues simultaneously. The 2D formation reaction is taken first to completion, fully consuming excess PbI 2 . Then, isopropanol is utilized to remove excess organic ligands, control the 2D perovskite thickness, and obtain a phase‐pure, n = 2, 2D perovskite. The outcome is a pristine (without residual 2D precursors) and phase‐pure 2D perovskite heterostructure with improved surface passivation and charge carrier extraction compared to the conventional solution process. PSCs incorporating this treatment demonstrate a notable improvement in both stability and power conversion efficiency, with negligible hysteresis, compared to the conventional process.

  PublisherOA PDFDOI

• Oxygen vacancy formation in ZnSeTe blue quantum dot light-emitting diodes

  ArXiv.org · 2025-09-16

  preprintOpen accessSenior author

  Recent advancements have led to the development of bright and heavy metal-free blue-emitting quantum dot light-emitting diodes (QLEDs). However, consensus understanding of their distinct photophysical and electroluminescent dynamics remains elusive. This work correlates the chemical and electronic changes occurring in a QLED during operation using depth-resolved and operando techniques. The results indicate that oxygen vacancy forms in the ZnMgO layer during operation, with important implications on the charge injection and electrochemical dynamics. Taken together, the results suggest a causal relationship between oxygen vacancy formation and operational degradation of the blue-emitting ZnSeTe-based QLEDs.

  PublisherOA PDFDOI

• Morphological and Chemical Changes in Cd-free Colloidal QD-LEDs During Operation

  ArXiv.org · 2025-09-16

  preprintOpen access

  Heavy metal-free quantum-dot light-emitting devices (QD-LEDs) have demonstrated remarkable brightness, saturated color, and high efficiencies across a broad spectral range. However, in contrast to organic LEDs (OLEDs), QD-LED operational lifetimes remain limited, with the underlying degradation mechanisms not fully understood. In the present study, we show that InP/ZnSe/ZnS (red-emitting) and ZnTeSe/ZnSe/ZnS (blue-emitting) cadmium-free colloidal QD-LEDs undergo nanoscale morphological changes during operation. Specifically,interparticle coarsening and layer thinning are observed in the electron transport layer (ETL) consisting of ZnMgO nanoparticles (NPs), in the QD emissive layer, and in the organic hole transport layer. This is accompanied by the generation and diffusion of compositional oxygen- and hydrogen-radicals throughout the device, with oxygen accumulating at the electrode/ETL interfance. Moreover, in situ transmission electron microscopy reveals the electron beam exposure, in the presence of hydrogen radicals, accelerates ZnMgO NPs coarsening. To mitigate these degradation pathway, we show that acrylate-based resin-encapsulation treatment stabilize the ETL/QD layers by suppressing the radical formation and halting morphology changes. This approach achieves dramatic stability enhancements, exhibits an 8-fold and 5000-fold lifetime improvement on InP/ZnSe/ZnS and ZnTeSe/ZnSe/ZnS QD-LEDs, respectively. Our findings establish the causal relationships between the morphological degradation, interlayer radical dynamics, and state-of-the-art QD-LEDs instability, providing new insights into a scalable encapsulation treatment that enables efficient and long-lived Cd-free QD-LEDs.

  PublisherOA PDFDOI

• Deactivation of Interfacial Recombination Center for Thermally Stable Perovskite Solar Cells

  Journal of the American Chemical Society · 2025-10-01 · 5 citations

  article

  from 1.032 to 1.19 V after introducing APTES, along with a certified PCE of 25.6%. Thermal stability tests at 85 °C for 1000 h following the ISOS-D2I protocol show that 82% of the initial PCE is retained by the deactivation approach.

  PublisherDOI

• Nontoxic and Rapid Chemical Bath Deposition for SnO₂ Electron Transporting Layers in Perovskite Solar Cells

  Chemistry of Materials · 2025-07-18 · 2 citations

  articleSenior authorCorresponding

  Perovskite solar cells are a promising solar technology with efficiencies surpassing polycrystalline silicon solar cell technology. For the n-i-p perovskite solar cells, tin oxide is typically used as the electron transport layer. One typical deposition method is chemical bath deposition. However, the drawbacks are toxic precursors and the slow reaction driven by dissolved oxygen forming SnO2–x. Here, we present a tin oxide chemical bath deposition starting from nontoxic sodium stannate solutions. Within 6 min of reaction time, a 9 nm thick amorphous Sn(IV) oxide film is grown, yielding solar cells with power conversion efficiencies of at least 23.2%. Surprisingly, the sole use of Sn(IV) precursors contradicts the previous assumption on Sn(II) required for n-doping and high electric conductivity, and, unexpectedly, amorphous tin oxide films are as suitable for charge transport layers as their crystalline counterparts. The synthesis method is transferrable to other substrates (ITO, glass) and beneficial for devices such as solar cells, photodetectors, light-emitting diodes, and heterogeneous catalysis.

  PublisherDOI

• DNA origami directed nanometer-scale integration of colloidal quantum emitters with silicon photonics

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-01-26 · 1 citations

  preprintOpen access

  Abstract Incorporation of colloidal quantum emitters into silicon-based photonic devices would enable major advances in quantum optics. However, deterministic placement of individual sub-10 nm colloidal particles onto micron-sized photonic structures with nanometer-scale precision remains an outstanding challenge. Here, we introduce Cavity-Shape Modulated Origami Placement (CSMOP) that leverages the structural programmability of DNA origami to precisely deposit colloidal nanomaterials within lithographically-defined resist cavities. CSMOP enables clean and accurate patterning of origami templates onto photonic chips with high yields. Soft-silicification-passivation stabilizes deposited origamis, while preserving their binding sites to attach and align colloidal quantum rods (QRs) to control their nanoscale positions and emission polarization. We demonstrate QR integration with photonic device structures including waveguides, micro-ring resonators, and bullseye photonic cavities. CSMOP therefore offers a general platform for the integration of colloidal quantum materials into photonic circuits, with broad potential to empower quantum science and technology.

  PublisherOA PDFDOI

Recent grants

• Designing Bright and Fast Fluorophores with Large Stokes' Shifts Based on Superradiant Molecular J-Aggregates

  NSF · $480k · 2021–2024

• Scalable Quantum Emitters Enabled through Rational Bottom-Up Synthesis

  NSF · $480k · 2019–2022

Frequent coauthors

• Vladimir Bulović

  Massachusetts Institute of Technology

  133 shared

• Rakesh K. Jain

  109 shared

• Dai Fukumura

  92 shared

• Hedi Mattoussi

  Florida State University

  66 shared

• Klavs F. Jensen

  Massachusetts Institute of Technology

  64 shared

• Daniel G. Nocera

  50 shared

• John V. Frangioni

  Beth Israel Deaconess Medical Center

  48 shared

• John P. Zimmer

  48 shared

Labs

• The Bawendi LabPI