Jawaher Almutlaq

Massachusetts Institute of Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Omar F. Mohammed

King Abdullah University of Science and Technology

Ayan A. Zhumekenov

King Abdullah University of Science and Technology

Osman M. Bakr

King Abdullah University of Science and Technology

Raihana Begum

Nanyang Technological University

Jacob L. Swett

Arizona State University

Bolong Huang

Hong Kong Polytechnic University

Xinwei Guan

University of Newcastle Australia

İD

İbrahim Dursun

Cornell University

Huanghao Yang

Fuzhou University

Daniel Boon Loong Teh

National University of Singapore

Cooperative Institutions

King Abdullah University of Science and Technology

National University of Singapore

Oak Ridge National Laboratory

Shenzhen University

Nanyang Technological University

Fuzhou University

Center for Nanophase Materials Sciences

Chinese Academy of Sciences

Beijing Institute of Technology

University of Newcastle Australia

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Direct imaging of electron density with a scanning transmission electron microscope

Nature Communications (2023)

Ondrej Dyck Jawaher Almutlaq David B. Lingerfelt Jacob L. Swett Mark P. Oxley

Recent studies of secondary electron (SE) emission in scanning transmission electron microscopes suggest that material's properties such as electrical conductivity, connectivity, and work function can be probed with atomic scale resolution using a technique known as secondary electron e-beam-induced current (SEEBIC). Here, we apply the SEEBIC imaging technique to a stacked 2D heterostructure device to reveal the spatially resolved electron density of an encapsulated WSe2 layer. We find that the double Se lattice site shows higher emission than the W site, which is at odds with first-principles modelling of valence ionization of an isolated WSe2 cluster. These results illustrate that atomic level SEEBIC contrast within a single material is possible and that an enhanced understanding of atomic scale SE emission is required to account for the observed contrast. In turn, this suggests that, in the future, subtle information about interlayer bonding and the effect on electron orbitals could be directly revealed with this technique.

Atomic units

Valence electron

Secondary electrons

10.1038/s41467-023-42256-9

Cite

Citations (7)

All-inorganic perovskite nanocrystal scintillators

Nature (2018)

Qiushui Chen Jing Wu Xiangyu Ou Bolong Huang Jawaher Almutlaq

Radioluminescence

10.1038/s41586-018-0451-1

Cite

Citations (1,550)

Pure Cs₄PbBr₆: Highly Luminescent Zero-Dimensional Perovskite Solids

ACS Energy Letters (2016)

Makhsud I. Saidaminov Jawaher Almutlaq Smritakshi P. Sarmah İbrahim Dursun Ayan A. Zhumekenov

So-called zero-dimensional perovskites, such as Cs4PbBr6, promise outstanding emissive properties. However, Cs4PbBr6 is mostly prepared by melting of precursors that usually leads to a coformation of undesired phases. Here, we report a simple low-temperature solution-processed synthesis of pure Cs4PbBr6 with remarkable emission properties. We found that pure Cs4PbBr6 in solid form exhibits a 45% photoluminescence quantum yield (PLQY), in contrast to its three-dimensional counterpart, CsPbBr3, which exhibits more than 2 orders of magnitude lower PLQY. Such a PLQY of Cs4PbBr6 is significantly higher than that of other solid forms of lower-dimensional metal halide perovskite derivatives and perovskite nanocrystals. We attribute this dramatic increase in PL to the high exciton binding energy, which we estimate to be ∼353 meV, likely induced by the unique Bergerhoff–Schmitz–Dumont-type crystal structure of Cs4PbBr6, in which metal-halide-comprised octahedra are spatially confined. Our findings bring this class of perovskite derivatives to the forefront of color-converting and light-emitting applications.

Quantum yield

Crystal (programming language)

10.1021/acsenergylett.6b00396

Cite

Citations (529)