Methylmagnesium Alkoxide Clusters with Mg4O4Cubane- and Mg7O8Biscubane-Like Cores: Organometallic Precursors for Low-Temperature Formation of MgO Nanoparticles with Variable Surface Defects

It is well known that electron transport layer (ETL) plays an indispensable role in the planar heterojunction perovskite solar cells (PSCs). TiO2 is widely used as an ETL material due to its excellent transport properties, however, the presence of defects in the TiO2 layer diminishes the power conversion efficiency (PCE) of the devices. Herein, we introduce a method of low-temperature TiCl4 treatment to deposit a TiOx layer on the surface of TiO2 film, which can effectively passivate trap states at the TiO2 surface. Moreover, the treating process is optimized to be 30[Formula: see text]min using a 40[Formula: see text]mM TiCl4 aqueous solution. Benefiting from this, we obtain the champion device with the highest PCE of 18.47%, which is mainly due to the reduction of surface defects and the deposition of the well-crystallized perovskite films. Besides, the modified PSCs exhibit an average PCE of 17.59%, which is much better than the control devices.

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Growth of Antimony Thin Films Using Perbenzylated Organometallic Precursors

MRS Proceedings ◽

10.1557/proc-547-481 ◽

1998 ◽

Vol 547 ◽

Cited By ~ 3

Author(s):

Michael P. Remington ◽

Smuruthi Kamepalli ◽

Philip Boudjouk ◽

Bryan R. Jarabek ◽

Dean G. Grier ◽

...

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Low Temperature ◽

Vapor Deposition ◽

Chemical Vapor ◽

Low Carbon ◽

Design Strategies ◽

Glass Substrates ◽

Pressure Chemical ◽

Organometallic Precursors

AbstractThe low temperature (ca. 300°C) deposition of antimony films by low-pressure chemical vapor deposition (LPCVD) on glass substrates from tribenzylantimony, Bn3Sb, is described. The facile elimination of the benzyl ligands results in preferentially oriented antimony films with low carbon content. The pyrolysis, decomposition mechanism and precursor design strategies are discussed. In addition, the deposition of bismuth from tribenzylbismuth, Bn3Bi, is presented. The potential for alloy growth using these precursors is discussed. Resulting films were characterized by XRD, SEM, and AFM.

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Superconducting fibers from organometallic precursors. Part II: Chemistry and low temperature processing1

Journal of Materials Research ◽

10.1557/jmr.1991.0895 ◽

1991 ◽

Vol 6 (5) ◽

pp. 895-907 ◽

Cited By ~ 13

Author(s):

Richard M. Laine ◽

Kay A. Youngdahl ◽

Richard A. Kennish ◽

Martin L. Hoppe ◽

Zhi-Fan Zhang ◽

...

Keyword(s):

Low Temperature ◽

Organometallic Polymers ◽

Metal Carboxylate ◽

Copper Metal ◽

Metal Carboxylates ◽

Yttrium Barium Cuprate ◽

Yttrium Barium ◽

Organometallic Precursors ◽

Optimal Approach ◽

Selection Of

Working principles are developed as guidelines for the selection and/or design of organometallic polymers for processing fiber precursors to metal oxide fibers. These principles form the basis for the selection of metal carboxylate preceramics as an optimal approach to processing yttrium barium cuprate (123) ceramic superconducting fibers. A variety of candidate yttrium, barium, calcium, strontium, bismuth, and copper metal carboxylates were synthesized. Solubility and empirical rheology tests were conducted to screen these compounds to choose spinnable precursor systems. Simple extrusion studies confirmed that THF solutions of mixtures of yttrium, barium, and copper isobutyrates with some quantity of barium 2-ethyl-hexanoates can be used to successfully form 60–70 μm diameter 123 precursor fibers.

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Excitons bound to surface defects in GaN

MRS Proceedings ◽

10.1557/proc-743-l11.3 ◽

2002 ◽

Vol 743 ◽

Cited By ~ 1

Author(s):

M. A. Reshchikov ◽

D. Huang ◽

H. Morkoç

Keyword(s):

Low Temperature ◽

Surface Defects ◽

Acceptor Pair ◽

Force Microscopy ◽

Uv Illumination ◽

Atomic Force ◽

Subsequent Exposure ◽

Donor Acceptor ◽

And Inversion ◽

Microscopy Images

ABSTRACTSharp intense peaks are sometimes detected in the low-temperature photoluminescence (PL) spectrum of undoped GaN samples in the photon energy range of 3.0 – 3.46 eV. Some of these peaks can be attributed to excitons bound to dislocations and inversion domains, whereas some others originate from the GaN surface because they can be affected essentially by surface treatment. In our samples, grown by molecular beam epitaxy on sapphire substrate, the 3.42 eV peak always disappeared after removing the surface layer by etching for a few seconds in hot phosphoric acid. Atomic force microscopy images confirmed that such light etching modifies the surface morphology, although the etched depth is negligibly small. Moreover, intensities of two other peaks (at 3.32 and 3.35 eV) were observed to depend on sample etching, as well as on the length of subsequent exposure to air. The 3.32 and 3.35 eV peaks evolved with time of UV illumination, increasing by several times and demonstrating memory effect at low temperature. We attribute the 3.42 and 3.35 eV peaks to bound excitons, whereas the 3.32 eV peak is tentatively attributed to a surface donor-acceptor pair transition.

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