Polyiodide-assisted fabrication of hybrid perovskite thin films from lead nanolayers on flexible substrates

2022 ◽  
Author(s):  
Ivan Turkevych ◽  
Said KAZAOUI ◽  
Kouji Suemori ◽  
Alexey Tarasov ◽  
Eugene A. Goodilin ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Flexible Substrates ◽  
Iodine Vapor ◽  
Hybrid Perovskite ◽  
Remarkable Progress

Abstract Despite remarkable progress in solvent-assisted processing of hybrid perovskite thin films, the scalable fabrication of their uniform and pin-hole free layers remains a difficult task, especially on flexible substrates. In contrast, we have demonstrated that the polyiodide-assisted conversion of Pb nanolayers into MAPbI3 results in the formation of crystalline MAPbI3 thin films on large flexible substrates already at the room temperature. The exposure of stoichiometric Pb/MAI bilayers to iodine vapor leads to the formation of highly reactive polyiodide melts MAI3(L), which instantly react with the Pb nanolayers converting them into pure MAPbI3 films without byproducts or unreacted components.

scholarly journals Highly Sensitive InOxOzone Sensing Films on Flexible Substrates

2009 ◽  
Vol 2009 ◽  
pp. 1-5 ◽  
Author(s):  
G. Kiriakidis ◽  
K. Moschovis ◽  
I. Kortidis ◽  
R. Skarvelakis
Keyword(s):  
Thin Films ◽  
Gas Sensors ◽  
Air Conditioning ◽  
Room Temperature ◽  
Growth Conditions ◽  
Flexible Substrates ◽  
Dc Magnetron Sputtering ◽  
Surface Cracking ◽  
Highly Sensitive ◽  
Extended Surface

InOxthin films with a thickness of the order of 100 nm were grown by dc magnetron sputtering on glass, Si and flexible (PET) substrates. The electrical conductivity ofInOxthin films exhibited a change of two orders of magnitude during photoreduction with ultraviolet light and subsequent oxidation in ozone concentrations from 2370 to 15 ppb, at room temperature. Optical transparency of over 85% for all substrates was maintained. Film structural and ozone sensing properties were analyzed. Surface morphology investigations carried out by SEM for films on PET substrates showed extended surface cracking for bending angles beyond40∘. Optimization of growth conditions has led to films with extremely low detection levels for ozone down to 15 ppb at room temperature, demonstrating the wide prospective of utilizing these metal oxides as gas sensors on flexible substrates for a variety of automotive and air-conditioning applications.

Room-temperature crystallization of hybrid-perovskite thin films via solvent–solvent extraction for high-performance solar cells

2015 ◽  
Vol 3 (15) ◽  
pp. 8178-8184 ◽  
Author(s):  
Yuanyuan Zhou ◽  
Mengjin Yang ◽  
Wenwen Wu ◽  
Alexander L. Vasiliev ◽  
Kai Zhu ◽  
...  
Keyword(s):  
Thin Films ◽  
Solar Cells ◽  
Solvent Extraction ◽  
High Performance ◽  
Room Temperature ◽  
High Efficiency ◽  
Hybrid Perovskite ◽  
High Efficiency Solar Cells ◽  
Temperature Crystallization ◽  
Solvent Solvent

A simple one-step solvent-bathing process based on solvent–solvent extraction, is demonstrated for the controlled room-temperature crystallization of uniform, ultra-smooth hybrid-perovskite thin films for high-efficiency solar cells.

ROOM TEMPERATURE DEPOSITION OF SINGLE-WALLED CARBON NANOTUBE THIN FILMS

NANO ◽  
2010 ◽  
Vol 05 (05) ◽  
pp. 319-324
Author(s):  
SEUNG YOL JEONG ◽  
BHARVIN PAREKH ◽  
VARUN GUPTA ◽  
GIOVANNI FANCHINI ◽  
MANISH CHHOWALLA
Keyword(s):  
Thin Films ◽  
Carbon Nanotube ◽  
Room Temperature ◽  
Flexible Substrates ◽  
Simple Method ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Cold Zone ◽  
Coverage Density ◽  
Temperature Deposition

A simple method for direct deposition of single-walled carbon nanotube (SWNT) networks on flexible substrates at room temperature is reported. Deposition of thin films was carried out using a two-zone tube furnace where the nucleation and growth of SWNTs occur in vapor phase in the hot zone and condense onto substrates in the cold zone. Raman spectroscopy and scanning electron microscopy reveal individual, uniformly distributed SWNTs over large areas (several cm2). The coverage density of the SWNTs on flexible substrates can be controlled by the location of the substrates within the cold zone. The opto-electronic properties of the thin films indicated that they can be transparent and conducting with sheet resistances ranging from 4 to 21 kΩ/sq at corresponding transparencies of 51 to 87%, respectively.

Studies on Water in the Hydration Chamber of a Modified Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 544-545
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electron Microscope ◽  
Steady State ◽  
Room Temperature ◽  
Small Mass ◽  
Equilibrium Pressure ◽  
Biological Objects ◽  
Mechanical Pump ◽  
Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

Interactions Between Al and Cr Thin Films

1976 ◽  
Vol 34 ◽  
pp. 638-639
Author(s):  
R. M. Anderson ◽  
T. M. Reith ◽  
M. J. Sullivan ◽  
E. K. Brandis
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Vacuum System ◽  
Processing Temperature ◽  
Diffusion Couples ◽  
Electronic Circuits ◽  
Intermetallic Formation ◽  
Si Substrates ◽  
Aluminum Silicon

Thin films of aluminum or aluminum-silicon can be used in conjunction with thin films of chromium in integrated electronic circuits. For some applications, these films exhibit undesirable reactions; in particular, intermetallic formation below 500 C must be inhibited or prevented. The Al films, being the principal current carriers in interconnective metal applications, are usually much thicker than the Cr; so one might expect Al-rich intermetallics to form when the processing temperature goes out of control. Unfortunately, the JCPDS and the literature do not contain enough data on the Al-rich phases CrAl7 and Cr2Al11, and the determination of these data was a secondary aim of this work.To define a matrix of Cr-Al diffusion couples, Cr-Al films were deposited with two sets of variables: Al or Al-Si, and broken vacuum or single pumpdown. All films were deposited on 2-1/4-inch thermally oxidized Si substrates. A 500-Å layer of Cr was deposited at 120 Å/min on substrates at room temperature, in a vacuum system that had been pumped to 2 x 10-6 Torr. Then, with or without vacuum break, a 1000-Å layer of Al or Al-Si was deposited at 35 Å/s, with the substrates still at room temperature.

Investigation of ultra-thin films of YBa2Cu3O7−δ grown on MgO

1990 ◽  
Vol 48 (4) ◽  
pp. 6-7
Author(s):  
S.K. Streiffer ◽  
C.B. Eom ◽  
J.C. Bravman ◽  
T.H. Geballet
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Deposition Process ◽  
Nucleation And Growth ◽  
Multilayer Structures ◽  
Rf Power ◽  
Oxygen Loss ◽  
Transmission Electron ◽  
Single Target ◽  
Mtorr Argon

The study of very thin (<15 nm) YBa2Cu3O7−δ (YBCO) films is necessary both for investigating the nucleation and growth of films of this material and for achieving a better understanding of multilayer structures incorporating such thin YBCO regions. We have used transmission electron microscopy to examine ultra-thin films grown on MgO substrates by single-target, off-axis magnetron sputtering; details of the deposition process have been reported elsewhere. Briefly, polished MgO substrates were attached to a block placed at 90° to the sputtering target and heated to 650 °C. The sputtering was performed in 10 mtorr oxygen and 40 mtorr argon with an rf power of 125 watts. After deposition, the chamber was vented to 500 torr oxygen and allowed to cool to room temperature. Because of YBCO’s susceptibility to environmental degradation and oxygen loss, the technique of Xi, et al. was followed and a protective overlayer of amorphous YBCO was deposited on the just-grown films.

TEM sample preparation of wear-tested room-temperature pulsed-laser-deposited thin films of MoS2 by ultramicrotomy

1993 ◽  
Vol 51 ◽  
pp. 1118-1119
Author(s):  
Pamela F. Lloyd ◽  
Scott D. Walck
Keyword(s):  
Thin Films ◽  
Sample Preparation ◽  
Room Temperature ◽  
High Vacuum ◽  
Pulsed Laser ◽  
Ultra High Vacuum ◽  
Wear Testing ◽  
Preparation Technique ◽  
Cross Sectional ◽  
Aerospace Applications

Pulsed laser deposition (PLD) is a novel technique for the deposition of tribological thin films. MoS2 is the archetypical solid lubricant material for aerospace applications. It provides a low coefficient of friction from cryogenic temperatures to about 350°C and can be used in ultra high vacuum environments. The TEM is ideally suited for studying the microstructural and tribo-chemical changes that occur during wear. The normal cross sectional TEM sample preparation method does not work well because the material’s lubricity causes the sandwich to separate. Walck et al. deposited MoS2 through a mesh mask which gave suitable results for as-deposited films, but the discontinuous nature of the film is unsuitable for wear-testing. To investigate wear-tested, room temperature (RT) PLD MoS2 films, the sample preparation technique of Heuer and Howitt was adapted.Two 300 run thick films were deposited on single crystal NaCl substrates. One was wear-tested on a ball-on-disk tribometer using a 30 gm load at 150 rpm for one minute, and subsequently coated with a heavy layer of evaporated gold.

Interface motion during recrystallization of amorphous NiSi2

1990 ◽  
Vol 48 (4) ◽  
pp. 524-525
Author(s):  
J. L. Batstone ◽  
D.A. Smith
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Amorphous Film ◽  
Nucleation And Growth ◽  
Recrystallization Process ◽  
Amorphous Films ◽  
Interface Motion ◽  
Si Substrates ◽  
Spherical Caps ◽  
Crystal Interfaces

Recrystallization of amorphous NiSi2 involves nucleation and growth processes which can be studied dynamically in the electron microscope. Previous studies have shown thatCoSi2 recrystallises by nucleating spherical caps which then grow with a constant radial velocity. Coalescence results in the formation of hyperbolic grain boundaries. Nucleation of the isostructural NiSi2 results in small, approximately round grains with very rough amorphous/crystal interfaces. In this paper we show that the morphology of the rccrystallizcd film is dramatically affected by variations in the stoichiometry of the amorphous film.Thin films of NiSi2 were prepared by c-bcam deposition of Ni and Si onto Si3N4, windows supported by Si substrates at room temperature. The base pressure prior to deposition was 6 × 107 torr. In order to investigate the effect of stoichiomctry on the recrystallization process, the Ni/Si ratio was varied in the range NiSi1.8-2.4. The composition of the amorphous films was determined by Rutherford Backscattering.

STEM and ELS Observation of Early Oxide Formation on the Surface of Cr Thin Films

1980 ◽  
Vol 38 ◽  
pp. 412-413
Author(s):  
Fumio Watari ◽  
J. M. Cowley
Keyword(s):  
Thin Films ◽  
Optical System ◽  
Room Temperature ◽  
Oxide Formation ◽  
Initial Nucleation ◽  
Diffraction Patterns ◽  
Relationship Of ◽  
Multiple Twinning ◽  
Moderately High Temperature

STEM coupled with the optical system was used for the investigation of the early oxidation on the surface of Cr. Cr thin films (30 – 1000Å) were prepared by evaporation onto the polished or air-cleaved NaCl substrates at room temperature and 45°C in a vacuum of 10−6 Torr with an evaporation speed 0.3Å/sec. Rather thick specimens (200 – 1000Å) with various preferred orientations were used for the investigation of the oxidation at moderately high temperature (600 − 1100°C). Selected area diffraction patterns in these specimens are usually very much complicated by the existence of the different kinds of oxides and their multiple twinning. The determination of the epitaxial orientation relationship of the oxides formed on the Cr surface was made possible by intensive use of the optical system and microdiffraction techniques. Prior to the formation of the known rhombohedral Cr2O3, a thin spinel oxide, probably analogous to γ -Al203 or γ -Fe203, was formed. Fig. 1a shows the distinct epitaxial growth of the spinel (001) as well as the rhombohedral (125) on the well-oriented Cr(001) surface. In the case of the Cr specimen with the (001) preferred orientation (Fig. 1b), the rings explainable by spinel structure appeared as well as the well defined epitaxial spots of the spinel (001). The microdif fraction from 20A areas (Fig. 2a) clearly shows the same pattern as Fig. Ia with the weaker oxide spots among the more intense Cr spots, indicating that the thickness of the oxide is much less than that of Cr. The rhombohedral Cr2O3 was nucleated preferably at the Cr(011) sites provided by the polycrystalline nature of the present specimens with the relation Cr2O3 (001)//Cr(011), and by further oxidation it grew into full coverage of the rest of the Cr surface with the orientation determined by the initial nucleation.

Sign in / Sign up

Export Citation Format

Share Document