Optical Transitions in Organic and Inorganic Semiconductors

2017 ◽  
pp. 43-70
Author(s):  
Juan Bisquert
1971 ◽  
Vol 32 (C1) ◽  
pp. C1-932-C1-933 ◽  
Author(s):  
H. W. LEHMANN ◽  
G. HARBEKE ◽  
H. PINCH

1984 ◽  
Vol 45 (C8) ◽  
pp. C8-57-C8-60 ◽  
Author(s):  
M. Hanfland ◽  
K. Syassen ◽  
N. E. Christensen

Author(s):  
Shuangjun Li ◽  
Linglong Chen ◽  
Zhong Ma ◽  
Guisheng Li ◽  
Dieqing Zhang

AbstractThe emission of nitrogen oxides (NOx) increases year by year, causing serious problems to our livelihoods. The photocatalytic oxidation of NOx has attracted more attention recently because of its efficient removal of NOx, especially for low concentrations of NOx. In this review, the mechanism of the photocatalytic oxidation of NOx is described. Then, the recent progress on the development of photocatalysts is reviewed according to the categories of inorganic semiconductors, bismuth-based compounds, nitrogen carbide polymer, and metal organic frameworks (MOFs). In addition, the photoelectrocatalytic oxidation of NOx, a method involving the application of an external voltage on the photocatalytic system to further increase the removal efficiency of NOx, and its progress are summarized. Finally, we outline the remaining challenges and provide our perspectives on the future directions for the photocatalytic oxidation of NOx.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shalini Menezes ◽  
Anura P. Samantilleke ◽  
Bryon W. Larson

AbstractPairing semiconductors with electrochemical processing offers an untapped opportunity to create novel nanostructures for practical devices. Here we report the results of one such pairing: the in-situ formation of highly-doped, interface-matched, sharp nanocrystalline homojunctions (NHJs) with single step electrodeposition of two copper-indium-selenide (CISe) compounds on flexible foil. It produces a homogenous film, comprising inherently ordered, 3-dimensional interconnected network of pn-CISe NHJs. These CISe NHJs exhibit surprising non-linear emissions, quantized transitions, large carrier mobility, low trap-state-density, long carrier lifetime and possible up-conversion. They facilitate efficient separation of minority carriers, reduce recombination and essentially function like quantum materials. This approach mitigates the material issues and complex fabrication of incumbent nanoscale heterojunctions; it also overcomes the flexibility and scale-up challenges of conventional planar pn junctions. The self-stabilized CISe NHJ film can be roll-to-roll processed in ambient atmosphere, thus providing a promising platform for a range of optoelectronic technologies. This concept exemplified by CISe compounds can be adapted to create nano-scale pn junctions with other inorganic semiconductors.


2021 ◽  
Vol 271 ◽  
pp. 115238
Author(s):  
Rihani Jawher ◽  
Radhwen Chtourou ◽  
Vincent Sallet ◽  
Mehrez Oueslati

Microscopy ◽  
2020 ◽  
Author(s):  
Kazuo Yamamoto ◽  
Satoshi Anada ◽  
Takeshi Sato ◽  
Noriyuki Yoshimoto ◽  
Tsukasa Hirayama

Abstract Phase-shifting electron holography (PS-EH) is an interference transmission electron microscopy technique that accurately visualizes potential distributions in functional materials, such as semiconductors. In this paper, we briefly introduce the features of the PS-EH that overcome some of the issues facing the conventional EH based on Fourier transformation. Then, we present a high-precision PS-EH technique with multiple electron biprisms and a sample preparation technique using a cryo-focused-ion-beam, which are important techniques for the accurate phase measurement of semiconductors. We present several applications of PS-EH to demonstrate the potential in organic and inorganic semiconductors and then discuss the differences by comparing them with previous reports on the conventional EH. We show that in situ biasing PS-EH was able to observe not only electric potential distribution but also electric field and charge density at a GaAs p-n junction and clarify how local band structures, depletion layer widths, and space charges changed depending on the biasing conditions. Moreover, the PS-EH clearly visualized the local potential distributions of two-dimensional electron gas (2DEG) layers formed at AlGaN/GaN interfaces with different Al compositions. We also report the results of our PS-EH application for organic electroluminescence (OEL) multilayers and point out the significant potential changes in the layers. The proposed PS-EH enables more precise phase measurement compared to the conventional EH, and our findings introduced in this paper will contribute to the future research and development of high-performance semiconductor materials and devices.


Sign in / Sign up

Export Citation Format

Share Document