Lichun Chang

Bio: Lichun Chang is an academic researcher from University of New South Wales. The author has contributed to research in topics: Organic solar cell & Finite element method. The author has an hindex of 2, co-authored 2 publications receiving 27 citations.

Optimising Non-Patterned MoO3/Ag/MoO3 Anode for High-Performance Semi-Transparent Organic Solar Cells towards Window Applications

Abstract: Semi-transparent organic solar cells (ST-OSCs) have attracted significant research attention, as they have strong potential to be applied in automobiles and buildings. For ST-OSCs, the transparent top electrode is an indispensable component, where the dielectric/metal/dielectric (D/M/D) structured electrode displayed a promising future due to its simplicity in the fabrication. In this work, by using the MoO3-/Ag-/MoO3-based D/M/D transparent electrode, we fabricated ST-OSCs based on the PM6:N3 active layer for the first time. In the device fabrication, the D/M/D transparent electrode was optimised by varying the thickness of the outer MoO3 layer. As a result, we found that increasing the thickness of the outer MoO3 layer can increase the average visible transmittance (AVT) but decrease the power conversion efficiency (PCE) of the device. The outer MoO3 layer with a 10 nm thickness was found as the optimum case, where its corresponding device showed the PCE of 9.18% with a high AVT of 28.94%. Moreover, the colour perception of fabricated ST-OSCs was investigated. All semi-transparent devices exhibited a neutral colour perception with a high colour rendering index (CRI) over 90, showing great potential for the window application.

Expanding the genetic variation of Brassica juncea by introgression of the Brassica rapa genome

Abstract: Abstract Brassica juncea is an important vegetable and oil crop cultivated worldwide. To increase its genetic variation, we introgressed the A genome of Brassica rapa into B. juncea. We used three each of heading and semi-heading B. juncea accessions as recipient parents and a B. rapa line, B9008, as the donor parent. We obtained 101 BC1S1 lines in total with expanded phenotypic variations such as leafy head shapes. We developed 132 single-nucleotide polymorphism (SNP) markers that could distinguish the A genome of B. juncea from the B. rapa genome, and tracked the introgression of B. rapa segments in the new B. juncea germplasm. On average, 59.2% of the B. juncea A genome in the B. juncea introgression lines was covered by the donor segments. We also identified three markers whose donor genotype frequencies were significantly lower than the theoretical value, suggesting strong selection of the recipient genotype during the introgression process. We provide an effective strategy to evaluate the diversity of the new germplasm based on the combination of parental resequencing data and marker genotyping results. Further genetic analysis of 1642 SNPs showed that the genetic diversity of the new B. juncea germplasm with the introgressed B. rapa genome was significantly increased. This study illustrates the potential for expanding the genetic diversity of B. juncea through the introgression of the B. rapa genome.

A Curved Plate-Flattening Method to Construct the Membrane Strain Distribution

Abstract: The surface-flattening process has many applications in industries such as shipbuilding. Curved surfaces in the industry are usually formed from flat surfaces, so the target surface needs to be flattened to obtain its corresponding initial shape. In addition, the surface flattening process obtains the inherent strain distribution required in forming. Different forming methods in the plate forming process will produce different membrane deformations, such as shrinkage in the line heating and tensile in the roller forming. Therefore, different surface-flattening methods should be used to obtain the inherent strain distribution suitable for different forming methods. This paper proposes a method to perform the surface flattening using the finite element method and constrain the membrane strain generated in the flattening deformation by modifying the material constitutive relationship. Using a dual modulus material constitutive model in membrane deformation makes the surface more inclined to deform at locations with less stiffness during the flattening process. This method yields predominantly tensile or compressive membrane strain without changing the bending strain. By modifying the material model, this method can control the compressive strain region and the principal strain direction. The results of the proposed method applying to different surface shapes and its application in the surface-forming process are given in this paper.

Transparent, near-infrared organic photovoltaic solar cells for window and energy-scavenging applications

Abstract: We fabricate near-infrared absorbing organic photovoltaics that are highly transparent to visible light. By optimizing near-infrared optical-interference, we demonstrate power efficiencies of 1.3±0.1% with simultaneous average visible transmission of >65%. Subsequent incorporation of near-infrared distributed-Bragg-reflector mirrors leads to an increase in the efficiency to 1.7±0.1%, approaching the 2.4±0.2% efficiency of the opaque cell, while maintaining high visible-transparency of >55%. Finally, we demonstrate that a series-integrated array of these transparent cells is capable of powering electronic devices under near-ambient lighting. This architecture suggests strategies for high-efficiency power-generating windows and highlights an application uniquely benefiting from excitonic electronics.