CsPbI2Br及びAgBiI4を光吸収層とする全無機太陽電池の界面及び組成のエンジニアリング

Recently, perovskite solar cells (PSCs) have got much attention due to their high efficiency and low-cost fabrication. Within the last ten years, they have shown a sharp rise in efficiency from an initial 3.8% to over 25.5% thus enabling them the most promising upcoming new generation solar cells. However, the bottom neck of PSCs lies in the prospect of commercialization, such as industry-standard stability and further reduction of manufacturing cost. Nevertheless, the perovskite film quality has a great influence on the working stability of the PSCs. Therefore, in this thesis, we focus to enhance the stability of perovskite-based devices by controlling the morphology and utilizing the interface passivation strategy. In addition, the toxic of lead is also a main problem of perovskite solar cells. The main research contents are as follows: In chapter 1, the development history of photovoltaic technology and the classification of solar cells have been introduced. In addition, the structure, working principle and the development of PSCs also been described, Moreover, lead-free solar cells and Ag-Bi-I ruddorfite solar cells also have presented. At the same time, the current challenges and the purpose of this thesis have been described. In chapter 2, we describe the fabrication of a carbon-based CsPbI2Br PSC. An Imidazolium-based ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4), was added to the CsPbI2Br perovskite film. The perovskite crystal quality and the device performance were improved. The results of SEM and XRD show that the additive of the ionic liquid can affect the perovskite nucleation and result in larger grain size. Furthermore, we also found that the addition of BMIMBF4 can reduce the energy barrier between the perovskite layer and carbon back electrode, which leads to better performance of PSCs. In chapter 3, in order to reduce the charge recombination, a simple surface passivation method with BMIMBF4 of CsPbI2Br was developed. The ionic liquid of BMIMBF4 as a modification layer can efficiently reduce the trap densities and inhibit non-radiative charge recombination, which made the efficiency up to 14%. We also observed that BMIMBF4 passivation can stabilize the CsPbI2Br phase at room temperature. In chapter 4, in order to explore non-toxicity and stable light-absorbing materials, we developed a Cs-incorporated AgBiI4 absorber, and the performance of this kind of rudorffite solar cells was improved due to the reducing trap-state density of AgBiI4 films and the efficient carrier transport. The Cs ion cooperated AgBiI4 exhibited an improvement of 40% in efficiency and better long-term stability than without Cs ion cooperation. In chapter 5, the conclusions and prospects are presented. Perovskite solar cells are facing significant challenges in terms of long-term stability and production costs. It would have great significance to further study the preparation of PSCs in the air environment.九州工業大学博士学位論文 学位記番号：生工博甲第411号 学位授与年月日：令和3年9月24日1. Introduction|2. Efficient Carbon-based CsPbI2BrPerovskite Solar Cell with Imidazolium-Based Ionic Liquid addition|3. Surface management for Carbon-based CsPbI2Br Perovskite Solar Cell with 14% Conversion Efficiency|4. Cs-incorporated AgBiI4 Rudorffite for Efficient and Stable Solar Cells九州工業大学令和3年

CsPbI2Br及びAgBiI4を光吸収層とする全無機太陽電池の界面及び組成のエンジニアリング

九州工業大学博士学位論文（要旨）学位記番号：生工博甲第411号 学位授与年月日：令和3年9月24

Over 23% power conversion efficiency of planar perovskite solar cells via bulk heterojunction design

The planar organic–inorganic hybrid perovskite solar cells (PSCs) have in recent years had remarkable success due to their superior optoelectronic performance. However, their power conversion efficiency is significantly inferior compared to mesoporous structure PSCs. Unlike most other advances focusing on non-perovskite materials to improve device performance, herein a multifunctional double perovskite material, Cs2PtI6, is proposed as the grain boundary modifier of organic–inorganic hybrid perovskite films. Results show three main benefits of introducing Cs2PtI6 into perovskite films: (1) it prompts growth of perovskite crystals, resulting in improved crystallinity and enlarged crystals; (2) it suppresses the trap assisted recombination at grain boundaries thanks to the formation of heterojunction and interface passivation; (3) it raises the efficiency of carrier collection and transport at grain boundaries owing to the high carrier mobility of Cs2PtI6. Consequently, a PCE of 23.56% is achieved. The unencapsulated devices show less than 10% degradation compared to the initial performance after storage in ambient (≈ 30%) humidity for 2000 h. This study outlines a simple yet effective strategy for boosting the performance of planar PSCs.journal articl

Case report: Circulating tumor DNA technology displays temporal and spatial heterogeneity in Waldenström macroglobulinemia during treatment with BTK inhibitors

Background: Waldenström macroglobulinemia (WM) is a rare subtype of B-cell lymphoma. Rituximab-based combination therapy and Bruton’s tyrosine kinase (BTK) inhibitors have greatly improved the prognosis of WM. Despite the high response rate and good tolerance of BTK inhibitors in treatment of WM, a proportion of patients still experience disease progression.Case presentation: We report a 55-year-old man with relapsed WM. The patient achieved partial remission after six courses of CHOP chemotherapy and multiple plasma exchanges in initial treatment. He was admitted to the hospital with abdominal distension, and was diagnosed with relapsed WM and subsequently started on zanubrutinib. Disease progression and histological transformation occurred during treatment. We performed liquid biopsies on transformed plasma, tumor tissue and ascites at the same time and found high consistency between ascites and tissues. Moreover, we detected resistance mutations of BTK inhibitors (BTK, PLCG2) in ascites that were not detected in plasma or tissue. Eventually, the patient died during the 15-month follow-up after relapse.Conclusion: We describe a rare case of WM transformation to DLCBCL treated with chemoimmunotherapy and BTK inhibition. We analyzed tumor DNA obtained at different anatomic sites and circulating tumor DNA (ctDNA) derived from plasma and ascites specimens, with apparent significant temporal and spatial heterogeneity. The case specifically highlights the clinical value of ctDNA of ascites supernatant from WM patients, which is a more convenient and relatively noninvasive method compared with traditional invasive tissue biopsy

An In-Situ Tester for Extracting Piezoresistive Coefficients

In this study, an electrostatic force-driven on-chip tester consisting of a mass with four guided cantilever beams was employed to extract the process-related bending stiffness and piezoresistive coefficient in-situ for the first time. The tester was manufactured using the standard bulk silicon piezoresistance process of Peking University, and was tested on-chip without additional handling. In order to reduce the deviation from process effects, the process-related bending stiffness was first extracted as an intermediate value, namely, 3590.74 N/m, which is 1.66% lower than the theoretical value. Then, the value was used to extract the piezoresistive coefficient using a finite element method (FEM) simulation. The extracted piezoresistive coefficient was 9.851 × 10−10 Pa−1, which essentially matched the average piezoresistive coefficient of the computational model based on the doping profile we first proposed. Compared with traditional extraction methods, such as the four-point bending method, this test method is on-chip, achieving automatic loading and precise control of the driving force, so it has high reliability and repeatability. Because the tester is manufactured together with the MEMS device, it has the potential to be used for process quality evaluation and monitoring on MEMS sensor production lines

Fabrication of a High-Quality Cu2ZnSn(S,Se)(4) Absorber Layer via an Aqueous Solution Process and Application in Solar Cells

The development of Cu2ZnSn(S,Se)(4) (CZTSSe) solar cells determines the prospect of thin-film photovoltaic devices because of some of their strengths. However, the usual solution fabrication processes of CZTSSe absorbing layers are either too tedious or highly toxic. Here, we have developed an alternative strategy to prepare kesterite CZTSSe absorber films with a simple and low-toxicity solution process by replacing the commonly employed thiol-based compounds using the glycolic acid aqueous solution, which significantly reduces the environment pollution and toxicity, providing a possibility toward the green solvent process. The power conversion efficiency of 6.81% has been acquired based the aqueous solution-processed CZTSSe thin film via optimizing the fabrication technology

A Multi-Criteria Evaluation of the Urban Ecological Environment in Shanghai Based on Remote Sensing

The urban ecological environment is related to human health and is one of the most concerned issues nowadays. Hence, it is essential to detect and then evaluate the urban ecological environment. However, the conventional manual detection methods have many limitations, such as the high cost of labor, time, and capital. The aim of this paper is to evaluate the urban ecological environment more conveniently and reasonably, thus this paper proposed an ecological environment evaluation method based on remote sensing and a projection pursuit model. Firstly, a series of criteria for the urban ecological environment in Shanghai City are obtained through remote sensing technology. Then, the ecological environment is comprehensively evaluated using the projection pursuit model. Lastly, the ecological environment changes of Shanghai City are analyzed. The results show that the average remote sensing ecological index of Shanghai in 2020 increased obviously compared with that in 2016. In addition, Jinshan District, Songjiang District, and Qingpu District have higher ecological environment quality, while Hongkou District, Jingan District, and Huangpu District have lower ecological environment quality. In addition, the ecological environment of all districts has a significant positive spatial autocorrelation. These findings suggest that the ecological environment of Shanghai has improved overall in the past five years. In addition, Hongkou District, Jingan District, and Huangpu District should put more effort into improving the ecological environment in future, and the improvement of ecological environment should consider the impact of surrounding districts. Moreover, the proposed weight setting method is more reasonable, and the proposed evaluation method is convenient and practical