| 1. |
- Meng, Qijun, 1990-, et al.
(författare)
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Integrating Cobalt-sites-rich Aza-fused Conjugated Microporous Polymers on BiVO4 for Efficient Photoelectrochemical Water Splitting
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Advanced surface and interface engineering has been demonstrated to be of critical importance for the development of photoanodes for highly efficient photoelectrochemical (PEC) water oxidation. In this study, cobalt-sites-rich aza-fused conjugated microporous polymer was integrated on the nanoporous bismuth vanadate electrode. The hybrid BiVO4/eCMP-Co photoanode exhibited a high photocurrent density of 4.3 mA cm-2 at 1.23 VRHE and a very low onset potential of ~ 0.2 VRHE with an applied bias photon to current efficiency of 1.62% at around 0.6 VRHE. Moreover, studies on charge carrier kinetics showed that eCMP-Co can not only accelerate water oxidation kinetics but also significantly suppress surface recombination, thereby dramatically increasing charge transfer efficiency. These results demonstrate the great potential of conjugated polymers combined with metal coordination as heterogenous catalysts on photoelectrodes in PEC devices.
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| 2. |
- Ji, Yanan, et al.
(författare)
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Cascade photon upconversion amplification for selective multispectral narrow-band near-infrared photodetection
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Facing the fact that selective detection of multiple narrow spectral bands in the near-infrared (NIR) region still poses a fundamental challenge, we have, in this work, developed NIR photodetectors (PDs) using photon upconversion nanocrystals (UCNCs) combined with perovskite films. In order to conquer the relatively high pumping threshold of UCNCs, we designed a novel cascade amplification strategy for upconversion luminescence (UCL) through cascading the superlensing effect of dielectric microlens arrays and the plasmonic effect of gold nanorods, which readily leads to a UCL enhancement by more than four orders of magnitude under weak light irradiation. By accommodating multiple optical active lanthanide ions in a core-shell-shell hierarchical architecture, the developed PDs on top can detect three well-separated narrow bands in the NIR region, i.e., 808, 980, and 1540 nm, respectively. Due to the large UCL enhancement, the obtained PDs demonstrate extremely high responsivity of 30.73, 23.15, 12.20 A/W and detectivity of 5.36, 3.45, 1.91x10^11 Jones for the 808, 980, and 1540 nm light detection, respectively, together with short response times in the range of 80-120 ms. Moreover, we demonstrate for the first time that the response to the excitation modulation frequency of a PD can be employed to discriminate the incident light wavelength. We believe that our work provides a novel insight for developing NIR PDs, and that it can spur the development of other applications using upconversion nanotechnology.
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| 3. |
- Yang, Hao, et al.
(författare)
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Monolithic FAPbBr3 Photoanode for Photoelectrochemical Water Oxidation with Ultralow-Onset-Potential
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Despite considerable research efforts on photoelectrochemical (PEC) water splitting over the past few decades, its practical application is still impeded by the lack of efficient, stable, and scalable photoelectrodes. Herein, we demonstrate the facile fabrication of a metal-halide perovskite-based photoanode for PEC water oxidation. A hole transport material-free and precious metal-free FAPbBr3 photovoltaic (PV) device is fabricated for the first time to examine the charge separation performance of the FAPbBr3 absorber. With a planar structure using mesoporous carbon as a hole-conducting layer, the device achieved a solar-to-electrical power conversion efficiency of 9.2% and a Voc of 1.4 V. The solar cell architecture is successfully applied to build a monolithic photoanode with the FAPbBr3 absorber, carbon/graphite conductive protection layer, and NiFe catalyst layers for direct photo-driven water oxidation. With suitable energy band alignment and minimal contact loss, the photoanode delivers an ultralow onset potential below 0 V versus a reversible hydrogen electrode and a high applied bias photon-to-current efficiency of 8.5%. Stable operation exceeding 100 h under constant solar illumination is successfully reached by the application of UV filter protection. A detailed photothermal investigation confirms that the photothermal effect can improve the overall performance of the perovskite photoanode. The results in this report are of great significance in guiding the further development of PV material-based photoelectrodes for solar fuel applications.
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| 4. |
- Aprile, E., et al.
(författare)
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Effective Field Theory and Inelastic Dark Matter Results from XENON1T
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- In this work we expand on the XENON1T nuclear recoil searches and study the individual signals of Dark Matter interactions from operators up to dimension-eight in a Chiral Effective Field Theory (ChEFT) as well as a model of inelastic Dark Matter using data from the two science runs of the detector totalling 1 tonne*year exposure. For these analyses we extended the region of interest from [4.9, 40.9]keVnr to [4.9, 54.4]keVnr to enhance our sensitivity for signals that peak at nonzero energies. We show that the data is consistent with a background only hypothesis, with small excesses in the models which peak between 20 and 50keVnr, obtaining a maximum local discovery significance of 1.7 for the VVs ChEFT model for a WIMP mass of 70GeV/c2, and 1.8 for an iDM particle of 50GeV/c2 with a mass splitting of 100keV/c2. For each model we report 90% confidence level upper limits. We also report limits on three benchmark models of WIMP interaction using ChEFT for which we investigate the effect of isospin breaking interactions, reporting up to 6 orders of magnitude weaker limits with respect to the isospin conserving case driven by cancellations in the expected rate.
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| 5. |
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| 6. |
- Liu, Yawen, et al.
(författare)
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Solvent Engineering of Perovskite Crystallization for High Performance FAPbBr3 Perovskite Solar Cells Prepared in Ambient Condition
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- FAPbBr3 perovskite solar cells (PSCs) have attracted tremendous interest in recent years due to the high open circuit voltage and good stability. Commonly a step method is used to prepare the FAPbBr3 perovskite film. Here a mixed solvent approach for the second step is introduced. Formamidinium bromide (FABr) in 2-propanol (IPA)and Methanol (MeOH) mixture was applied in the second step, which resulted in favorable properties such as suitable solubility, high-quality crystallization, large grainsize, improved charge extraction properties and suppressed non-radiative recombination processes, and further enhance the power conversion efficiency (PCE) from 4.06% to 7.87%. As previously reported, methylammonium chloride (MACl) can help to improve the morphology and crystallinity of perovskite. To further prove the versatility of such a mixed solvent strategy and enhance the photovoltage performance,a small amount of MACl was added to the FABr solution with mixed solvents, and a high PCE of 9.23% was achieved under ambient conditions.
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| 7. |
- Liu, Yawen, et al.
(författare)
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The Effects of Dopant-Free Hole Transport Materials on n–i–p FAPbBr3 Perovskite Solar Cells under Ambient Processed
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Dopant-free organic hole transport materials (HTMs) remain highly desirable for stable and efficient ni-p perovskite solar cells but are rarely applied in formamidinium lead-bromide (FAPbBr3) underambient processing. Herein, we compare four dopant-free HTMs on FAPbBr3- perovskite solar cells (FAPbBr3-PSCs) according to their structure-property relationship. Among these, P3HT presents higher hole mobility, lower interface trap density, and lower nonradiative recombination, resulting in superior charge extraction and transport. The optimized device utilizing dopant-free P3HT shows a high open circuit voltage of 1.47 V and a champion power conversion efficiency (PCE) of 9.38% with greatly improved operational stability, making it among the highest performance in FAPbBr3-PSCs based ondopant-free HTMs. Also, to further improve the stability of P3HT- FAPbBr3 solar cells, the lower cost Carbon electrode was applied to replace the Au, and the resultant carbon-PSCs presented an impressive PCE of 8.9% with a high voltage of 1.44 V. It also keeps excellent stability that almost no degradation nearly one year.
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| 8. |
- Olson, Nathan D., et al.
(författare)
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precisionFDA Truth Challenge V2: Calling variants from short- and long-reads in difficult-to-map regions
- 2020
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The precisionFDA Truth Challenge V2 aimed to assess the state-of-the-art of variant calling in difficult-to-map regions and the Major Histocompatibility Complex (MHC). Starting with FASTQ files, 20 challenge participants applied their variant calling pipelines and submitted 64 variant callsets for one or more sequencing technologies (~35X Illumina, ~35X PacBio HiFi, and ~50X Oxford Nanopore Technologies). Submissions were evaluated following best practices for benchmarking small variants with the new GIAB benchmark sets and genome stratifications. Challenge submissions included a number of innovative methods for all three technologies, with graph-based and machine-learning methods scoring best for short-read and long-read datasets, respectively. New methods out-performed the 2016 Truth Challenge winners, and new machine-learning approaches combining multiple sequencing technologies performed particularly well. Recent developments in sequencing and variant calling have enabled benchmarking variants in challenging genomic regions, paving the way for the identification of previously unknown clinically relevant variants.
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| 9. |
- Pfeiffer, Thomas, et al.
(författare)
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Predicting the replicability of social and behavioural science claims in a crisis: The COVID-19 Preprint Replication Project
- 2023
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Replications are important for assessing the reliability of published findings. However, they are costly, and it is infeasible to replicate everything. Accurate, fast, lower-cost alternatives such as eliciting predictions could accelerate assessment for rapid policy implementation in a crisis. We elicited judgments from participants on 100 claims from preprints about an emerging area of research (COVID-19 pandemic) using an interactive structured elicitation protocol, and we conducted 29 new high-powered replications. After interacting with their peers, participant groups with lower task expertise (‘beginners’) updated their estimates and confidence in their judgements significantly more than groups with greater task expertise (‘experienced’). For experienced individuals, the average accuracy was 0.57 (95% CI: [0.53, 0.61]) after interaction, and they correctly classified 61% of claims; beginners’ average accuracy was 0.58 (95% CI: [0.54, 0.62]), correctly classifying 69% of claims. The difference in accuracy between groups was not statistically significant, and their judgments on the full set of claims were correlated (r=.48). These results suggest that both beginners and more experienced participants using a structured process have some ability to make better-than-chance predictions about the reliability of ‘fast science’ under conditions of high uncertainty. However, given the importance of such assessments for making evidence-based critical decisions in a crisis, more research is required to understand who the right experts in forecasting replicability are and how their judgements ought to be elicited.
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| 10. |
- Zhang, Chi, et al.
(författare)
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Crowd-funding Intention and Willingness-to-pay for a Sustainable Milk Product with Integrated Photovoltaic Water Pumping System in China
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- In comparison with current financing mechanisms for renewable energy systems, crowd-funding financing mechanism offers a new potential source of financing with recent use of social media. Crowd-funding financing mechanism can also increases the social supports for renewable energy systems as users and investors turn to be more actively engaged in energy systems. As a new potential source of financing, crowd-funding mechanism has different forms, including donation, lending, equity and product reward approaches. In this paper, discrete choice model was used to explore whether crowd-funding financing with a novel sociotechnical product reward practice, has the attractions for potential customers to pay for a more sustainable milk product with distributed photovoltaic (PV) system. We empirically investigated the product reward crowd funding with the specific integrated photovoltaic water pumping (PVWP) system in dairy milk production in China. 48 in-depth interviews were adopted for qualitative analysis of determinants of customer milk purchase decision. The ordered probit regression was employed with 357 online surveys to systematically estimate the purchase intention and willingness to pay value for the online-crowd-funding sustainable milk. Customer behaviours, environmental consciousness, and the individual socio-demographic factors were tested as potential explanatory variables. In the survey and depth interview samples, we found interviewees as potential customers showed strong purchase intentions to the crowd funding dairy milk for noticing milk quality and nutritious improvement, emission reduction and environmental benefits by the integrated PVWP system. In our findings of the regression results, the potential customers with higher income-level, at the age with young children or planning to have children were found with higher willingness to pay than other customers for crowd funding the sustainable dairy milk. The familiarity and popularity with online shopping and pre-sale purchase in China made customers more open and active towards pre-pay and crowd-funding mechanism.
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