| 1. |
- Chen, Haiyang, et al.
(author)
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A guest-assisted molecular-organization approach for >17% efficiency organic solar cells using environmentally friendly solvents
- 2021
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In: Nature Energy. - : NATURE PORTFOLIO. - 2058-7546. ; 6:11, s. 1045-1053
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Journal article (peer-reviewed)abstract
- The power conversion efficiencies (PCEs) of laboratory-sized organic solar cells (OSCs), usually processed from low-boiling-point and toxic solvents, have reached high values of over 18%. However, there is usually a notable drop of the PCEs when green solvents are used, limiting practical development of OSCs. Herein, we obtain certificated PCEs over 17% in OSCs processed from a green solvent paraxylene (PX) by a guest-assisted assembly strategy, where a third component (guest) is employed to manipulate the molecular interaction of the binary blend. In addition, the high-boiling-point green solvent PX also enables us to deposit a uniform large-area module (36 cm(2)) with a high efficiency of over 14%. The strong molecular interaction between the host and guest molecules also enhances the operational stability of the devices. Our guest-assisted assembly strategy provides a unique approach to develop large-area and high-efficiency OSCs processed from green solvents, paving the way for industrial development of OSCs. Organic solar cells processed from green solvents are easier to implement in manufacturing yet their efficiency is low. Chen et al. devise a guest molecule to improve the molecular packing, enabling devices with over 17% efficiency.
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| 2. |
- Chen, Xian-Kai, et al.
(author)
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A unified description of non-radiative voltage losses in organic solar cells
- 2021
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In: Nature Energy. - : Springer Nature. - 2058-7546. ; 6:8, s. 799-806
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Journal article (peer-reviewed)abstract
- Organic solar cells based on non-fullerene acceptors have enabled high efficiencies yet their charge dynamics and its impact on the photovoltaic parameters are not fully understood. Now, Chen et al. provide a general description of non-radiative voltage losses in both fullerene and non-fullerene solar cells. Recent advances in organic solar cells based on non-fullerene acceptors (NFAs) come with reduced non-radiative voltage losses (Delta V-nr). Here we show that, in contrast to the energy-gap-law dependence observed in conventional donor:fullerene blends, the Delta V-nr values in state-of-the-art donor:NFA organic solar cells show no correlation with the energies of charge-transfer electronic states at donor:acceptor interfaces. By combining temperature-dependent electroluminescence experiments and dynamic vibronic simulations, we provide a unified description of Delta V-nr for both fullerene- and NFA-based devices. We highlight the critical role that the thermal population of local exciton states plays in low-Delta V-nr systems. An important finding is that the photoluminescence yield of the pristine materials defines the lower limit of Delta V-nr. We also demonstrate that the reduction in Delta V-nr (for example, <0.2 V) can be obtained without sacrificing charge generation efficiency. Our work suggests designing donor and acceptor materials with high luminescence efficiency and complementary optical absorption bands extending into the near-infrared region.
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| 3. |
- Cherp, Aleh, et al.
(author)
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National growth dynamics of wind and solar power compared to the growth required for global climate targets
- 2021
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In: Nature Energy. - : Springer Science and Business Media LLC. - 2058-7546. ; 6:7, s. 742-754
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Journal article (peer-reviewed)abstract
- Climate mitigation scenarios envision considerable growth of wind and solar power, but scholars disagree on how this growth compares with historical trends. Here we fit growth models to wind and solar trajectories to identify countries in which growth has already stabilized after the initial acceleration. National growth has followed S-curves to reach maximum annual rates of 0.8% (interquartile range of 0.6–1.1%) of the total electricity supply for onshore wind and 0.6% (0.4–0.9%) for solar. In comparison, one-half of 1.5 °C-compatible scenarios envision global growth of wind power above 1.3% and of solar power above 1.4%, while one-quarter of these scenarios envision global growth of solar above 3.3% per year. Replicating or exceeding the fastest national growth globally may be challenging because, so far, countries that introduced wind and solar power later have not achieved higher maximum growth rates, despite their generally speedier progression through the technology adoption cycle.
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| 4. |
- Crispin, Xavier
(author)
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Carbon nanotubes get high
- 2016
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In: NATURE ENERGY. - : NATURE PUBLISHING GROUP. - 2058-7546. ; 1
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Journal article (other academic/artistic)abstract
- Waste heat can be converted to electricity by thermoelectric generators, but their development is hindered by the lack of cheap materials with good thermoelectric properties. Now, carbon-nanotube-based materials are shown to have improved properties when purified to contain only semiconducting species and then doped.
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| 5. |
- Cui, Yong, et al.
(author)
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Wide-gap non-fullerene acceptor enabling high-performance organic photovoltaic cells for indoor applications
- 2019
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In: NATURE ENERGY. - : NATURE PUBLISHING GROUP. - 2058-7546. ; 4:9, s. 768-775
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Journal article (peer-reviewed)abstract
- Organic photovoltaic cells are potential candidates to drive low power consumption off-grid electronics for indoor applications. However, their power conversion efficiency is still limited by relatively large losses in the open-circuit voltage and a non-optimal absorption spectrum for indoor illumination. Here, we carefully designed a non-fullerene acceptor named IO-4CI and blend it with a polymer donor named PBDB-TF to obtain a photoactive layer whose absorption spectrum matches that of indoor light sources. The photovoltaic characterizations reveal a low energy loss below 0.60 eV. As a result, the organic photovoltaic cell (1 cm(2)) shows a power conversion efficiency of 26.1% with an open-circuit voltage of 1.10 V under a light-emitting diode illumination of 1,000 lux (2,700 K). We also fabricated a large-area cell (4 cm(2)) through the blade-coating method. Our cell shows an excellent stability, maintaining its initial photovoltaic performance under continuous illumination of the indoor light source for 1,000 hours.
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| 6. |
- Dekker, Mark M., et al.
(author)
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Identifying energy model fingerprints in mitigation scenarios
- 2023
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In: Nature Energy. - : Springer Nature. - 2058-7546. ; 8:12, s. 1395-1404
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Journal article (peer-reviewed)abstract
- Energy models are used to study emissions mitigation pathways, such as those compatible with the Paris Agreement goals. These models vary in structure, objectives, parameterization and level of detail, yielding differences in the computed energy and climate policy scenarios. To study model differences, diagnostic indicators are common practice in many academic fields, for example, in the physical climate sciences. However, they have not yet been applied systematically in mitigation literature, beyond addressing individual model dimensions. Here we address this gap by quantifying energy model typology along five dimensions: responsiveness, mitigation strategies, energy supply, energy demand and mitigation costs and effort, each expressed through several diagnostic indicators. The framework is applied to a diagnostic experiment with eight energy models in which we explore ten scenarios focusing on Europe. Comparing indicators to the ensemble yields comprehensive ‘energy model fingerprints’, which describe systematic model behaviour and contextualize model differences for future multi-model comparison studies.
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| 7. |
- Diaz-Morales, Oscar
(author)
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Impurity as a virtue
- 2020
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In: NATURE ENERGY. - : NATURE PUBLISHING GROUP. - 2058-7546. ; 5:3, s. 193-194
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Journal article (other academic/artistic)abstract
- Understanding the activity and stability of oxygen-evolving anodes is crucial for developing better water splitting electrolysers. Researchers now show the importance of interactions between iron and hydr(oxy)oxide hosts in dynamically-stable electrocatalysts that balance dissolution and deposition of iron present in the electrolyte.
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| 8. |
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| 9. |
- Edoff, Marika, 1965-
(author)
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Using both sides of the panel
- 2023
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In: Nature Energy. - : Springer Nature. - 2058-7546. ; 8:1, s. 15-16
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Journal article (other academic/artistic)abstract
- Bifaciality allows the harvest of sunlight from both sides of a solar cell and thereby increases power output, but the efficiency of thin-film devices lags behind that of silicon counterparts. Now, researchers demonstrate a bifacial Cu(In,Ga)Se2-perovskite tandem solar cell with a 28 mW/cm2 power output under front and rear illumination.
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| 10. |
- Edvinsson, Tomas, Professor, 1970-
(author)
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A concentrated effort
- 2019
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In: NATURE ENERGY. - : Springer Science and Business Media LLC. - 2058-7546. ; 4:5, s. 354-355
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Journal article (other academic/artistic)abstract
- While recent gains in the efficiency of photoelectrochemical devices for hydrogen production are encouraging, high efficiency is rarely combined with high power output, which is important for large-scale viability. Towards this goal, researchers now demonstrate a promising thermally integrated device driven by concentrated solar irradiation.
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