| 1. |
- Chandrasekaran, Sundaram, et al.
(author)
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Advanced opportunities and insights on the influence of nitrogen incorporation on the physico-/electro-chemical properties of robust electrocatalysts for electrocatalytic energy conversion
- 2021
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In: Coordination chemistry reviews. - : Elsevier. - 0010-8545 .- 1873-3840. ; 449
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Research review (peer-reviewed)abstract
- The use of a wide range of methods for incorporating nitrogen atoms on robust catalysts has given rise to fundamental advances in the field of energy conversion and storage. Recently, nitrogen incorporation has proven to be able to fine-tune the electron densities of exposed active sites to create high-performance electrocatalysts. The preservation of a strong interface between the local atomic coordination of nitrogen atoms on bare carbon, single metal atoms, transition metal oxides, metal chalcogenides, and MXenes during synthesis plays an important role in producing an efficient electrocatalysts. In addition, the ability of nitrogen atoms to bind with carbon or metal atoms can be influenced by processing conditions. In this regard, this review is the first comprehensive overview of the range of synthetic strategies to form nitrogen incorporated catalysts and assess their chemical, structural, physical electronic property modification and their influence on electrocatalytic ORR, OER, and HER performance. This review will describe how specific strategies have been utilized to realise effective electrocatalytic systems, including the energy conversion of nitrogen incorporated catalysts, structural coordination, and material optimization. Finally, the main challenges to be considered in future investigations in order to initiate new research efforts in this promising research area are discussed.
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| 2. |
- Chen, Hualong, et al.
(author)
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Direct Observation of Photon Induced Giant Band Renormalization in 2D PdSe2 Dichalcogenide by Transient Absorption Spectroscopy
- 2023
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In: Small. - : John Wiley & Sons. - 1613-6810 .- 1613-6829. ; 19:46
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Journal article (peer-reviewed)abstract
- Insight into fundamental light-matter interaction as well as underlying photo-physical processes is crucial for the development of novel optoelectronic devices. Palladium diselenide (PdSe2), an important representative of emerging 2D noble metal dichalcogenides, has gain considerable attention owing to its unique optical, physical, and chemical properties. In this study, 2D PdSe2 nanosheets (NSs) are prepared using the liquid-phase exfoliation method. A broadband carrier relaxation dynamics from visible to near-infrared bands are revealed using a time-resolved transient absorption spectrometer, giving results that indicate band filling and bandgap renormalization (BGR) effects in the 2D PdSe2 NSs. The observed blue-shift of the transient absorption spectra at the primary stage and the subsequent red-shift can be ascribed to this BGR effect. These findings reveal the many-body character of the 2D TMDs material and may hold keys for applications in the field of optoelectronics and ultrafast photonics.
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| 3. |
- Gao, Lingfeng, et al.
(author)
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Emerging applications of MXenes for photodetection : Recent advances and future challenges
- 2022
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In: Materials Today. - : Elsevier. - 1369-7021 .- 1873-4103. ; 61, s. 169-190
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Journal article (peer-reviewed)abstract
- The development and applications of transition metal carbides, nitrides and carbonitrides, commonly denoted as MXenes, have during the last few years rapidly expanded in various technological fields owing to their unique and controllable properties. These materials exhibit competing performance comparing with traditional materials and have created numerous opportunities for technology markets. Taking the advantage of excellent optoelectronic features, MXenes have been utilized for the construction of photodetectors with various structures and unique functionalities. While the appli-cation of MXenes in this area can be traced back to 2016, we have during the recent three years witnessed a dramatic development of MXene-based photodetectors, calling for a timely review to guideline their future direction. In this work, synthetic strategies of pristine MXenes are briefly introduced and their properties are discussed focusing on the optoelectronic aspects that are fundamental for the photoelectric conversion. Recent advances of MXene-based photodetectors are comprehensively summarized based on different types of MXenes and innovative designs of device construction. Finally, we provide perspectives for future challenges and opportunities of MXene-based photodetectors, which may enlighten their further development.
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| 4. |
- Gao, Lingfeng, et al.
(author)
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Optical Properties of Few-Layer Ti3CN MXene : From Experimental Observations to Theoretical Calculations
- 2022
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In: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 16:2, s. 3059-3069
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Journal article (peer-reviewed)abstract
- Despite the emerging interest in research and development of Ti3CN MXene nanosheet (NS)-based optoelectronic devices, there is still a lack of in-depth studies of the underlying photophysical processes, like carrier relaxation dynamics and nonlinear photon absorption, operating in such devices, hindering their further and precise design. In this paper, we attempt to remedy the situation by fabricating few-layer Ti3CN NSs via combining selective etching and molecular intercalation and by investigating the carrier relaxation possesses and broadband nonlinear optical responses via transient absorption and Z-scan techniques. These results are complemented by first-principle theoretical analyses of the optical properties. Both saturable absorption and reverse saturable absorption phenomena are observed due to multiphoton absorption effects. The analysis of these results adds to the understanding of the basic photophysical processes, which is anticipated to be beneficial for the further design of MXene-based devices.
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