RESUMO
Recently, research on nonfullerene acceptors in organic solar cells has gradually become a hot topic due to such superior characteristics of light absorption and energy-level-convenient manipulation, multiformity of the photoactive material structures, as well as the extensive area in production compared to the fullerene derivatives. However, the nonfullerene acceptors evolved slowly before 2012 and, as a matter of fact, the power conversion efficiency values could only bear 2.0%. Strikingly, nonfullerene acceptors have developed at a fast pace since 2013, with the best device performance of 13.1% now. In this review, recent research progress on nonfullerene acceptors, including small molecules and polymers, are sorted and summarized on the basis of the different characteristics.
Assuntos
Fontes de Energia Elétrica , Fulerenos/química , Polímeros/química , Bibliotecas de Moléculas Pequenas/química , Energia Solar , Técnicas Eletroquímicas , Estrutura Molecular , Processos FotoquímicosRESUMO
The phthalimide (PhI) moiety has been attracting more attention as an excellent acceptor building block in donor-acceptor (D-A) conjugated polymers. In this paper; three D-A conjugated polymers with or without thiocarbonyl moieties are successfully prepared by the direct (hetero)-arylation polymerization (DHAP), which is an atom efficient and facile synthetic strategy to obtain polymer materials. Compared with the traditional carbon-carbon coupling reactions, this method possesses more advantages, including: fewer synthetic steps, avoidance of the preparation of the organometallic reagents, higher atom economy and fewer toxic byproducts, better compatibility with chemically sensitive functional groups and so on. All three of these designed PhI-based polymers exhibited favourable optoelectronic and thermal performance. The optical, thermodynamic and electrochemical properties of the synthesized polymers were systematically investigated using ultraviolet-visible (UV-vis) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and cyclic voltammetry (CV). The results of these three polymers indicated that thionation of the carbonyl was a highly effective methods to improve the properties of PhI-based polymers; and provided impetus for the development of thionated PhI derivatives for organic electronic applications.
Assuntos
Química Verde , Compostos Organometálicos/síntese química , Ftalimidas/química , Polímeros/síntese química , Eletrônica/instrumentação , Humanos , Teste de Materiais , Estrutura MolecularRESUMO
A new coherent laser communication detection scheme based on the channel-switching method is proposed. The detection front end of this scheme comprises a 90° optical hybrid and two balanced photodetectors which outputs the in-phase (I) channel and quadrature-phase (Q) channel signal current, respectively. With this method, the ultrahigh speed analog/digital transform of the signal of the I or Q channel is not required. The phase error between the signal and local lasers is obtained by simple analog circuit. Using the phase error signal, the signals of the I/Q channel are switched alternately. The principle of this detection scheme is presented. Moreover, the comparison of the sensitivity of this scheme with that of homodyne detection with an optical phase-locked loop is discussed. An experimental setup was constructed to verify the proposed detection scheme. The offline processing procedure and results are presented. This scheme could be realized through simple structure and has potential applications in cost-effective high-speed laser communication.
RESUMO
Porous N-doped carbon material (NCM) derived from deep eutectic solvent (DES) is successfully prepared. The preparation of NCM depends mainly on heating treatment and does not demand activation and filtration. The heating process contains three steps: (1) forming a DES that consists of glucose and urea at 100 °C; (2) preparing dried precursors by microwave; (3) and carbonizing the precursor. After heating, the resulting NCM can be obtained. The as-prepared NCM exhibits high specific surface area, rich micropores and strong Lewis basicity. Accordingly, NCMs show good adsorption performance for 4-nitrophenol or methylene blue in aqueous solution and thiophenic sulfurs in the oil phase. Apparently, NCM derived from DES not only possesses a simple preparation process, but also can remove a wide spectrum of organic pollutants. Therefore, the NCM prepared here may be promising for practical application.
RESUMO
The layered lithium-metal oxides are promising cathode materials for Li-ion batteries. Nevertheless, their widespread applications have been limited by the high cost, complex process, and poor stability resulting from the Ni2+/Li+ mixing. Hence, we have developed a facile one-spot method combining glucose and urea to form a deep eutectic solvent, which could lead to the homogeneous distribution and uniform mixing of transition-metal ions at the atomic level. LiNi0.5Co0.2Mn0.3O2 (NCM523) polyhedron with high homogeneity could be obtained through in situ chelating Ni2+, Co3+, and Mn4+ by the amid groups. The prepared material exhibits a relatively high initial electrochemical property, which is due to the unique single-crystal hierarchical porous nano/microstructure, the polyhedron with exposed active surfaces, and the negligible Ni2+/Li+ mixing level. This one-spot approach could be expanded to manufacture other hybrid transition-metal-based cathode materials for batteries.
RESUMO
C-X-C motif chemokine ligand 8 (CXCL8) is involved in tumor proliferation, migration, and invasion. However, the function of CXCL8 in colorectal cancer (CRC) is controversial. Here, we analyzed RNA-sequencing (RNA-seq) data to identify differentially expressed genes and pathways according to gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with CRC. The levels of the mRNA encoding CXCL8 were significantly increased in early and advanced stages of CRC, as well as in metastases and nonmetastasis cases using RNA-seq analysis (n = 91). These findings were consistent with immunohistochemical analysis of CXCL8 expression (n = 87). Protein-protein interaction (PPI) prediction combined with transcriptional profiling data revealed that CXCL8 levels positively correlated with cAMP responsive element binding protein 1 (CREB1)/ribosomal protein S6 kinase B1 (RPS6KB1) expression, which promotes cell proliferation and differentiation in high expression, while inversely correlated with the expression of Bcl2 associated agonist of cell death (BAD) protein to inhibit apoptosis during the progression of CRC. These findings provide compelling clinical and molecular evidence to support the conclusion that CXCL8 contributes to the genesis and progression of CRC.