Two novel two-dimensional quinoxaline derivatives, DTPQx and DTDBPz, based copolymers, P2 and P3, were synthesized through Suzuki polycondensation reaction. Meanwhile, DPQx based polymer P1 was also designed for comparison. The UV-vis absorptions, thermal stability, energy levels, field-effect carrier mobilities and photovoltaic characteristics of the se three copolymers were systematically evaluated to understand the relationship between the polymer structure at the molecular level and the photovoltaic performances. Photovoltaic cells based on the two-dimensional quinoxaline-based polymers, P2 and P3, with a structure of ITO/PEDOT:PSS /Polymer:PC71BM /Ca/Al exhibited PCEs of over 3% compared to the PCE of less than 2% in the P1-based device.
An ideal porous adsorbent toward uranium with not only large adsorption capacity and high selectivity but also broad applicability even under rigorous conditions is highly desirable but still extremely scarce. In this work, a porous adsorbent, namely [NH
4
]
+
[COF‐SO
3
−
], prepared by ammoniating a SO
3
H‐decorated covalent organic framework (COF) enables remarkable performance for uranium extraction. Relative to the pristine SO
3
H‐decorated COF (COF‐SO
3
H) with uranium adsorption capacity of 360 mg g
−1
, the ammoniated counterpart of [NH
4
]
+
[COF‐SO
3
−
] affords ultrahigh uranium uptake up to 851 mg g
−1
, creating a 2.4‐fold enhancement. Such a value is the highest among all reported porous adsorbents for uranium. Most importantly, a large distribution coefficient,
K
d
U
, up to 9.8 × 10
6
mL g
−1
is observed, implying extremely strong affinity toward uranium. Consequently, [NH
4
]
+
[COF‐SO
3
−
] affords highly selective adsorption of uranium over a broad range of metal ions such as S
U/Cs
= 821, S
U/Na
= 277, and S
U/Sr
= 124, making it as effective uranium adsorbent from seawater, resulting in amazing uranium adsorption capacity of 17.8 mg g
−1
. Moreover, its excellent chemostability also make it an effective uranium adsorbent even under rigorous conditions (pH = 1, 8, and 3
m
acidity).
An efficient metal-free catalytic system has been developed based on hexagonal boron carbon nitride (h-BCN) nanosheets for the dehydrogenation of N-heterocycles with visible light; hydrogen gas is released in the process, and thus no proton acceptor is needed. This acceptorless dehydrogenation of hydroquinolines, hydroisoquinolines, and indolines to the corresponding aromatic N-heterocycles occurred in excellent yield under visible-light irradiation at ambient temperature. With h-BCN as the photocatalyst and water as the solvent, this environmentally benign protocol shows broad substitution tolerance and high efficiency.
PbS quantum dots (PbS QDs) were attached to TiO2 nanotubes on both the inside and outside surfaces of the nanotubes by using thiolactic acid, a bifunctional linker. The PbS QDs with diameters of 4−5 nm were controlled by adjusting the concentration of thiolactic acid. The PbS QDs can be placed only inside the nanotubes by first blocking the outer surface of the TNTs with the double-chain cationic surfactant. The photocatalytic activity and stability of PbS/TiO2 nanotubes were evaluated for the photodegradation of organic dyes. The results indicate that the functionalized TiO2 nanotubes were superior catalysts for photodegradation of cationic dyes. Additionally, the quantum dots enhance the activity and expand the usable portion of the solar spectrum.
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