High-current density (≥1 A cm–2) is a critical factor for large-scale industrial application of water-splitting electrocatalysts, especially seawater-splitting. However, it still remains a great challenge to reach high-current density due to the lack of active and stable intrinsic catalytic active sites in catalysts. Herein, we report an original three-dimensional self-supporting graphdiyne/molybdenum oxide (GDY/MoO3) material for efficient hydrogen evolution reaction via a rational design of “sp C–O–Mo hybridization” on the interface. The “sp C–O–Mo hybridization” creates new intrinsic catalytic active sites (nonoxygen vacancy sites) and increases the amount of active sites (eight times higher than pure MoO3). The “sp C–O–Mo hybridization” facilitates charge transfer and boosts the dissociation process of H2O molecules, leading to outstanding HER activity with high-current density (>1.2 A cm–2) in alkaline electrolyte and a decent activity and stability in natural seawater. Our results show that high-current density electrocatalysts can be achieved by interfacial chemical bond engineering, three-dimensional structure design, and hydrophilicity optimization.

Conjugated polyacetylenes having pendant fullerene and/or porphyrin groups were prepared by copolymerization in the presence of [Rh(nbd)Cl]2−NEt3 in CHCl3. The photochemical and electrochemical properties of the polymers were studied by UV−vis spectroscopy and voltammetry. The photoinduced charge-transfer properties of the monolayer films were also measured by a three-electrode cell technique. More importantly, poly(1a 0.2-co-5 0.8) shows a high capacity to form a photoinduced charge-separated state and to produce steady and prompt photocurrent at the irradiation of 21.2 mW cm-2 white light. We estimate an aerobic IPCE value of 0.15% for a true monolayer coverage of poly(1a 0.2-co-5 0.8) at its peak absorption around 440 nm (the maximum of the Soret band).

The ladder-type nonacyclic arene (bis(thieno[3,2b]thieno)cyclopentafluorene (BTTF)) has been designed and synthesized through fusing thienothiophenes with the fluorene core from the synthon of dimethyl9 ,9-dioctyl-2,7-bis(thieno[3,2-b]thiophen-2-yl)fluorene-3,6-dicarboxylate. With BTTF as the central donor unit, an ovel acceptor-donor-acceptor (A-D-A) type non-fullerene small-molecule acceptor (BTTFIC)w as prepared with 1,1-dicyanomethylene-3-indanones (IC) as the peripheral acceptor units.T he energy level of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of BTTFIC locate at À5.56 and À3.95 eV,r espectively,p resentingalow opticalb and gap of 1.58 eV.E ncouragingly,p olymer solar cells based on the blends of BTTFIC with both the representative wide-andl ow-bandgap polymer donors (PBDB-T, 1.82 eV.P TB7-Th, 1.58 eV) offer powerc onversion efficiencies over 8% (8.78 AE 0.18 %f or PBDB-T:BTTFIC and 8.18 AE 0.29 % for PTB7-Th:BTTFIC). These results highlightt he advantage of ladder-type BTTF on the preparation of nonfullerene acceptors with extended conjugated backbones.[a] X.Scheme2.Synthesis of ladder-typenonacyclic arene of bis(thieno[3,2-b]thieno)cyclopentafluorene (BTTF)and non-fullerene acceptorofBTTFIC.

A new self-assembly system between a PPV derivative and an organofullerene through a three-point hydrogen-bonding interaction was prepared. The formation of hydrogen bonding was confirmed by 1H NMR studies in CDCl3. Fluorescence quenching experiments indicated that the fluorescence of U-PPV was greatly quenched by DAP-C60 (K SV = 5.8 × 104 M-1).

The design of a sandwich structure is conducive to enhancing the dielectric constant and energy density of SrTiO3 nanocomposite thick films.

The doping process and thermoelectric properties of donor-acceptor (D-A) type copolymers are investigated with the representative poly([2,6′-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b] dithiophene]3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophenediyl)) (PTB7-Th). The PTB7-Th is doped by FeCl3 and only polarons are induced in its doped films. The results reveal that the electron-rich donor units within PTB7-Th lose electrons preferentially at the initial stage of the oxidation and then the acceptor units begin to be oxidized at a high doping concentration. The energy levels of polarons and the Fermi level of the doped PTB7-Th remain almost unchange with different doping levels. However, the morphology of the PTB7-Th films could be deteriorated as the doping levels are improved, which is one of the main reasons for the decrease of electrical conductivity at the later stage of doping. The best electrical conductivity and power factor areobtained to be 42.3 S⋅cm−1 and 33.9 μW⋅mK−2, respectively, in the doped PTB7-Th film at room temperature. The power factor is further improved to 38.3 μW⋅mK−2 at 75 °C. This work may provide meaningful experience for development of D-A type thermoelectric copolymers and may further improve the doping efficiency.

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A satisfactory material with high adsorption capacity is urgently needed to solve the serious problem of environment and human health caused by lead pollution. Herein, hydrogen-substituted graphdiyne (HsGDY) was successfully fabricated and employed to remove lead ions from sewage and lead-containing blood. The as-prepared HsGDY exhibits the highest adsorption capacity of lead among the reported materials with a maximum adsorption capacity of 2,390 mg/g, i.e., ~five times larger than that of graphdiyne (GDY). The distinguished hexagonal hole and stack mode of HsGDY allows the adsorption of more lead via its inner side adsorption mode in one single unit space. In addition, the Pb 6s and H 1s hybridization promotes the strong bonding of lead atom adsorbed at the acetylenic bond of HsGDY, contributing to the high adsorption capacity. HsGDY can be easily regenerated by acid treatment and showed excellent regeneration ability and reliability after six adsorption-regeneration cycles. Langmuir isotherm model, pseudo second order, and density functional theory (DFT) demonstrated that the lead adsorption process in HsGDY is monolayer chemisorption. Furthermore, the HsGDY-based portable filter can handle 1,000 μg/L lead-containing aqueous solution up to 1,000 mL, which is nearly 6.67 times that of commercial activated carbon particles. And, the HsGDY shows good biocompatibility and excellent removal efficiency to 100 μg/L blood lead, which is 1.7 times higher than that of GDY. These findings suggest that HsGDY could be a promising adsorbent for practical lead and other heavy metal removal.