Dongjun Lv

The GO-regulated open SnO ₂ /N-doped carbon/rGO framework improves structural stability and sustains 926.4 mAh g ⁻¹ after 200 cycles at 0.1 A g ⁻¹ .

The intrinsically low electronic conductivity and sluggish ion-transport kinetics inherent to organic electrode materials present severe obstacles toward their practical application in high-performance lithium-ion batteries. Herein, we present a molecular conjugation engineering strategy to construct two cobalt phthalocyanine-based covalent organic frameworks through Schiff-base condensation between tetraaminophthalocyanine cobalt and two aldehyde linkers with distinct conjugation lengths—p-phthalaldehyde and 4,4'-biphenyldicarboxaldehyde. The resulting cobalt phthalocyanine tetraamine-4,4'-biphenyl dialdehyde (CoTAPc-BPDA) features an extended π-conjugated skeleton and a porous architecture, whereas cobalt phthalocyanine tetraamine-p-phthalaldehyde (CoTAPc-PDA) serves as a structurally analogous counterpart with shorter conjugation length. Benefiting from the extended conjugation, CoTAPc-BPDA achieves a significantly enhanced electronic conductivity of 5.77 × 10−5 S cm−1, while the well-defined porous structure facilitates efficient electrolyte penetration and rapid ion diffusion. When evaluated as anodes for lithium-ion batteries, CoTAPc-BPDA delivers a high reversible capacity of 863.61 mAh g−1 after 200 cycles at 100 mA g−1. Complementary DFT calculations reveal that conjugation extension narrows the bandgap, optimizes charge redistribution around Co centers, and reduces the Li ions migration energy barrier. This molecular conjugation engineering strategy establishes a synergistic pore-electron-ion coupling mechanism, providing fundamental insights for the rational design of high-performance organic anodes with favorable electrode/electrolyte interfacial properties.

An organic-free, high alkalinity strategy for Y zeolite synthesis was developed to provide an efficient and environmentally friendly route for zeolite production. The effects of synthesis parameters and seed crystals on crystallization were systematically investigated, and kaolin was used as an alternative silica alumina source.After ultra stabilization, USY/ASA composites were prepared by the sol-gel method. The physicochemical properties are characterized by means of XRD, SEM,BET,FT-IR and NH₃-TPD, as well as hydrocracking activity of USY/ASA. Under optimal conditions (90 °C, 28 h, 10% directing agent, and molar ratio of 3Na2O：Al2O3：8.5-9.5SiO2：75H2O), the obtained Y zeolite exhibited a relative crystallinity of 182.35%, a framework SiO2/Al2O3 ratio of 4.8, and a yield of 50.73 wt.%. A The NiW/USY/ASA catalyst showed excellent hydrocracking performance for n-decane, achieving 76.41% C10 conversion and 56.07% medium-oil yield at the reaction conditions of 340 ℃, 4.0 MPa, 500 Nm3/m3 hydrogen-to-oil ratio and WHSV 4 h-1 .This work establishes an environmental friendly, template-free strategy for Y zeolite synthesis and demonstrates its strong potential for high-performance hydrocracking catalysts due to its tailored acidity and graded pore architecture.

Lithium-ion batteries (LIBs) can benefit from transition metal oxides as anode materials because of their high theoretical capacities. However, volume expansion during cycling restricts their application. In this study, cobalt phthalocyanine modified by tert-butyl groups (tBuCoNc), with "steric-electronic" dual regulation, is used. The tert-butyl groups serve as a bridge for molecular design and property optimization. The cobalt oxide/nitrogen-doped graphene composites are constructed. The conjugated planar structure enhances charge transport, while tert-butyl substituents provide steric hindrance that improves structural stability and prevents nanoparticle aggregation. Upon pyrolysis, cobalt centers are transformed into uniformly dispersed cobalt oxide nanocrystals within a nitrogen-doped carbon matrix, offering abundant active sites that facilitate ion diffusion and electrolyte contact. The final composite, formed via π-π stacking and thermal treatment, exhibits strong synergistic effects between cobalt oxide and N-doped graphene. Electrochemical testing reveals an impressive initial discharge capacity of 1556.5 mAh g^-1 at 100 mA g^-1 and 741.1 mAh g^-1 after 100 cycles, highlighting its potential as a high-performance anode material for next-generation LIBs.

Photodetectors have important applications in science and commerce, but achieving high-performance broad-spectrum detection is still challenging. In this work, a photosensitive composite (Y-TiOPc@SQ1) consisting of Y-type titanyl phthalocyanine (Y-TiOPc) and squaraine (SQ1) was constructed using a bulk heterojunction strategy. Research shows that the photodetector based on Y-TiOPc@0.5%SQ1 (Y-TiOPc@0.5%SQ1-PD) exhibits excellent photodetection properties from 365 nm to 940 nm. At a low intensity of 0.01 mW cm⁻², the external quantum efficiency (EQE) at 365 nm is as high as 12 131%, and the photoresponsivity (R) is 35 683 mA W⁻¹. Compared to Y-TiOPc-PD, it exhibits significant enhancements in the NIR region, with R and EQE increasing by 1.62-fold (700 nm), 1.75-fold (765 nm), 1.69-fold (850 nm), and 2.25-fold (940 nm). In addition, the device exhibits prompt, steady and reproducible photocurrent response curves. Such high performances are attributed to the co-sensitization synergistic coupling enhancement effect between Y-TiOPc NPs and SQ1, the improvement in carrier generation efficiency, separation efficiency and transport rates due to bulk heterojunctions, and the enhancement of external hole tunneling injection efficiency assisted by interfacial trapped electrons. This study demonstrates that the bulk heterojunction strategy based on phthalocyanine and squaraine can effectively improve the performance of photodetectors, offering a novel approach for developing high-sensitivity, wide-spectrum photodetectors.