Lignin colloidal spheres (LCSs) are promising biomaterials for application in drug storage and delivery, pollutant adsorption, and ultraviolet protection due to their biocompatibility, amphiphilicity, and conjugated structure. However, wide size distribution of LCSs greatly limits their performances, especially in many precise and advanced applications. Herein, the fabrication of monodispersed LCSs with tailorable sizes ranging from the nanoscale to microscale is reported. Lignin raw materials are first fractionated by solvent extraction, and then the lignin fraction is used to fabricate monodispersed LCSs by solvent/antisolvent self‐assembly. The underlying mechanism for the formation of monodispersed LCS is primarily ascribed to the improved homogeneity of long‐range intermolecular forces, especially the electrostatic forces and hydrophobic forces, between lignin molecules. Moreover, by manipulating the short‐range order of LCSs, an innovative application of lignin as bio‐photonic materials with tunable structural colorations (e.g., red, green, or blue) is demonstrated. This work not only provides deep insight and an effective strategy to eliminate the serious inhomogeneity of LCSs, but also makes lignin resources have great potential as biodegradable and biocompatible photonic materials in diverse advanced optical application fields such as photonic devices, anti‐counterfeiting labels, and structural color pigments.

BACKGROUND: Distillation is a separation process with a high energy consumption. Therefore, energy-saving optimizations of the distillation process have become particularly significant. However, developing methods to quickly choose the best energysaving distillation sequence for the separation of multiple components has become a key problem. RESULTS: In this paper, the Distillation Sequence Morphometry Analysis Method (DSMAM) was established to quickly screen energy-saving and efficient distillation sequences and was integrated with a Dividing-wall column (DWC) device, which has more industrial significance. Meanwhile, an evaluation and screening index η of separated multicomponent energy-saving distillation sequences was proposed. Finally, based on the DSMAM, and combined with Microsoft Visual Basic 6.0 (VB) and Aspen Plus V11 (Aspen) software, a set of distillation sequence screening and evaluation programs of four-component separation systems was generated. The distillation column sequence with high thermodynamic efficiency and the energy-saving coupling structure of distillation were obtained quickly and accurately. CONCLUSION: This program was applied to the separation of the n-butane-benzene-n-heptane-n-nonane system. It was able to quickly obtain the first three energy-saving distillation sequences without thermal coupling and the first three energy-saving distillation sequences in the search space. The direct-thermal coupling distillation sequence of the energy-saving fluid was integrated and coupled, providing a preliminary design reference for industrial design and application.

Alkali lignin (AL) has attracted great attention as a material for treating dye wastewater due to its low cost and environmental friendliness. However, the unique structure and aggregation characteristics of AL regarding the dye wastewater removal mechanism have not been systematically revealed. Here, the removal process of typical cationic dye contaminants (methylene blue, MB) from dye wastewater by AL at different pH was explored and the unique synergistic effect mechanism of adsorption and flocculation was revealed. With increasing pH, the removal rate initially increased and then decrease. With increasing MB concentration, the optimal pH value corresponding to the maximum adsorption rate increased regularly. Zeta potential and Fourier transform infrared spectroscopy (FTIR) showed that electrostatic and π–π interactions and hydrogen bonding consisted push-pull balance under the influence of pH. In addition, scanning electron microscopy (SEM), ultraviolet and visible spectrum (UV) and particle size analysis showed that the aggregate structure and synergistic mechanism changed with the solution pH and concentration. In the low concentration solution, adsorption dominated. While in the high concentration solution, flocculation dominated. The removal mechanism consisted of the synergy of adsorption and flocculation laying the foundation for the efficient and environmentally friendly treatment of dye wastewater by AL.

Microelectronic devices are developing rapidly in portability, wearability, and implantability. This puts forward an urgent requirement for the delicate deposition process of materials. Electrohydrodynamic printing has attracted academic and industrial attention in preparing ultrahigh-density microelectronic devices as a new noncontact, direct graphic, and low-loss thin film deposition process. In this work, a printed graphene with narrow line width is realized by combining the electrohydrodynamic printing and surface treatment. The line width of printed graphene on the hydrophobic treatment surface reduced from 80 to 28 μm. The resistivity decreased from 0.949 to 0.263 Ω·mm. Unexpectedly, hydrophobic treatment can effectively induce random stacking of electrohydrodynamic printed graphene, which avoids parallel stacking and agglomeration of graphene sheets. The performance of printed graphene is thus effectively improved. After optimization, a graphene planar supercapacitor with a printed line width of 28 μm is successfully obtained. Its capacitance can reach 5.39 mF/cm2 at 50 mV/s, which is twice higher than that of the untreated devices. The device maintains 84.7% capacitance after 5000 cycles. This work provides a reference for preparing microelectronic devices by ultrahigh precision printing and a new direction for optimizing two-dimensional material properties through stacking adjustment.

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