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Photocatalysis water treatment without artificial energy is cost‐effective, waste‐free and sustainable. Coventional powder photocatalysts have tiny contact surfaces, low catalytic efficiency, and are difficult to recycle and reuse, restricting their usage. Herein, a Lignin@t‐FeC2O4/g‐C3N4 material is developed by engineering hollow quadrangle t‐FeC2O4 and g‐C3N4 nanosheets on lignin membranes through facile impregnation coating and precipitation reaction. Fast mass transport, catalytic activity and accessibility characterize hollow tetragonal FeC2O4·2H2O. TEM, SEM and FTIR show that lignin binds t‐FeC2O4 and g‐C3N4. The g‐C3N4 nanosheets are uniformly wrapped on the surface of lignin fibers, and t‐FeC2O4 is loaded between them. This structure increases visible light absorption and active site‐contaminant contact. The chain reaction produces extremely active hydroxyl radicals from hydrogen peroxide because the Lignin@t‐FeC2O4/g‐C3N4 modules are rich inFeII, according to XPS. Transient photocurrent response curves and electrochemical impedance spectroscopy suggest a promoted charge migration and isolation at the redox reaction interface in the Lignin@t‐FeC2O4/g‐C3N4 system. As a result, Lignin@t‐FeC2O4/g‐C3N4 degrades 99% Rhodamine B within 40 minutes, and this performance is stable even under difficult conditions, such as low hydrogen peroxide concentration and high pH. This study combines lignin membranes with the photo‐Fenton reaction, and thus provides new concept for the development and application of membranes and photocatalysis. [ABSTRACT FROM AUTHOR]

The hydrogen production by water electrolysis has attracted great research interest as a sustainable approach for clean energy production. However, such process is plagued by the use of high‐cost precious metal‐based catalysts (such as Pt, RuO2). Hereby, the use of a low‐cost Nitrogen and Sulfur co‐doped carbon‐supported cobalt sulfide dual‐functional electrocatalyst derived from imidazole modified lignin for overall water splitting is presented. To introduce nitrogen and sulfur heteroatoms in the carbon structure, lignin is modified by imidazolation through thiol‐alkynes click reaction. Imidazole‐lignin shows a strong chelation tendancy with cobalt salt, and N and the S co‐doped cobalt sulfide catalyst (IL‐Co@GC‐PO) is obtained by pyrolysis. The IL‐Co@GC‐PO has an oxygen evolution potential of 1.57 V and a hydrogen evolution overpotential of 204 mV at a current density of 10 mA cm−2. During the overall water splitting process, the IL‐Co@GC‐PO catalysts require only 1.58 V to reach a current density of 10 mA cm−2, which is equivalent to the performance of the system composed of the noble metal Pt/C||RuO2. This work not only provides a strategy for the preparation of N and S co‐doped cobalt sulfide catalysts, but also provides guidance for using lignin as a carbon source to design and develop cheap electrocatalysts. [ABSTRACT FROM AUTHOR]

In this paper, lignin-based nanofiber materials with excellent adsorption performance were prepared by electrospinning technology with waste lignin as raw material and doped Ni-MOF-74. Through a series of characterization of the adsorbent, the effects of fiber morphology, pore size distribution, and doping Ni-MOF-74 on chlorobenzene adsorption performance were studied. It showed that doping Ni-MOF-74 could effectively increase the specific surface area of the adsorbent, enrich the pore structure, which was conductive to the adsorption. The results showed that Ni-MOF-74 doped lignin fiber exhibits excellent chlorobenzene adsorption performance compared with Ni-MOF-74 material and lignin fiber, and the maximum adsorption capacity can reach 58.49 g/g. According to the calculation of Langmuir equation, the chemical adsorption plays a leading role in the adsorption process of chlorobenzene. [ABSTRACT FROM AUTHOR]

Ionic conductive hydrogels prepared from various biological macromolecules are ideal materials for the manufacture of human motion sensors from the perspective of resource regeneration and environmental sustainability. However, it is still challenging to prepare hydrogels with both high toughness and self-healing ability. In this study, lignin-based β-CD-PVA (LCP) self-healing conductive hydrogels with high tensile properties were prepared by one-step method using alkali lignin as a plasticizer. Compared with PVA hydrogel, the maximum storage modulus and elongation were increased by 2.5 and 20.0 times, respectively. Uniform distribution of lignin can increase the fluidity and distance of polymer molecular chains, thus improving the viscoelastic and tensile properties of the LCP self-healing hydrogel. LCP hydrogels can maintain self-healing ability in both high (45 °C) and low temperature (0 °C) environments, and the self-healing ability is not affected by pH. Moreover, it also has good conductivity, anti-bacterial, thermostability, and anti-UV property, which has a good application prospect in the field of 3D printing and wearable electronic devices, which expands the efficient utilization of lignin in biorefinery. [ABSTRACT FROM AUTHOR]

The aminated lignin anchored bimetallic catalyst based on molecular surface modification showed excellent electrocatalytic performance, and the half wave potential of ORR reached 0.81v, which was equivalent to Pt/C. [Display omitted] • Nitrogen was introduced in situ on the surface of lignin by molecular level modification technology, which increased the active sites of oxygen reduction and improved the electrochemical properties of lignin. • The amine groups on the surface of amine lignin have strong ability to complex metals, effectively control the metal dispersion and particle size, which is conducive to the enhancement of conductivity and current density. • Transition metals Ni and Co exist in carbon matrix as the form of composite nanoparticles, which can effectively reduce the potential, improve the catalytic performance of oxygen reduction and oxygen precipitation. The M-C-N type catalyst prepared by doping with non-metal elements and transition metal elements is considered as a substitute for traditional precious metals to play a more significant role in the electrochemical field. However, the uncontrolled reunion of metal particles has become the main factor limiting the improvement of its performance. Therefore, this work proposes using lignin as a carbon source, and amine groups with strong coordination ability are introduced into the structure through the surface modification strategy so that the metal is embedded in the carbon-based framework in a chelated form to control the particle size. Compared with the metal catalyst prepared by unmodified lignin, the metal catalyst prepared by amination modification exhibits a smaller particle size and more uniform dispersion. Electrochemical performance results show that the bimetallic catalyst AL-Ni/Co@GC supported by amine-based lignin exhibits catalytic activity comparing with commercial electrocatalysts Pt/C and RuO 2 in ORR and OER, and also has higher stability and methanol resistance. This work not only provides a strategy for the controllable structure of carbon-based metal catalysts, but also has specific guiding significance for the design and development of cheap electrocatalysts and the utilization of new energy sources. [ABSTRACT FROM AUTHOR]