This review details recent progress in the conversion of technical lignins to multi-functional, high-value, and promising carbon fiber materials, and discusses their applications.

A facile pathway of the electrocatalytic nitrogen oxidation reaction (NOR) to nitrate is proposed, and Ru‐doped TiO2/RuO2 (abbreviated as Ru/TiO2) as a proof‐of‐concept catalyst is employed accordingly. Density functional theory (DFT) calculations suggest that Ruδ+ can function as the main active center for the NOR process. Remarkably doping Ru into the TiO2 lattice can induce an upshift of the d‐band center of the Ru site, resulting in enhanced activity for accelerating electrochemical conversion of inert N2 to active NO*. Overdoping of Ru ions will lead to the formation of additional RuO2 on the TiO2 surface, which provides oxygen evolution reaction (OER) active sites for promoting the redox transformation of the NO* intermediate to nitrate. However, too much RuO2 in the catalyst is detrimental to both the selectivity of the NOR and the Faradaic efficiency due to the dominant OER process. Experimentally, a considerable nitrate yield rate of 161.9 µmol h−1 gcat−1 (besides, a total nitrate yield of 47.9 µg during 50 h) and a highest nitrate Faradaic efficiency of 26.1% are achieved by the Ru/TiO2 catalyst (with the hybrid composition of RuxTiyO2 and extra RuO2 by 2.79 wt% Ru addition amount) in 0.1 m Na2SO4 electrolyte.

The oxygen evolution reaction (OER) is a key process involved in energy and environment‐related technologies. An ideal OER electrocatalyst should show high exposure of active sites and optimal adsorption energies of oxygenated species. However, earth‐abundant transition‐metal‐based OER electrocatalysts still operate with sluggish OER kinetics. Here, a cation‐exchange route is reported to fabricate cobalt‐vanadium‐iron (oxy)hydroxide (CoV‐Fe0.28) nanosheets with tunable binding energies for the oxygenated intermediates. The formation of an amorphous/crystalline heterostructure in the CoV‐Fe0.28 catalyst boosts the exposure of active sites compared to their crystalline and amorphous counterparts. Furthermore, the synergetic interaction of Co, V, and Fe cations in the CoV‐Fe0.28 catalyst subtly regulates the local coordination environment and electronic structure, resulting in the optimal thermodynamic barrier for this elementary reaction step. As a result, the CoV‐Fe0.28 catalyst exhibits superior electrocatalytic activity toward the OER. A low overpotential of 215 mV is required to afford a current density of 10 mA cm−2 with a small Tafel slope of 39.1 mV dec−1, which outperforms commercial RuO2 (321 mV and 86.2 mV dec−1, respectively).

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promising alternative to fossil fuels. Water electrolysis by renewable resourcederived electricity represents a facile and green route to produce H 2. [1-13] Generally, the key to implement high-performance water splitting is to develop economically viable, efficient, and robust electrocatalysts to lower the activation potential barriers. Thus far, researchers have devoted extensive enthusiasm to the investigation of electrocatalysts. Currently, most efforts have been taken on the search for new materials, [14-16] regulation of morphology, [17] crystallinity, [18] facet, [19] component, [20-24] defect, [25,26] matter phase, [27,28] or the compositing of various materials with synergy. [29-36] However, the performances of emerging nonnoble electrocatalysts still lag behind those of noble ones. To address this issue, researchers have turned their attention beyond the electrocatalysts themselves. Field-assisted electrocatalysis is the electrocatalytic reaction proceeded in the presence of a field. It represents a promising methodology since it exerts an additional degree of freedom to engineer an electrochemical process. Inspiringly, indisputable improvements in electrocatalytic hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) have been implemented with the assist of various fields, including electric field, magnetic field, strain, and light. For example, the electrocatalytic HER of a MoS 2 nanosheet is markedly boosted by simply exploiting a back gate voltage of 5 V. [37] Its overpotential at −100 mA cm −2 is decreased from 240 to 38 mV. In addition, enhancement of alkaline water electrolysis is achieved by applying a moderate magnetic field (≤450 mT) to an electrocatalytic anode consists of highly magnetic electrocatalysts. [38] Its current density increments are beyond 100%. Furthermore, the HER activity of β-PdH x increases monotonically as the applied strain increases from 0% to 4.5%. [39] Lastly, an approximately threefold increase in current density of Au-MoS 2 for electrocatalytic HER is realized upon the illumination of IR light. [40] These results undoubtedly elucidate that applying a field during electrocataly sis opens up great opportunities toward further improving electrocatalytic activity. Moreover, this approach provides merits of facile, dynamical, continuous, reversible, and universal control. Despite fascinating achievements, these investigations are relatively scattered. The underneath mechanisms and principles Hydrogen fuel is considered as one of the most clean renewable resources, warranting it a primary alternative to fossil fuels for future energy supplies. Electrocatalytic water splitting is an eco-friendly technique for high-purity hydrogen production. However, the sluggish dynamics of its two halfreactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), are tough challenges impeding the practical application of this technology. In these years, external field-assisted HER and OER have attracted extensive research interests. Herein, the effects o...