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Replacing oxygen evolution reaction (OER) by electrooxidations of organic compounds has been considered as a promising approach to enhance the energy conversion efficiency of the electrolytic water splitting proces. Developing efficient electrocatalysts with low potentials and high current densities is crucial for the large‐scale productions of H2 and other value‐added chemicals. Herein, non‐noble metal electrocatalysts Co‐doped Ni3S2 self‐supported on a Ni foam (NF) substrate are prepared and used as catalysts for 5‐hydroxymethylfurfural (HMF) oxidation reaction (HMFOR) under alkaline aqueous conditions. For HMFOR, the Co0.4NiS@NF electode achieves an extremely low onset potential of 0.9 V versus reversible hydrogen electrode (RHE) and records a large current density of 497 mA cm–2 at 1.45 V versus RHE for HMFOR. During the HMFOR‐assisted H2 production, the yield rates of 2,5‐furandicarboxylic acid (FDCA) and H2 in a 10 mL electrolyte containing 10 × 10−3 M HMF are 330.4 µmol cm–2 h–1 and 1000 µmol cm–2 h–1, respectively. The Co0.4NiS@NF electrocatalyst displays a good cycling durability toward HMFOR and can be used for the electrooxidation of other biomass‐derived chemicals. The findings present a facile route based on heteroatom doping to fabricate high‐performance catalyses that can facilitate the industrial‐level H2 production by coupling the conventional HER cathodic processes with HMFOR. A facile route based on in‐situ heteroatom doping was developed to fabricate Co‐doped Ni3S2 electrocatalysts on Ni foam (NF) substrates. The optimized electrocatalyst (Co0.4NiS@NF) electrode requires an extremely low onset potential and records a high current density for the 5‐hydroxymethylfurfural (HMF) oxidation reaction (HMFOR) and facilitates the industrial‐level H2 production by coupling the conventional HER cathodic process with HMFOR.

The scarcity of wettability, insufficient active sites, and low surface area of graphite felt (GF) have long been suppressing the performance of vanadium redox flow batteries (VRFBs). Herein, an ultra‐homogeneous multiple‐dimensioned defect, including nano‐scale etching and atomic‐scale N, O co‐doping, was used to modify GF by the molten salt system. NH4Cl and KClO3 were added simultaneously to the system to obtain porous N/O co‐doped electrode (GF/ON), where KClO3 was used to ultra‐homogeneously etch, and O‐functionalize electrode, and NH4Cl was used as N dopant, respectively. GF/ON presents better electrochemical catalysis for VO2+/VO2+ and V3+/V2+ reactions than only O‐functionalized electrodes (GF/O) and GF. The enhanced electrochemical properties are attributed to an increase in active sites, surface area, and wettability, as well as the synergistic effect of N and O, which is also supported by the density functional theory calculations. Further, the cell using GF/ON shows higher discharge capacity, energy efficiency, and stability for cycling performance than the pristine cell at 140 mA cm−2 for 200 cycles. Moreover, the energy efficiency of the modified cell is increased by 9.7% from 55.2% for the pristine cell at 260 mA cm−2. Such an ultra‐homogeneous etching with N and O co‐doping through “boiling” molten salt medium provides an effective and practical application potential way to prepare superior electrodes for VRFB. An ultra‐homogeneous modification was used for multiple‐dimensioned defect engineering of graphite felt electrodes for a vanadium redox flow battery. Graphite felt obtains nano‐scale etching and atom‐scale N/O co‐doping. The electrode offers a larger surface area, more active sites, and better hydrophilicity for both VO2+/VO2+ and V3+/V2+ redox reactions. The cell using a modified electrode further shows lower polarization and higher energy efficiency.

Direct recycling has been regarded as one of the most promising approaches to dealing with the increasing amount of spent lithium‐ion batteries (LIBs). However, the current direct recycling method remains insufficient to regenerate outdated cathodes to meet current industry needs as it only aims at recovering the structure and composition of degraded cathodes. Herein, a nickel (Ni) and manganese (Mn) co‐doping strategy has been adopted to enhance LiCoO2 (LCO) cathode for next‐generation high‐performance LIBs through a conventional hydrothermal treatment combined with short annealing approach. Unlike direct recycling methods that make no changes to the chemical composition of cathodes, the unique upcycling process fabricates a series of cathodes doped with different contents of Ni and Mn. The regenerated LCO cathode with 5% doping delivers excellent electrochemical performance with a discharge capacity of 160.23 mAh g−1 at 1.0 C and capacity retention of 91.2% after 100 cycles, considerably surpassing those of the pristine one (124.05 mAh g−1 and 89.05%). All results indicate the feasibility of such Ni–Mn co‐doping‐enabled upcycling on regenerating LCO cathodes. Ni–Mn co‐doping is introduced to upcycle spent LiCoO2 (LCO) material through an improved hydrothermal treatment coupled with short annealing approach. The 5% Ni–Mn co‐doped material outperforms the pristine LCO material with an initial specific capacity of ~160 mAh g−1 under a cut‐off potential of 4.35 V and ~91% capacity retention after 100 cycles.

(Sm, Co) co-doped ZnO nanoparticles (Zn 1−2x Sm x Co x O), 0.00 ≤ x ≤ 0.06 , have been prepared by the co-precipitation technique. The effect of the dopant ions Sm 3+ and Co 2+ on the structural, morphological, and electrical conductivity of ZnO has been studied. XRD analysis shows the substitution of Zn 2+ ions by the co-doping Sm 3+ and Co 2+ ions with the formation of secondary phases as Sm 2 O 3 and Co 3 O 4 upon 0.005 co-doping and above. Raman spectra showed the characteristic mode of the wurtzite structure of ZnO nanoparticles with a vibration assigned to the bound of Co with the donor defects at high doping level of (Sm, Co). The spherical morphology of pure ZnO is transformed into nanorods as the concentration of Sm 3+ and Co 2+ increases. From EDX spectra, it was shown that all samples exhibit an excellent compositional homogeneity that verifies the Sm and Co presence as real dopants in ZnO crystalline structure. FTIR spectra show one discrete peak at 417 cm −1 with another broad peak at 568 cm −1 corresponding to Zn–O stretching, which confirms the formation of the wurtzite structure of the samples. Photoluminescence studies reveal the existence of minor defects in the co-doped samples. The study proposes the suitable use of the samples in the high-efficiency UV light-emitting devices due to the intense UV peaks compared with the lower visible peaks. The excitation dependent PL spectra demonstrated a redshift with increasing the excitation wavelength accounting for the distribution of energetic species in the ground state. The DC electrical conductivity is enhanced with (Sm, Co) co-doping of x = 0.1 due to the formation of thermally activated donor levels.

The development of simple and effective strategies to prepare electrocatalysts, which possess unique and stable structures comprised of metal/nonmetallic atoms for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is currently an urgent issue. Herein, an efficient bifunctional electrocatalyst featured by ultralong N, S‐doped carbon nano‐hollow‐sphere chains about 1300 nm with encapsulated Co nanoparticles (Co‐CNHSCs) is developed. The multifunctional catalytic properties of Co together with the heteroatom‐induced charge redistribution (i.e., modulating the electronic structure of the active site) result in superior catalytic activities toward OER and ORR in alkaline media. The optimized catalyst Co‐CNHSC‐3 displays an outstanding electrocatalytic ability for ORR and OER, a high specific capacity of 1023.6 mAh gZn−1, and excellent reversibility after 80 h at 10 mA cm−2 in a Zn‐air battery system. This work presents a new strategy for the design and synthesis of efficient multifunctional carbon‐based catalysts for energy storage and conversion devices. An ultralong N,S co‐doped carbon nano‐hollow‐sphere chain with encapsulated Co nanoparticles (Co‐CNHSC) is synthesized as a bifunctional catalyst for both the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) by adopting a one‐step pyrolysis method. Benefiting from the electronic structure modulation between metal and nonmetal species, the optimized Co‐CNHSC‐3 exhibits an excellent bifunctional activity for OER and ORR and also shows superior performance for Zn‐air batteries.

Herein, Ni²⁺–Al³⁺ co-doped Co 0.6−x Zn 0.4−x Ni x Al x Fe 2 O 4 (0 ≤ x ≤ 0.08) nanoferrites were synthesized via a co-precipitation route to elucidate the role of defect engineering and cation redistribution in tuning optical magneto-structural properties. X-ray diffraction (XRD) confirmed single-phase cubic spinel formation with slight lattice expansion (8.3667–8.374 Å) accompanied by crystallite size reduction (16.27–11.33 nm). HRTEM and SAED analyses revealed spherical/cubic nanoparticles with high crystallinity and lattice coherence, consistent with XRD results. The increase in microstrain and dislocation density indicates enhanced lattice distortion induced by substitution. XPS analysis revealed mixed Fe²⁺/Fe³⁺ states distributed over tetrahedral and octahedral sites, enabling quantitative cation distribution modeling. The pronounced enhancement of the Raman A 1g mode confirms progressive tetrahedral distortion and cation rearrangement. The nanoferrites exhibit soft magnetic behavior with high saturation magnetization (51–58 emu/g) and low coercivity (20–79 Oe). The law of approach to saturation (LAS) analysis reveals a marked decrease in the anisotropy constant, primarily attributed to the dilution of octahedral Co²⁺ ions, reinforced by Al³⁺-induced A–B exchange weakening and nanoscale spin canting. These findings demonstrate that controlled multi-cation substitution provides an effective strategy for tailoring magnetic softness and anisotropy, making the materials promising for spintronics, high-frequency electronics, magnetic sensing, and electromagnetic interference shielding applications.

Ion doping is an effective strategy for achieving high‐performance flexible Cu2ZnSn(S,Se)4 (CZTSSe) solar cells by defect regulations. Here, a Li&Na co‐doped strategy is applied to synergistically regulate defects in CZTSSe bulks. The quality absorbers with the uniformly distributed Li and Na elements are obtained using the solution method, where the acetates (LiAc and NaAc) are as additives. The concentration of the harmful CuZn anti‐site defects is decreased by 8.13% after Li incorporation, and that of the benign NaZn defects is increased by 36.91% after Na incorporation. Synergistic Li&Na co‐doping enhances the carrier concentration and reduces the interfacial defects concentration by one order of magnitude. As a result, the flexible CZTSSe solar cell achieves a power conversion efficiency (PCE) of 10.53% with certified 10.12%. Because of the high PCE and the homogeneous property, the Li&Na co‐doped device is fabricated to a large area (2.38 cm2) and obtains 9.41% PCE. The co‐doping investigation to synergistically regulate defects provides a new perspective for efficient flexible CZTSSe solar cells. The Li&Na co‐doped strategy is applied to synergistically regulate defects in CZTSSe bulks using the cheap and non‐toxic LiAc and NaAc as additives. The synergistic co‐doping effectively passivates harmful defects and increases shallow‐level defects. The flexible CZTSSe device achieves 10.53% efficiency (certified 10.12%) in the area (0.21 cm2) and 9.41% efficiency in large area (2.38 cm2).

Inorganic perovskite CsPbI3 solar cells hold great potential for improving the operational stability of perovskite photovoltaics. However, electron extraction is limited by the low conductivity of TiO2, representing a bottleneck for achieving stable performance. In this study, a co‐doping strategy for TiO2 using Nb(V) and Sn(IV), which reduces the material's work function by 80 meV compared to Nb(V) mono‐doped TiO2, is introduced. To gain fundamental understanding of the processes at the interfaces between the perovskite and charge‐selective layer, transient surface photovoltage measurements are applied, revealing the beneficial effect of the energetic and structural modification on electron extraction across the CsPbI3/TiO2 interface. Using 2D drift‐diffusion simulations, it is found that co‐doping reduces the interface hole recombination velocity by two orders of magnitude, increasing the concentration of extracted electrons by 20%. When integrated into n–i–p solar cells, co‐doped TiO2 enhances the projected TS80 lifetimes under continuous AM1.5G illumination by a factor of 25 compared to mono‐doped TiO2. This study provides fundamental insights into interfacial charge extraction and its correlation with operational stability of perovskite solar cells, offering potential applications for other charge‐selective contacts. TiO2 is highly relevant in photoelectrochemistry, (photo)catalysis, and sensor applications, where high conductivity is crucial. Herein, a co‐doping strategy for TiO2 using Nb(V) and Sn(IV) is developed, enhancing electron extraction from perovskite and improving solar cell efficiency and stability. Using transient surface photovoltage and drift‐diffusion simulations, buried interfaces are characterized and critical charge transport parameters for optoelectronic advancements are extracted.

Nonmetallic co-doping and surface hole construction are simple and efficient strategies for improving the photocatalytic activity and regulating the electronic structure of g-C3N4. Here, the g-C3N4 catalysts with B-F or B-S co-doping combined with nitrogen vacancies (Nv) are designed. Compared to the pristine g-C3N4, the direction of the excited electron orbit for the B-F-co-doped system is more matching (N2pz→C2pz), facilitating the separation of electrons and holes. Simultaneously, the introduced nitrogen vacancy can further reduce the bandgap by generating impurity states, thus improving the utilization rate of visible light. The doped S atoms can also narrow the bandgap of the B-S-Nv-co-doped g-C3N4, which originates from the p-orbital hybridization between C, N, and S atoms, and the impurity states are generated by the introduction of N vacancies. The doping of B-F-Nv and B-S-Nv exhibits a better CO2 reduction activity with a reduced barrier for the rate-determining step of around 0.2 eV compared to g-C3N4. By changing F to S, the origin of the rate-determining step varies from *CO2→*COOH to *HCHO→*OCH3, which eventually leads to different products of CH3OH and CH4, respectively.

The rational construction of Ti3C2Tx MXene‐based composites has been deemed as a popular way to improve their electrochemical energy storage performances owing to the unique two‐dimensional (2D) structure, excellent conductivity, and good flexibility. However, it remains a major challenge to assemble mesoporous carbon onto Ti3C2Tx with fewer oxygen‐containing groups by using surfactants with short hydrophilic segments. In the work, we propose a molecular engineering assembly strategy for the growth of N,P co‐doped mesoporous carbon onto Ti3C2Tx nanosheets (NPMC/Ti3C2Tx) under the assistance of phytic acid by using melamine‐formaldehyde resin and pluronic P123 (PEO20PPO70PEO20) as the carbon/nitrogen source and soft template, respectively. The detailed investigations reveal that phytic acid with abundant hydroxyl groups can effectively enhance the hydrogen bond interactions among P123, carbon precursor, and Ti3C2Tx nanosheets, thus ensuring the efficient assembly of mesoporous carbon onto Ti3C2Tx. The obtained NPMC/Ti3C2Tx composite demonstrates a set of merits, including cylindrical mesopore, N,P co‐doping, and a good combination of mesoporous carbon and Ti3C2Tx nanosheets. As a result, it exhibits an improved lithium‐ion storage performance, delivering a high reversible capacity of 556.3 mA h g−1 after 100 cycles at 0.1 A g−1. The present work provides a feasible molecular engineering assembly route for the rational design of high‐performance Ti3C2Tx MXene‐based electrodes. A molecular engineering assembly strategy has been proposed for assembling the N, P co‐doped mesoporous carbon onto 2D Ti3C2Tx nanosheets with the assistance of phytic acid. The delicate design endows the as‐made NPMC/Ti3C2Tx anode with an enhanced lithium‐ion storage performance.