Interfacial solar evaporation, which captures solar energy and localizes the absorbed heat for water evaporation, is considered a promising technology for seawater desalination and solar energy conversion. However, it is currently limited by its low photothermal conversion efficiency, salt accumulation, and poor reliability. Herein, inspired by human intestinal villi structure, we design and fabricate a novel intestinal villi-like nitrogen-doped carbon nanotubes solar steam generator (N-CNTs SSG) consisting of three-dimensional (3D) hierarchical carbon nanotube matrices for ultrahigh solar evaporation efficiency. The 3D matrices with radial direction nitrogen-doped carbon nanotube clusters achieve ultrahigh surface area, photothermal efficiency, and hydrophilicity, which significantly intensifies the whole interfacial solar evaporation process. The new solar evaporation efficiency reaches as high as 96.8%. Furthermore, our ab initio molecular dynamics simulation reveals that N-doped carbon nanotubes exhibit a greater number of electronic states in close proximity to the Fermi level when compared to pristine carbon nanotubes. The outstanding absorptivity in the full solar spectrum and high solar altitude angles of the 3D hierarchical carbon nanotube matrices offer great potential to enable ultrahigh photothermal conversion under all-day and all-season circumstances.

Carbon fibers (CFs) with notable comprehensive properties, such as light weight, high specific strength, and stiffness, have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications. However, the commonly utilized precursors, such as polyacrylonitrile and pitch, exhibit a lack of environmental sustainability, and their costs are heavily reliant on fluctuating petroleum prices. To meet the substantial market demand for CFs, significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass. Lignin, the most abundant polyphenolic compound in nature, is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature, low cost, high carbon content, and aromatic structures. Nevertheless, the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products, which are diverse and heterogeneous in nature, restricting the industrialization of lignin-derived CFs. This review classifies fossil-derived and biomass-derived CFs, starting from the sources and chemical structures of raw lignin, and outlines the preparation methods linked to the performance of lignin-derived CFs. A comprehensive discussion is presented on the relationship between the structural characteristics of lignin, spinning preparation, and structure-morphology-property of lignin-derived CFs. Additionally, the potential applications of these materials in various domains, including energy, catalysis, composites, and other advanced products, are also described with the objective of spotlighting the unique merits of lignin. Finally, the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.

Solar-driven carbon dioxide reduction reaction (CO₂RR) provides an opportunity to produce value-added chemical feedstocks and fuels. However, achieving efficient and stable photoelectrochemical (PEC) CO₂RR into selective products is challenging owing to the difficulties associated with the optical and the electrical configuration of PEC devices and electrocatalyst properties. Herein, we construct an efficient, concentrated sunlight-driven CO₂RR setup consisting of InGaP/GaAs/Ge triple-junction cell as a photoanode and oxide-derived Au (Ox-Au) as a cathode to perform the unassisted PEC CO₂RR. Under one-sun illumination, a maximum operating current density of 11.5 mA cm^–2 with an impressive Faradaic efficiency (FE) of ~98% is achieved for carbon monoxide (CO) production, leading to a solar-to-fuel conversion efficiency of ~15%. Under concentrated intensity of 10 sun, the photoanode records a maximum current density of ~124 mA cm^–2 and maintains ~60% of FE for CO production. The results demonstrate crucial advancements in using III–V based photoanodes for concentrated PEC CO₂RR.

As a potential substitute for traditional nonaqueous organic electrolytes, polymer-based solid-state electrolytes (SSEs) have the advantages of high safety, flexibility, low density, and easy processing. In contrast, they still face challenges, such as low room-temperature ionic conductivity, narrow electrochemical windows, and poor mechanical strength. To realize the practical application of all-solid-state alkali metal ion batteries, there has been a lot of research on modifying the chemical composition or structure of polymer-based SSEs. In this review, the transport mechanism of alkali metal ions in polymer SSEs is briefly introduced. We systematically summarize the recent strategies to improve polymer-based SSEs, which have been validated in lithium-ion batteries and sodium-ion batteries, including lamellar electrolyte structure, dual salts hybridization, oriented filler alignment, and so on. Then, taking the unique properties of potassium metal and potassium ions into consideration, the feasibility of potassium-ion batteries for practical use enabled by these novel modification methods is discussed.

Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds, but it is limited by the difficulty of designing efficient catalysts and lack of understanding the mechanism of catalysis. Herein, we demonstrate a novel strategy by generation of oxyhydroxide layers on two-dimensional iron-doped layered nickel phosphorus trisulfides (Ni_1−xFe_xPS₃) during the oxidation of benzylamine (BA). In-depth structural and surface chemical characterizations during the electrocatalytic process combined with theoretical calculations reveal that Ni_(1−x)Fe_xPS₃ undergoes surface reconstruction under alkaline conditions to form the metal oxyhydroxide/phosphorus trichalcogenide (NiFeOOH/Ni_1−xFe_xPS₃) heterostructure. Interestingly, the generated heterointerface facilitates BA oxidation with a low onset potential of 1.39 V and Faradaic efficiency of 53% for benzonitrile (BN) synthesis. Theoretical calculations further indicate that the as-formed NiFeOOH/Ni_1−xFe_xPS₃ heterostructure could offer optimum free energy for BA adsorption and BN desorption, resulting in promising BN synthesis.

The rise of Zn-ion hybrid capacitor (ZHC) has imposed high requirements on carbon cathodes, including reasonable configuration, high specific surface area, multiscale pores, and abundant defects. To achieve this objective, a template-oriented strategy coupled with multi-heteroatom modification is proposed to precisely synthesize a three-dimensional boron/nitrogen-rich carbon nanoflake-interconnected micro/nano superstructure, referred to as BNPC. The hierarchically porous framework of BNPC shares short channels for fast Zn²⁺ transport, increased adsorption-site accessibility, and structural robustness. Additionally, the boron/nitrogen incorporation effect significantly augments Zn²⁺ adsorption capability and more distinctive pseudocapacitive nature, notably enhancing Zn-ion storage and transmission kinetics by performing the dual-storage mechanism of the electric double-layer capacitance and Faradaic redox process in BNPC cathode. These merits contribute to a high capacity (143.7 mAh g⁻¹ at 0.2 A g⁻¹) and excellent rate capability (84.5 mAh g⁻¹ at 30 A g⁻¹) of BNPC-based aqueous ZHC, and the ZHC still shows an ultrahigh capacity of 108.5 mAh g⁻¹ even under a high BNPC mass loading of 12 mg cm⁻². More critically, the BNPC-based flexible device also sustains notable cyclability over 30,000 cycles and low-rate self-discharge of 2.13 mV h⁻¹ along with a preeminent energy output of 117.15 Wh kg⁻¹ at a power density of 163.15 W kg⁻¹, favoring a creditable applicability in modern electronics. In/ex-situ analysis and theoretical calculations elaborately elucidate the enhanced charge storage mechanism in depth. The findings offer a promising platform for the development of advanced carbon cathodes and corresponding electrochemical devices.

This study demonstrates the electrochemical reduction of carbon monoxide (COR) at high current densities in a zero-gap electrolyzer cell and cell stack. By systematically optimizing both the commercially available membrane electrode assembly components (including binder content and gas diffusion layer) and the operating conditions, we could perform COR at current densities up to 1.4 A cm⁻² with a maximum C₂₊ selectivity of 90%. We demonstrated the scale-up to a 3 × 100 cm² electrolyzer stack that can sustain stable operation at 1 A cm⁻² for several hours without significant performance decay and with a total C₂₊ selectivity of ~80% and an ethylene selectivity of ~40%. We provide critical insights into the holistic optimization of key system parameters, without using special catalysts or surface additives, which can pave the way for scalable and industrially viable COR processes.

Photocatalytic transformation of biomass into biofuels and value-added chemicals is of great significance for carbon neutrality. Metal-free carbon nitride has extensive applications but with almost no absorption and utilization of near-infrared light, accounting for 50% of sunlight. Here, a molten salt-assisted in-plane “stitching” and interlayer “cutting” protocol is developed for constructing a highly crystalline carbon nitride catalyst containing structural oxygen (HC-CN). HC-CN is highly efficient for the photothermal cascade transformation of biomass-derived glucose into lactic acid (LA) with an unprecedented yield (94.3%) at 25°C under full-spectrum light irradiation within 50 min, which is also applicable to quantitatively photo-upgrading various saccharides. Theoretical calculations expound that the light-induced glucose-to-catalyst charge transfer can activate the C_β–H bond to promote the rate-determining step of intramolecular hydrogen shift in glucose-to-fructose isomerization. Meanwhile, the introduced structural oxygen in HC-CN can not only facilitate the local electric field formation to achieve rapid charge transport/separation and regulate selective •O₂⁻ generation for oriented C3–C4 bond cleavage of fructose but also narrow the energy band gap to broaden the light absorption range of HC-CN, contributing to enhanced LA production without exogenous heating. Moreover, HC-CN is highly recyclable and exhibits negligible environmental burden and low energy consumption, as disclosed by the life cycle assessment. Tailored construction of full-spectrum light adsorption and versatile reaction sites provides a reference for implementing multi-step biomass and organic conversion processes under mild conditions.

MXenes, an innovative class of two-dimensional (2D) materials composed of transition-metal carbides and/or nitrides, have garnered significant interest for their potential in energy storage and conversion applications, which is largely attributed to their modifiable surface terminations, exceptional conductivity, and favorable hydrophilic characteristics. MXenes show various ion transport behaviors in applications like electrochemical catalysis, supercapacitors, and batteries, encompassing processes like electrostatic adsorption of surface ions, redox reactions of ions, and interlayer ion shuttle. This review aims to present a summary of advancements in the comprehension of ion transport behaviors of Ti₃C₂T_x MXenes. First, the composition, properties, and synthesis techniques of MXenes are concisely summarized. Subsequently, the discussion delves into the mechanisms of ion transport in MXenes during CO₂ reduction, water splitting, supercapacitor operation, and battery performance, elucidating the factors determining the electrochemical behaviors and efficacy. Furthermore, a compilation of strategies used to optimize ion transport behaviors in MXenes is presented. The article concludes by presenting the challenges and opportunities for these fields to facilitate the continued progress of MXenes in energy-related technologies.

The electrocatalytic water-splitting process is widely acknowledged as the most sustainable and environmentally friendly technology for hydrogen (H₂) production. However, its energy efficiency is significantly constrained by the kinetically slow oxygen evolution reaction (OER) at the anode, which accounts for about 90% of the electrical energy consumption in the water-splitting process. A new strategy is urgently needed to reduce its energy consumption. In recent years, electrochemical oxidation of small molecules has been considered for replacement of OER for efficient H₂ production, due to its benign operational conditions, low theoretical thermodynamic potential, high conversion efficiency and selectivity, and environmental sustainability. Hybrid electrolysis systems, by integrating cathodic hydrogen evolution reaction with anodic oxidation of small molecules, have been introduced, which can generate high-purity H₂ and produce value-added products or pollutant degradation. In this review, we highlight the recent advancements and significant milestones achieved in hybrid water electrolysis systems. The focus is on non-noble metal electrocatalysts, reaction mechanisms, and the construction of electrolyzers. Additionally, we present the prevailing challenges and future perspectives pertinent to the evolution of this burgeoning technology.

To achieve the target of carbon neutrality, it is crucial to develop an efficient and green synthesis methodology with good atomic economy to achieve sufficient utilization of energy and sustainable development. Photoinduced electron transfer reversible addition–fragmentation chain-transfer (PET-RAFT) polymerization is a precise methodology for constructing polymers with well-defined structures. However, conventional semiconductor-mediated PET-RAFT polymerization still has considerable limitations in terms of efficiency as well as the polymerization environment. Herein, sulfur-doped carbonized polymer dots (CPDs) were hydrothermally synthesized for catalysis of aqueous PET-RAFT polymerization at unprecedented efficiency with a highest propagation rate of 5.05 h⁻¹. The resulting polymers have well-controlled molecular weight and narrow molecular weight dispersion (Ð < 1.10). Based on the optoelectronic characterizations, we obtained insights into the photoinduced electron transfer process and proposed the mechanism for CPD-mediated PET-RAFT polymerization. In addition, as-synthesized CPDs for PET-RAFT polymerization were also demonstrated to be suitable for a wide range of light sources (blue/green/solar irradiation), numerous monomers, low catalyst loading (low as 0.01 mg mL⁻¹), and multiple polar solvent environments, all of which allowed to achieve efficiencies much higher than those of existing semiconductor-mediated methods. Finally, the CPDs were confirmed to be non-cytotoxic and catalyzed PET-RAFT polymerization successfully in cell culture media, indicating broad prospects in biomedical fields.

As the next generation of advanced energy storage devices, aqueous Zn ions batteries (AZIBs) still face many challenges, especially dendrites on the Zn metal anode and side reactions. Although an interface modification strategy has been applied to optimize the stability of Zn metal anodes and has shown some improvement, they are still far from meeting the requirements for practical applications. There is a lack of consideration for designing a multifunctional solid electrolyte interphase (SEI) which modifies the solvation/desolvation structure of Zn ion at the interface of Zn metal anodes. Herein, we constructed an amphiphilic SEI with hydrophilic and hydrophobic properties: N, S dual-doped graphene quantum dots (GQDs). The N, S dual-doped GQDs have been synthesized using a one-step hydrothermal approach and were utilized for Zn anode surface modification. When regulating the solvation structure of the Zn ion interface by N, S dual-doped GQDs, it also promotes its desolvation kinetics, optimizes the interfacial behavior of Zn ion deposition to prohibit Zn dendrite growth, and suppresses side reactions in the Zn anode surface. The Zn|Zn symmetric cell has achieved a long cycle life of more than 800 h at 5 mA cm⁻². The Zn|V₂O₅ battery has achieved an excellent performance of more than 80% capacity retention after 1400 cycles at 1 A g⁻¹. This provides another novel and cost-effective path for the SEI design of aqueous Zn-ion batteries.