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Touch panels are extensively applied across various fields, serving as a critical platform for the future of human-machine interaction and the metaverse. However, touch panel development is impeded by complicated sensor systems, including electrode grids, stacked multilayers, and external power. Here, a highly sensitive self-powered vibration sensor based on the triboelectric nanogenerator (VS-TENG) is designed to realize grid-free touch recognition on arbitrary surfaces by detecting and locating an external vibration source. The VS-TENG adopts a sensing structure composed of a dual-layer copper electrode designed with a parametric surface and a fluorinated ethylene propylene (FEP) film, enabling the detection of vibrations within the frequency range of 1–4500 Hz and sub-micron low-amplitude vibrations. The dual-layer electrode structure is beneficial to resist the interference from external environment. The output performance of the VS-TENG under various vibration frequencies, amplitudes, and directions, as well as its sensing capabilities when installed on panels of different materials and shapes, are systematically analyzed. The touch panel based on the VS-TENG can easily rearrange the touch resolution according to given scenarios without any physical modification to the sensor, enabling game control and vivid handwriting. This highlights its significant potential for diverse applications in the future metaverse. [Display omitted] • The VS-TENG's inner surface is parametrically designed to detect vibrations from 1-4500 Hz and sub-micron amplitudes. • The VS-TENG's dual-layer electrode design resists external interference and maintains stable performance at various angles. • Installing VS-TENGs on arbitrary panels enables excellent touch resolution through vibration signals. [ABSTRACT FROM AUTHOR]

• Aerogels can be easily fabricated via cross-linking vermiculite and MXene. • The pore structures and surface compositions of aerogels can be finely tuned. • Monolithic aerogel has excellent CO 2 storing capacity by boosted hydrate formation. • Degree of water saturation plays the most vital role in hydrate formation. Gas hydrate provides an ideal way for CO 2 capture and storage using water by forming cages via an environment-friendly and energy-efficient hydrate formation process. However, the practical utilization and upscaling of hydrate-based gas storage are impeded by the slow formation kinetics of gas hydrate due to the limited multiphase interface for mass transfer and reaction. Herein, we demonstrated a simple strategy to fabricate composite aerogels assembled of natural vermiculite and MXene nanosheets as the ideal substrate for boosting CO 2 hydrate formation. The structure and surface compositions of vermiculite/MXene composite aerogels were analyzed by XRD, FT-IR, SEM, and XPS. It shows that monolithic pore structures and surface functional groups can be finely tuned by controlling the mass ratio of vermiculite and MXene, leading to an outstanding CO 2 storage capacity of 136.9 v/v (corresponding to 0.121 mol CO 2 /mol water) with enhanced hydrate formation kinetics. The degree of water saturation plays the most vital role in controlling formation kinetics and gas storage capacity. This work provides a reliable method to synthesize aerogels for boosting CO 2 storage via enhanced hydrate formation and sheds light on the structure performance relationship of porous materials for enhancing gas hydrate formation. [ABSTRACT FROM AUTHOR]

• Aerogels with tunable surface properties significantly promoted hydrate formation. • C O and –OH were found to dominate nucleation and growth of hydrate. • The finely tuned oxygen-containing groups lead to the enhanced kinetics. • Aerogels exhibit high storage capacity and excellent cycling stability. • Aerogels can be prepared in a large scale for hydrate-based applications. Gas hydrate, composed of water molecule cages, is promising for safe and sustainable gas storage with minor energy consumption. However, the practical utilization of hydrate-based technologies is hindered by the sluggish formation kinetics of gas hydrate. Central to the challenge of utilizing hydrate-based gas storage is developing effective promoters and improving the understanding of the complicated interplay between a promoter's structure and chemical composition. Herein, we reported a simple and scalable strategy to produce pyrolytic composite aerogels assembled from vermiculite nanosheets and sodium alginate as efficient promoters for the methane hydrate formation. Benefiting from the high specific surface area and finely tuned surface functional groups, the as-made aerogels significantly improve methane hydrate formation kinetics with high storage capacity and excellent cycling stability. It is found that the phase change process of water to methane hydrate conversion can be controlled by adjusting the content of carbonyl and hydroxyl groups of the as-made aerogels. Raman spectra were used to elucidate the molecular mechanisms for the enhanced methane hydrate formation due to the interaction between oxygen-containing surface functional groups and water molecules close to used aerogels. This work not only provides an effective way to fabricate aerogel-based promoters for methane hydrate formation but also sheds light on the underlying mechanism of the surface composition dependent performance for improving gas hydrate formation. [ABSTRACT FROM AUTHOR]

Self-assembly of two-dimensional (2D) nanosheets into three-dimensional (3D) aerogels, can solve the problems of recovery and re-stacking, and fully utilize the potential of high specific surface areas and easily accessible surface sites. However, organic binders have to be added to fabricate aerogels using 2D nanosheets as building blocks, which inevitably limit the performance of 2D nanosheets due to covered surfaces. Herein, we proposed a new strategy to fabricate vermiculite aerogels (VAs) assembled from delaminated vermiculite nanosheets (VNSs) via metal ion induced fast gelation. The cheap and earth-abundant vermiculite was used as the raw materials to produce high-quality nanosheets by high speed shear-mixing. VNSs with a concentration as high as 15 mg/mL were produced. The concentration-dependent gelation performance was studied and showed a critical concentration of 6 mg/mL for gelation and fabricating monolithic aerogels without cracks. It is also found metal ions played critical roles in formation mechanically stable and robust aerogels with trivalent cations, particularly Al3+ being most effective. The edge-surface intertwining VNSs induced by the Al3+ cross-linking endow the VAs good mechanical strength and excellent environmental stability. As fixed adsorbent beds, the VAs show promising performance in fast removing organic dyes from water due to the developed pore structures, large specific surface area, and exposed surface sites. [Display omitted] • Vermiculite aerogels were successfully assembled using a fast and scalable method. • Both nanosheet concentration and the ion type play critical roles in gelation. • Vermiculite aerogels have shown excellent performance in removing organic dyes. [ABSTRACT FROM AUTHOR]

With the rapid development of agriculture, controlling phosphorus emissions is a pressing challenge for preventing water eutrophication. A graphite-promoted cyclopentane (CP) hydrate-based desalination was proposed to remove K 3 PO 4 from effluents. It was found via the in situ optical microscopy that the reaction temperature and the concentration of feeding K 3 PO 4 solution significantly affect the morphologies and amount of the as-produced CP hydrate crystals. The lower reaction temperature produces more crystals with irregular shapes, while fewer crystals formed in K 3 PO 4 solution with higher concentration. The reaction temperature, time and feeding concentration-dependent desalination and salt enrichment performances were studied. It was found that desalination efficiency linearly increases with the elevated reaction temperature ranging from − 2 °C to 3 °C; however, water recovery declines with temperature. The temperature-dependent water recovery is due to the strong driving force for hydrate formation at low temperatures. The time-dependent water recovery shows a three-stage feature, including exponential growth, linear increase, and stable stages, owing to the interaction between the driving force of supercooling and the increasing K 3 PO 4 concentration during the reaction processes. The desalination efficiency shows an inverted volcanic shape with the increased concentration of feeding K 3 PO 4 solution. The pre-melting effect plays a critical role in improving desalination efficiency at high K 3 PO 4 concentrations. A maximum desalination efficiency of 85.0% was reached for treating an artificial solution with salinity as high as 42452 mg/L. Both desalted water and concentrated phosphorus-containing solution can be recovered by this method, which is attractive for producing freshwater with potential for recovery of resources. [Display omitted] • A method using cyclopentane hydrate formation was proposed to extract freshwater and enrich K 3 PO 4. • An impressive water recovery over 50% can be obtained in 2 h. • This method can treat an artificial solution with salinity as high as 42452 mg/L. [ABSTRACT FROM AUTHOR]

• High water recovery can be obtained via cyclopentane hydrate formation. • Halide ions have different capability in hindering hydrate formation. • High purity fresh water can be produced via multi-stage hydrate desalination. Hydrate-based desalination is an attractive and energy-effective method. In order to obtain high water recovery and purity, the desalination and Li+ enrichment performance were examined using single-stage desalination via graphite-promoted cyclopentane (CP) hydrate formation. LiCl, LiBr and LiI aqueous solutions with concentration ranging from 0.01 to 0.6 mol/L were used as brine. The rate for CP hydrate formation is determined by concentration, independent of the type of used salts. Halide ions were found to have the different capability in hindering CP hydrate-based desalination, with an order of Cl− < Br− < I−. The desalination efficiency was improved with increased concentration. Water recovery of 40% can be obtained in 1 h reaction, demonstrating the high efficiency of hydrate-based desalination. The desalination efficiency remains constant at around 70% over 24 h reaction, which can be dramatically enhanced by multi-stage desalination. The graphite powder, as the promoter for hydrate formation shows impressive recycling stability. The finding in this study would be of great help for developing effective desalination processes to produce fresh water and enrich high-value salts via CP hydrates. [ABSTRACT FROM AUTHOR]

The local reconfiguration of charge density achieved by Cu-O-Zn heterointerface derived from metal-organic frameworks, balances the CO 2 RR and HER processes, enabling efficient conversion from CO 2 to syngas with controllable CO/H 2 ratios. [Display omitted] • Cu-ZnO catalyst was successfully prepared by MOF-derived strategy. • MOF-derived porous carbon restricts the nanoscale size of bimetallic particles. • The porous carbon skeleton ensures the exposure of Cu-O-Zn interface sites. • Cu-O-Zn interface modulates the adsorption of the key intermediates. • The Cu-ZnO catalyst realize high CO selectivity and wide CO/H 2 ratios. Electrochemical reduction of CO 2 (CO 2 RR) to syngas is a promising approach for mitigating excessive CO 2 emissions and producing liquid fuels and industrial chemicals. However, achieving a suitable CO/H 2 ratio in a one-step reaction and a high current density remains a significant challenge. Herein, we prepare Cu-ZnO catalyst with Cu-O-Zn heterogeneous interface derived from metal-organic frameworks (MOFs) to catalyze the conversion of CO 2 to syngas. By constructing a Cu-O-Zn heterointerface, the bimetallic electronic configurations are modulated, wherein the reconfiguration of electron density induced by electron delocalization enhances the stabilization of *COOH intermediate and the production of CO. Moreover, the porous carbon derived from MOFs restricts the nanoscale size of bimetallic particles, ensuring abundant Cu-O-Zn heterointerface and exposed active sites, while preventing nanoparticle detachment and aggregation during the reaction process. The obtained catalysts realize high CO selectivity (75.6% of CO Faradaic efficiency) and wide CO/H 2 ratio (0.38–3.22) within a relatively narrow potential window and demonstrating excellent stability. This study offers insights into the rational design of high-performance multiphase electrocatalysts. [ABSTRACT FROM AUTHOR]

Gas hydrate-based CO 2 storage, using only water cages, provides an environmentally friendly and energy-efficient solution to reduce greenhouse gas emissions. However, the sluggish formation kinetics of gas hydrate is hindered by the limited reaction interfaces, thereby impeding the practical utilization of hydrate-based greenhouse gas storage. Herein, we reported a novel strategy to fabricate natural vermiculite and tannic acid composite aerogels as the effective substrates for boosting CO 2 hydrate formation. The results show that the formation kinetics of CO 2 hydrate in the aerogels exhibits composition dependence and an outstanding CO 2 storage capacity of 130.1 v/v (corresponding to 0.114 mol CO 2 /mol water). Inverse gas chromatography was used to analyze the surface energy and its components of the aerogels. Raman spectra and nuclear magnetic resonance were used to unravel the water molecule assembly and states. The CO 2 uptake capacity can be further improved by compressing the aerogel to 75 % of the original volume, showing an impressive storage capacity of 146.8 v/v. The as-made aerogels demonstrated outstanding cycle stability and short induction time for CO 2 hydrate formation. The results of this study pave the way for designing effective CO 2 hydrate promoters and facilitating promising CO 2 capture and storage technologies via gas hydrate. [Display omitted] • Monolithic aerogel can be easily fabricated by cross-linking vermiculite nanosheets. • The surface compositions and pore structures of aerogels can be finely tuned. • Aerogels have excellent CO 2 storing capacity by boosting hydrate formation. • Hydrogen bond arrangement plays the most vital role in hydrate formation. [ABSTRACT FROM AUTHOR]

Natural gas hydrates are a potential future energy modality with the advantages of clean burning and large resource reserves and have attracted worldwide attention. Natural gas hydrates formation and dissociation impact the skeletal structure and mechanical properties of porous media sediments. In addition, there is a synergistic effect between the migration of fine clay particles in porous media and hydrate behavior. In this study, methane hydrate was examined in-situ using a low-field nuclear magnetic resonance system in the presence of two suspensions of clay particles with different stability. The results showed that clay particles impacted methane hydrate formation and dissociation and the pore structure of porous media. Hydrate nucleated preferentially in large pores, causing them to split into smaller pores; the presence of clay particles, especially illite, improved the water conversion rate. The results indicated that water content in large pores increased after hydrate dissociation but was discontinuous among different pores. When illite was present, the distribution was more continuous; when montmorillonite was present, the water distribution of the large pores was similar to that of the original state. This work increases our understanding of the kinetics, water migration, and pore structure alteration of methane hydrate formation and dissociation in sediments with clay particles and provides support for the safe and efficient development of natural gas hydrates. • Clay particles impacted methane hydrate formation and dissociation • Hydrate nucleated preferentially in large pores • Clay particles, especially illite, improved the water conversion rate • Water content in large pores increased after hydrate dissociation but was discontinuous among different pores [ABSTRACT FROM AUTHOR]