The high viscosity and low fluidity of heavy crude oil hinder its sorption by conventional porous sorbents, so the efficient clean‐up of such heavy crude oil spills is challenging. Recently, Joule ...heating has been emerging as a new tool to reduce the viscosity of heavy crude oil dramatically. However, this direct‐contact heating approach presents a potential risk due to the high voltage applied. To develop a non‐contact recovery of viscous crude oil, here, a new approach for the fabrication of a series of ferrimagnetic sponges (FMSs) with hydrophobic porous channels is reported, whose surface can be remotely heated to 120 °C within 10 s under an alternating magnetic field (f = 274 kHz, H = 30 kA m−1). Compared with the solar‐driven superficial heating, the integral magnetic heating in FMSs can result in a higher internal temperature of the sponges because of the confinement of thermal transport in the porous channels, which contributes to a dramatic decrease in oil viscosity and a significant increase in oil flow into the pores of FMSs. Furthermore, FMSs assembled with a self‐priming pump can achieve continuous recovery of viscous crude oil (33.05 g h−1 cm−2) via remotely magnetic heating.
A ferrimagnetic sponge with the skeletons coated with poly(dimethylsiloxane) and iron oxide nanoparticles is developed to achieve continuous recovery of viscous crude oil. Under the exposure of an alternating magnetic field, the viscosity of the viscous oil around the sponge decreases sharply, thus accelerating its absorption.
Clayey silt reservoirs bearing natural gas hydrates (NGH) are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit. They are ...proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017. Based on the understanding of the first production test, the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment, numerical and experimental simulation, and onshore testing of the reservoirs. After that, it conducted the second offshore NGH production test in 1225 m deep Shenhu Area, South China Sea (also referred to as the second production test) from October 2019 to April 2020. During the second production test, a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met, including wellhead stability, directional drilling of a horizontal well, reservoir stimulation and sand control, and accurate depressurization. As a result, 30 days of continuous gas production was achieved, with a cumulative gas production of 86.14 ×104 m3. Thus, the average daily gas production is 2.87 ×104 m3, which is 5.57 times as much as that obtained in the first production test. Therefore, both the cumulative gas production and the daily gas production were highly improved compared to the first production test. As indicated by the monitoring results of the second production test, there was no anomaly in methane content in the seafloor, seawater, and atmosphere throughout the whole production test. This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs. The industrialization of hydrates consists of five stages in general, namely theoretical research and simulation experiments, exploratory production test, experimental production test, productive production test, and commercial production. The second production test serves as an important step from the exploratory production test to experimental production test.
Oil sorbents play a very important part in the remediation processes of oil spills. To enhance the oil‐sorption properties and simplify the oil‐recovery process, various advanced oil sorbents and ...oil‐collecting devices based on them have been proposed recently. Here, we firstly discuss the design considerations for the fabrication of oil sorbents and describe recently developed oil sorbents based on modification strategy. Then, recent advances regarding oil sorbents mainly based on carbon materials and swellable oleophilic polymers are also presented. Subsequently, some additional properties are emphasized, which are required by oil sorbents to cope with oil spills under extreme conditions or to facilitate the oil‐collection processes. Furthermore, some oil‐collection devices based on oil sorbents that have been developed recently are shown. Finally, an outlook and challenges for the next generation of oil‐spill‐remediation technology based on oil‐sorbents materials are given.
Hydrophobic and oleophilic sorbent materials are demonstrated as promising candidates for the cleanup of oil spills. An overview of the latest developments and advances in the fabrication of oil sorbents through modification strategy, carbon‐based oil sorbents, and polymer‐based oil sorbents, as well as some smart oil sorbents and oil‐collecting devices based on oil‐sorbent materials are presented.
The performance of single‐atom electrocatalysts usually suffers from attenuation due to high energy states, especially in harsh environments. Therefore, as high‐efficiency electrocatalysts for ...hydrogen reduction reaction (HER), supported metal nanoclusters (NCs) with maximum metal atom efficiency are promising, yet the genuine mechanism involving rational orbital modulation is still arguable. Herein, the conjugating effect between electron‐donor boron (B)‐tethering engineering and iridium (Ir) that facilitates the electron capture of Ir atoms is explored, achieving highly dispersive Ir‐NCs confined in N, B co‐doped defective carbon (Ir@NBD‐C). The Ir@NBD‐C catalyst achieves displays remarkable high activity for HER in a pH‐universal range, in particular, with an ultralow overpotential of 7 mV (10 mA cm−2), high mass activity of 652.2 A gIr−1, and turnover frequency (TOF) of 1.90 H2 S−1 (100 mV) in 1.0 m KOH, outperforming almost all state‐of‐the‐art HER electrocatalysts. Operando characterizations and theoretical calculations unveil that the outstanding catalytic activity can attribute to the optimal binding to hydrogen intermediate species (H*) derived from the tunable and favorable electronic structure of the Ir site through the tethering of B heteroatoms. Undoubtedly, this work brings new insight into the design of catalysts with high intrinsic activity and thermodynamic stability.
Synergistic tethering of electron‐donor (B)/acceptor (N) heteroatoms regulates the electronic structure of Ir nanoclusters, resulting in high catalytic activity and optimal adsorption energy of hydrogen intermediate (H*) in HER.
Unidirectional underwater gas bubble (UGB) transport on a surface is realized by buoyant force or wettability gradient force (Fwet‐grad) derived from a tailored geography. Unfortunately, intentional ...control of the UGB over transport speed, direction, and routes on horizontal planar surfaces is rarely explored. Herein reported is a light‐responsive slippery lubricant‐infused porous surface (SLIPS) composed of selective lubricants and super‐hydrophobic micropillar‐arrayed Fe3O4/polydimethylsiloxane film. Upon this SLIPS, the UGB can be horizontally actuated along arbitrary directions by remotely loading/discharging unilateral near‐infrared (NIR) stimuli. The underlying mechanism is that Fwet‐grad can be generated within 1 s in the presence of a NIR‐trigger due to the photothermal effect of Fe3O4. Once the NIR‐stimuli are discharged, Fwet‐grad vanishes to break the UGB on the SLIPS. Moreover, performed are systematic parameter studies to investigate the influence of bubble volume, lubricant rheology, and Fwet‐grad on the UGB steering performance. Fundamental physics renders the achievement of antibuoyancy manipulation of the UGBs on an inclined SLIPS. Significantly, steering UGBs by horizontal SLIPS to configurate diverse patterns, as well as facilitating light‐control‐light optical shutter, is deployed. Compared with the previous slippery surfaces, light‐responsive SLIPS is more competent for manipulating UGBs with controllable transport speed, direction, and routes independent of buoyancy or geography derivative force.
A light‐responsive slippery lubricant‐infused porous surface (SLIPS) is fabricated by facile laser scanning for underwater bubbles (UGBs) manipulation. Through tuning the irradiating site of NIR, the UGBs can be horizontally actuated to arbitrary directions with regard to a tunable wettability gradient force (Fwet‐grad). Significantly, the fundamental physics allow for steering UGBs anti‐buoyancy.
The atmospheric CO2 concentration continues a rapid increase to its current record high value of 416 ppm for the time being. It calls for advanced CO2 capture technologies. One of the attractive ...technologies is physical adsorption‐based separation, which shows easy regeneration and high cycle stability, and thus reduced energy penalties and cost. The extensive research on this topic is evidenced by the growing body of scientific and technical literature. The progress spans from the innovation of novel porous adsorbents to practical separation practices. Major CO2 capture materials include the most widely used industrially relevant porous carbons, zeolites, activated alumina, mesoporous silica, and the newly emerging metal‐organic frameworks (MOFs) and covalent‐organic framework (COFs). The key intrinsic properties such as pore structure, surface chemistry, preferable adsorption sites, and other structural features that would affect CO2 capture capacity, selectivity, and recyclability are first discussed. The industrial relevant variables such as particle size of adsorbents, the mechanical strength, adsorption heat management, and other technological advances are equally important, even more crucial when scaling up from bench and pilot‐scale to demonstration and commercial scale. Therefore, we aim to bring a full picture of the adsorption‐based CO2 separation technologies, from adsorbent design, intrinsic property evaluation to performance assessment not only under ideal equilibrium conditions but also in realistic pressure swing adsorption processes.
Divide and conquer: This Review discusses the recent advances in adsorption‐based CO2 separation technology, from porous materials synthesis, adsorbents’ intrinsic property evaluation to performance assessments not only in view of the ideal equilibrium conditions but also in critically practical perspective.
A stretchable and multiple‐force‐sensitive electronic fabric based on stretchable coaxial sensor electrodes is fabricated for artificial‐skin application. This electronic fabric, with only one kind ...of sensor unit, can simultaneously map and quantify the mechanical stresses induced by normal pressure, lateral strain, and flexion.
Oxidative dehydrogenation of propane to olefins is a promising alternative route to industrialized direct dehydrogenation, but encounters the difficulty in selectivity control for olefins because of ...the overoxidation reactions that produce a substantial amount of undesired CO2. Here we report edge‐hydroxylated boron nitride, a metal‐free catalyst, that efficiently catalyzed dehydrogenation of propane to propylene with superior selectivity (80.2 %) but with only negligible CO2 formation (0.5 %) at a given propane conversion of 20.6 %. Remarkable stability was evidenced by the operation of a 300 h test with steady conversion and product selectivity. The active BNO. site, generated dynamically through hydrogen ion of B−OH groups by molecular oxygen, triggered propane dehydrogenation by selectively breaking the C−H bond but simultaneously shut off the pathway of propylene overoxidation towards CO2.
Olefin generation without a metal: Edge‐hydroxylated boron nitride shows superior selectivity for the oxidative dehydrogenation of propane to propylene with only negligible CO2 formation. The dynamically generated active BNO. site triggers propane dehydrogenation by selectively breaking the C−H bond by concomitantly avoiding propylene oxidation to CO2.
Conversion of light alkanes into industrial chemical olefins
via
oxidative dehydrogenation (ODH) is a promising route because of favorable thermodynamic and kinetic characteristics, but encounters ...difficulties in selectivity control for olefins because of over-oxidation reactions that produce a substantial amount of undesired carbon oxides. Compared to widely-developed metal oxide-based catalysts, functionalized boron nitride has recently been shown as a competitive system in the ODH of light alkanes because of its more superior selectivity toward olefins as well as negligible formation of CO
2
. It is also characterized by high productivity to light olefins, remarkable catalyst stability, superior anti-oxidation ability, and excellent thermal conductivity. This feature article highlights the recent developments in applying boron nitride towards the ODH reaction of light alkanes. By correlating structural character with catalytic behavior, we expect to provide more insights into the catalytic nature of boron nitride-based materials in ODH reactions. Finally, we envisage perspective directions for boron-based ODH catalysts.
We highlight recent progress on a newly-developed catalyst system, boron nitride, for selective oxidative dehydrogenation of light alkanes.
Driven by the persisting poor understanding of the sluggish kinetics of the hydrogen evolution reaction (HER) on Pt in alkaline media, a direct correlation of the interfacial water structure and ...activity is still yet to be established. Herein, using Pt and Pt–Ni nanoparticles we first demonstrate a strong dependence of the proton donor structure on the HER activity and pH. The structure of the first layer changes from the proton acceptors to the donors with increasing pH. In the base, the reactivity of the interfacial water varied its structure, and the activation energies of water dissociation increased in the sequence: the dangling O−H bonds < the trihedrally coordinated water < the tetrahedrally coordinated water. Moreover, optimizing the adsorption of H and OH intermediates can re‐orientate the interfacial water molecules with their H atoms pointing towards the electrode surface, thereby enhancing the kinetics of HER. Our results clarified the dynamic role of the water structure at the electrode–electrolyte interface during HER and the design of highly efficient HER catalysts.
On nickel–platinum alloy nanoparticles under alkaline conditions, the reactivity of interfacial water varies with its structure and the order of water dissociation. The inclusion of nickel re‐orientates interfacial water molecules with their hydrogen atoms pointing towards the electrode surface, thereby enhancing the kinetics of the hydrogen evolution reaction (HER).
