The membrane Electrode Assemblies (MEAs) electrolyzers are the most attractive systems for the electrolytic conversion of CO 2 into commodity chemicals and fuels at commercially relevant current densities. Suppressing the hydrogen evolution reaction (HER) is vital to the highly efficient electrochemical CO 2 reduction reaction (CO 2 RR). However, little attention has been paid to the HER. Herein, polybenzimidazole (PBI) Janus membranes with significant hydrophobic/hydrophilic asymmetric surface wettability were constructed for regulating the HER in CO 2 RR. The HER was modulated by adjusting the microstructure and surface hydrophobicity of the membrane as well as the CO 2 feeding method. The p-PBI-HCF MEA showed a significant suppression of HER and a 6-fold improvement in CO selectivity over p-PBI MEA. The p-PBI-HCF exhibited superior CO 2 RR performance in MEA compared to commercial membranes (FAA-3-50 and Nafion115). At 2.0 - 3.0 V, the CO Faraday efficiency (FE CO ) of the p-PBI-HCF MEA electrolyzer remained above 92%. The optimal energy efficiency range was between 2.0 and 2.4 V when the FE CO was close to 100%. The p-PBI-HCF provided 92% FE CO and a current density of 225 mA cm -2 at 3 V. This work provides guidelines for the development of viable PBI membranes and MEAs for CO 2 RR.

A hydrogen bond-dominated PBI/phenolic semi-interpenetrating network membrane with multiple-ion transport channels was developed, a novel membrane with 2 times higher hydroxide conductivity and excellent durability.

Adjustable ionic conductivity of γ-AlOOH-PBI membranes with arrayed AlOOH nanosheets inserting perpendicularly into the membrane surface was presented. The hydroxide ion conductivity of the novel membrane was about 3.1-fold higher than the pristine PBI membrane.

Abstract RBD-ACE2 interaction is critical in mediating SARS-CoV-2 attachment to its host cells. Blocking the attachment by inhibiting RBD-ACE2 binding is an effective way to prevent COVID-19 infection. In this study, we demonstrate that copper-ion exchanged zeolite (Cu-zeolite) binds specifically to RBD of SARS-CoV-2 via an unusual specific copper-content-dependent interaction of Cu-zeolite with RBD. Accordingly, Cu-zeolites prevent the virions from interacting with host cells, contributing to efficient and rapid SARS-CoV-2 neutralization. Therefore, Cu-zeolite has the potential to serve as a feasible and effective preventive measure to reduce exposure to the virus and as a therapeutic agent for post-exposure treatment of COVID-19.

The exploration of interfacial molecular interactions of protein-material integrations and how material modulate the protein structure and activity are essential to the safety evaluation of biomedical micro/nanomaterials, toxicity estimation and design of nano-drugs, and catalytic activity improvement of bio-inorganic functional hybrids. However, characterizing the interfacial molecular details of protein-micro/nanomaterial hybrids remains a great challenge. Herein, we introduce the protocol of lysine reactivity profiling-mass spectrometry (LRP-MS) strategy for probing the interfacial molecular structures between proteins and micro/nanomaterials. LRP-MS utilizes lysine residues as the endogenous probes to characterize the protein localization orientation, interaction sequence regions, binding sites, and modulated protein structures in the protein-material hybrids, which cannot be achieved by traditional spectroscopy methods. We describe the optimized heavy and light two-step isotope dimethyl labeling strategy for protein-material hybrids under their native and denaturing conditions in sequence. The comparative quantification results of lysine reactivity (referred as NLE) are only dependent on the native microenvironments of lysine local structures. We also highlight other critical steps including protein digestion, elution from materials, data processing, and interfacial structure analysis. The two-step isotope labeling steps need about 5 h, and the whole protocol including digestion, liquid chromatography-tandem mass spectrometry, data processing, and structure analysis needs about 3-5 days.

The fates of nanomaterials (NMs) in vivo are greatly dependent on their interactions with human serum proteins. However, the interfacial molecular details of NMs-serum proteins are still difficult to be probed. Herein, the molecular interaction details of human serum albumin (HSA) with Au and SiO2 nanoparticles have been systematically interrogated and compared by using lysine reactivity profiling mass spectrometry (LRP-MS). We demonstrated the biocompatibility of Au is better than SiO2 nanoparticles and the NMs surface charge state played a more important role than particle size in the combination of NMs-HSA at least in the range of 15–40 nm. Our results will contribute to the fundamental mechanism understanding of NMs-serum protein interactions as well as the NMs rational design.

The conversion of CO2 into good value fuel through CO2 reduction reaction (CO2RR) is promising to mitigate the energy crisis and greenhouse effect for a carbon-neutral economy. To this end, tremendous research and development have so far been devoted to the design of new high-performance electrocatalysts and electrochemical reactors. However, the impact of ion conductive membranes (ICMs) on conversion efficiency has received little attention. The final performance of CO2RR systems is strongly linked to the properties of ion conductive membranes in terms of ionic conductivity, selectivity, water absorption, and stability. However, numerous obstacles must be overcome in ICMs of CO2RR systems, including the balance of various properties of ICMs, the undesired crossover of products and reactants across the membrane, and the local acidic pH environment at the cathode. In this review, we highlight the importance and function of membranes and provide a first comprehensive analysis of the types of membranes reported for CO2RR systems. The compositions of various types of membranes were examined, and their advantages and disadvantages were compared. The mechanisms of ion transport in different membranes were then analyzed, and future challenges and prospects of ion conductive membranes in CO2RR were provided. This review aims to provide important guidance for the design of CO2RR membranes.

Semi-artificial photosynthesis interfacing catalytic protein machinery with synthetic photocatalysts exhibits great potential in solar-to-chemical energy conversion. However, characterizing and manipulating the molecular integration structure at the biotic-abiotic interface remain a challenging task. Herein, the biointerface molecular integration details of photosystem II (PSII)-semiconductor hybrids, including the PSII orientation, interfacial microdomains, and overall structure modulation, are systematically interrogated by lysine reactivity profiling mass spectrometry. We demonstrate the semiconductor surface biocompatibility is essential to the PSII self-assembly with uniform orientation and electroactive structure. Highly directional localization of PSII onto more hydrophilic Ru/SrTiO3:Rh surface exhibits less disturbance on PSII structure and electron transfer chain, beneficial to the high water splitting activity. Further, rational modification of hydrophobic Ru2S3/CdS surface with biocompatible protamine can improve the hybrid O2-evolving activity 83.3%. Our results provide the mechanistic understanding to the structure–activity relationship of PSII-semiconductor hybrids and contribute to their rational design in the future.

Perfluorooctanoic acid (PFOA) is a persistent environmental pollutant and will continually accumulate in blood due to its chemical inertness and strong interaction with serum proteins, especially serum albumin (SA), inducing highly adverse health risks. However, the molecular mechanisms of dynamic interactions between PFOA with serum proteins remain unclear, limiting the development of potential therapeutic strategies. Herein, we developed an integrated structural strategy to systematically profile the molecular details of dynamic interactions among PFOA, SA, and β-cyclodextrin (β-CD) by combing native mass spectrometry (nMS), lysine reactivity profiling (LRP), and molecular docking (MD) simulation. The SA site 1, site 2 pockets, and cleft nearby are observed as the primary interaction regions of PFOA. Further, β-CD can disrupt the PFOA combinations with bovine SA regions around sites Lys20, Lys280, Lys350, and Lys431-Lys439, with an overall reversing efficiency of about 26% at an identical concentration to PFOA. The interactome of PFOA with complex human serum proteins is globally profiled with molecular interaction details, including human serum albumin, apolipoprotein A-I, alpha-2-macroglobulin, and complement C3. Our results reveal molecular insights into the detail of the interaction between PFOA and serum proteins, beneficial to understanding PFOA toxicology.

Zymogen (prothrombin) activation is central to the process of haemostasis (blood clotting) in the body, preventing serious blood loss and death from haemorrhagic shock. Zeolites comprise a family of crystalline microporous aluminosilicates that show increasing promise for use in massive bleeding control. However, the mechanism of zeolite-initiated haemostasis has remained unclear. Here, we investigate zeolite-initiated thrombin activation at the molecular level, and show that a prothrombinase complex can assemble on the inorganic surface of calcium-ion-exchanged zeolites (Ca-zeolites). Compared to natural platelet-based physiological processes, prothrombin-to-thrombin conversion on the surface of Ca-zeolite displays a striking thrombin activation pattern, with an exceptionally high plateau thrombin activity and at least 12-fold enhanced endogenous thrombin. The results provide a mechanistic understanding of how the zeolite surface functionally contributes to thrombin activation, paving the way towards the design of improved agents for bleeding management.

It is challenging to develop an in vitro catalytic system to conduct natural surface-confined enzymatic reactions in a stable, efficient, and spatially defined manner. Here, we report that an artificial catalyst, which composes of trypsin and a calcium ion exchanged zeolite Y (trypsin/CaY), is capable of conducting surface-confined thrombin generation, and then constructs an artificial shortcut for classic, natural and complex blood coagulation cascade. The Ca2+ within the microporous cages play a key role in trypsin/CaY hybrid through tuning the bio-inorganic interaction and spatial orientation of the protease, which allows trypsin/CaY to display greatly enhanced catalytic performance in coagulation process. The in vivo efficiency of the artificial coagulation shortcut is further confirmed in massive bleeding and hemophilia animal models. Rapid hemostasis is achieved by trypsin/CaY hybrid in a hemophilia A mice tail bleeding model, where natural clotting system fails in response to bleeding event due to factor VIII deficiency. In a rabbit lethal femoral artery injury model, the blood loss of the artificial catalyst is decreased by 4–7 fold when compared to state-of-art clay- or zeolite-based topical agents.

Probing the conformational and functional hotspot sites within aqueous native protein complexes is still a challenging task. Herein, a mass spectrometry (MS)-based two-step isotope labeling-lysine reactivity profiling (TILLRP) strategy is developed to quantify the reactivities of lysine residues and probe the molecular details of protein-protein interactions as well as evaluate the conformational interventions by small-molecule active compounds. The hotspot lysine sites that are crucial to the SARS-CoV-2 S1-ACE2 combination could be successfully probed, such as S1 Lys(417) and Lys(444). Significant alteration of the reactivities of lysine residues at the interaction interface of S1-RBD Lys(386)-Lys(462) was observed during the formation of complexes, which might be utilized as indicators for investigating the S1-ACE2 dynamic recognition and intervention at the molecular level in high throughput.

Coalescence of droplets containing nanoparticles has been paid much attention regarding fabrication of functional photonic crystal (PC) patterns. However, most studies focus on the coalescence of droplets containing the same nanoparticles. Currently, an active challenge comes from the coalescence of droplets containing different nanoparticles due to the spontaneous mutual diffusion of different nanoparticles between coalescing miscible droplets driven by the released Gibbs free energy. Such diffusion breaks the self-assembly of nanoparticles into promising PCs with dual photonic band gaps (PBGs). In this work, a viscosity gradient was induced in coalescing droplets containing different nanoparticles to control the diffusion of nanoparticles and impede the diffusion across the coalescing interface. Nanoparticles diffused along the viscosity gradient to droplet surfaces and self-assembled into a period structure which enhanced the interaction of nanoparticles and contributed to impeding the random diffusion between droplets. At the same time, the high viscosity at the coalescing interface slowed down the horizontal movement of nanoparticles further and consequently the diffusion of nanoparticles across the interface was impeded. By use of such controlled diffusion of nanoparticles in the viscosity gradient, PCs with PBGs were achieved. These results demonstrate the controlled diffusion of nanoparticles during the coalescence of miscible droplets to facilely fabricate PCs with PBGs in the absence of an existing external field.

Two-dimensional (2D) MXenes have been extensively investigated for electrochemical energy storage because of their excellent electronic properties. In this work, a facile and effective method was developed to fabricate MXene/polypyrrole (MXene/PPy) composite film electrodes via one-step co-electrodeposition. In this process, 2D Ti3C2Tx-MXene nanosheets acted as a core polymer because of the functional groups, such as -F, -OH, or -O, on their surface, and pyrrole monomer radical cations (Py center dot(+)) would gradually polymerize on the surface and layer space of the 2D MXene nanosheets to form three-dimensional (3D) carambola-like MXene/PPy composite films. The 3D structure composite facilitated electron transfer and ionic diffusion, so the MXene/PPy composite film electrodes exhibited an outstanding electrochemical performance with a high gravimetric capacitance of 416 F g(-1) at a current density of 0.5 A g(-1) in a three-electrode system. The as-fabricated symmetric supercapacitors of ITO-glasses coated with MXene/PPy composite films also exhibited a high specific capacitance (184 F g(-1) at a scan rate of 10 mV s(-1)), excellent reliability and good cycling stability (approximately 86.4% retention after 5000 cycles, at 5 A g(-1)). (C) 2019 Elsevier Ltd. All rights reserved.

Lignin is the second most abundant and low-cost natural polymer, but its high value-added utilization is still lack of effective and economic ways. In this paper, waste lignosulfonate (LS) was introduced to fabricate antifouling membrane surfaces via layer-by-layer self-assembly with polyethyleneimine (PEI). The LS/PEI multilayers were successfully deposited on the polysulfone (PSf) membrane, as demonstrated by ATR-FTIR, XPS, Zeta potential measurements, AFM, and SEM. Meanwhile, the effect of the number of bilayers was investigated in detail on the composition, morphologies, hydrophilicity, and antifouling performance of the membrane surface. As a result, with the bilayer numbers increase to 5, the PSf membrane shows smooth surface with small roughness, and its water contact angle reduces to 44.1°, indicating the improved hydrophilicity. Accordingly, the modified PSf membrane with 5 LS/PEI bilayers repels the adsorption of protein, resulting in good antifouling performance. This work provides a green, facile, and low-cost strategy to construct antifouling membrane surfaces.

In recent years, supercapacitors are attracting great attention as one kind of electrochemical energy storage device, which have a high power density, a high energy density, fast charging and discharging, and a long cycle life. As a solution processing method, printing technology is widely used to fabricate supercapacitors. Printable nanomaterials are critical to the fabrication of high-performance supercapacitors by printing technology. In this work, the advantages of printing technology are summarized. Moreover, various nanomaterials used to fabricate supercapacitors by printing technology are presented. Finally, the remaining challenges and broad research as well as application prospects in printing high-performance supercapacitors with nanomaterials are proposed.

Silver amine ion aqueous solution was used as the inkjet ink, and the polydimethylsiloxane (PDMS) added reducing agent was served as the printing substrate. An oil-water interface reaction was made to generate silver nanoparticle by inkjet printing. A mosaic silver layer with 15–20 μm thickness was obtained. Bendable circuits were fabricated by inkjet printing technology. This fabricating method will provide a promising avenue for applications in functional materials patterning, flexible optoelectronic device, and related fields.

Taking advantage of the electron-current ability to generate, stabilize, and manipulate skyrmions prompts the application of skyrmion multilayers in room-temperature spintronic devices. In this study, the robust high-density skyrmions are electromagnetically generated from Pt/Co/Ta multilayers using Lorentz transmission electron microscopy. The skyrmion density is tunable and can be significantly enhanced. Remarkably, these generated skyrmions after optimized manipulation sustain at zero field with both the in-plane current and perpendicular magnetic field being switched off. The skyrmion generation and manipulation method demonstrated in this study opens up an alternative way to engineer skyrmion-based devices. The results also provide key data for further theoretical study to discover the nature of the interaction between the electric current and different spin configurations.

Magnetic skyrmions, particular those without the support of external magnetic fields over a wide temperature region, are promising as alternative spintronic units to overcome the fundamental size limitation of conventional magnetic bits. In this study, we use in situ Lorentz microscope to directly demonstrate the generation and sustainability of robust biskyrmion lattice at zero magnetic field over a wide temperature range of 16-338 K in MnNiGa alloy. This procedure includes a simple field-cooling manipulation from 360 K (higher than Curie temperature TC ∼ 350 K), where topological transition easily occurs by adapting the short-range magnetic clusters under a certain magnetic field. The biskyrmion phase is favored upon cooling below TC. Once they are generated, the robust high-density biskyrmions persist even after removing the external magnetic field due to the topological protection and the increased energy barrier.

Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn–Co–Ge–In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10−6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.