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Developing efficient and low-cost electrocatalysts for oxygen evolution reaction is crucial in realizing practical energy systems for sustainable fuel production and energy storage from renewable energy sources. However, the inherent linear scaling relation for most catalytic materials imposes a theoretical overpotential ceiling, limiting the development of efficient electrocatalysts. Herein, using modeled Na x Mn 3 O 7 materials, we report an effective strategy to construct better oxygen evolution electrocatalyst through tuning both lattice oxygen reactivity and scaling relation via alkali metal ion mediation. Specifically, the number of Na + is linked with lattice oxygen reactivity, which is determined by the number of oxygen hole in oxygen lone-pair states formed by native Mn vacancies, governing the barrier symmetry between O–H bond cleavage and O–O bond formation. On the other hand, the presence of Na + could have specific noncovalent interaction with pendant oxygen in *OOH to overcome the limitation from linear scaling relation, reducing the overpotential ceiling. Combining in situ spectroscopy-based characterization with first-principles calculations, we demonstrate that an intermediate level of Na + mediation (NaMn 3 O 7 ) exhibits the optimum oxygen evolution activity. This work provides a new rational recipe to develop highly efficient catalyst towards water oxidation or other oxidative reactions through tuning lattice oxygen reactivity and scaling relation. While water-splitting provides a renewable means to generate fuel, the water-oxidation half-reaction is considered a bottleneck process. Here, authors tune lattice oxygen reactivity and scaling relations via alkali metal ion mediation in NaMn 3 O 7 for oxygen evolution electrocatalysis.

The excessive dependence on fossil fuels contributes to the majority of CO2 emissions, influencing on the climate change. One promising alternative to fossil fuels is green hydrogen, which can be produced through water electrolysis from renewable electricity. However, the variety and complexity of hydrogen evolution electrocatalysts currently studied increases the difficulty in the integration of catalytic theory, catalyst design and preparation, and characterization methods. Herein, this review first highlights design principles for hydrogen evolution reaction (HER) electrocatalysts, presenting the thermodynamics, kinetics, and related electronic and structural descriptors for HER. Second, the reasonable design, preparation, mechanistic understanding, and performance enhancement of electrocatalysts are deeply discussed based on intrinsic and extrinsic effects. Third, recent advancements in the electrocatalytic water splitting technology are further discussed briefly. Finally, the challenges and perspectives of the development of highly efficient hydrogen evolution electrocatalysts for water splitting are proposed. This review presents varieties of representative hydrogen evolution reaction (HER) electrocatalysts benefited from intrinsic and extrinsic design strategies and gives insight into classical/novel descriptors and reaction mechanism to provide the audience with a broad and basic understanding. Moreover, the progress on water‐splitting technology is also discussed. Some invigorating perspectives on the challenges and future directions at the HER field are provided.

The conversion of biomass is a favorable alternative to the fossil energy route to solve the energy crisis and environmental pollution. As one of the most versatile platform compounds, 5‐hydroxymethylfural (HMF) can be transformed to various value‐added chemicals via electrolysis combining with renewable energy. Here, the recent advances in electrochemical oxidation of HMF, from reaction mechanism to reactor design are reviewed. First, the reaction mechanism and pathway are summarized systematically. Second, the parameters easy to be ignored are emphasized and discussed. Then, the electrocatalysts are reviewed comprehensively for different products and the reactors are introduced. Finally, future efforts on exploring reaction mechanism, electrocatalysts, and reactor are prospected. This review provides a deeper understanding of mechanism for electrochemical oxidation of HMF, the design of electrocatalyst and reactor, which is expected to promote the economical and efficient electrochemical conversion of biomass for industrial applications. This review provides a deeper understanding of mechanism for electrochemical oxidation of 5‐hydroxymethylfurfural (HMF), the design of electrocatalyst and reactor, and points out the possible important development orientation, which is expected to promote the economical and efficient electrochemical conversion of biomass for industrial applications.

Rechargeable potassium-ion batteries have been gaining traction as not only promising low-cost alternatives to lithium-ion technology, but also as high-voltage energy storage systems. However, their development and sustainability are plagued by the lack of suitable electrode materials capable of allowing the reversible insertion of the large potassium ions. Here, exploration of the database for potassium-based materials has led us to discover potassium ion conducting layered honeycomb frameworks. They show the capability of reversible insertion of potassium ions at high voltages (~4 V for K 2 Ni 2 TeO 6 ) in stable ionic liquids based on potassium bis(trifluorosulfonyl) imide, and exhibit remarkable ionic conductivities e.g. ~0.01 mS cm −1 at 298 K and ~40 mS cm –1 at 573 K for K 2 Mg 2 TeO 6 . In addition to enlisting fast potassium ion conductors that can be utilised as solid electrolytes, these layered honeycomb frameworks deliver the highest voltages amongst layered cathodes, becoming prime candidates for the advancement of high-energy density potassium-ion batteries. The development of potassium-ion batteries requires cathode materials that can maintain the structural stability during cycling. Here the authors have developed honeycomb-layered tellurates K 2 M 2 TeO 6 that afford high ionic conductivity and reversible intercalation of large K ions at high voltages.

Because of the global trends of energy demand increase and decarbonization, developing green energy sources and increasing energy conversion efficiency are recently two of the most urgent topics in energy fields. The requirements for power level and performance of converter systems are continuously growing for the fast development of modern technologies such as the Internet of things (IoT) and Industry 4.0. In this regard, power switching devices based on wide-bandgap (WBG) materials such as silicon carbide (SiC) and gallium nitride (GaN) are fast maturing and expected to greatly benefit power converters with complex switching schemes. In low- and medium-voltage applications, GaN-based high-electron-mobility transistors (HEMTs) are superior to conventional silicon (Si)-based devices in terms of switching frequency, power rating, thermal capability, and efficiency, which are crucial factors to enhance the performance of advanced power converters. Previously published review papers on GaN HEMT technology mainly focused on fabrication, device characteristics, and general applications. To realize the future development trend and potential of applying GaN technology in various converter designs, this paper reviews a total of 162 research papers focusing on GaN HEMT applications in mid- to high-power (over 500 W) converters. Different types of converters including direct current (DC)–DC, alternating current (AC)–DC, and DC–AC conversions with various configurations, switching frequencies, power densities, and system efficiencies are reviewed.

The oxygen evolution reaction (OER) is a key process in electrochemical energy conversion devices. Understanding the origins of the lattice oxygen oxidation mechanism is crucial because OER catalysts operating via this mechanism could bypass certain limitations associated with those operating by the conventional adsorbate evolution mechanism. Transition metal oxyhydroxides are often considered to be the real catalytic species in a variety of OER catalysts and their low-dimensional layered structures readily allow direct formation of the O–O bond. Here, we incorporate catalytically inactive Zn 2+ into CoOOH and suggest that the OER mechanism is dependent on the amount of Zn 2+ in the catalyst. The inclusion of the Zn 2+ ions gives rise to oxygen non-bonding states with different local configurations that depend on the quantity of Zn 2+ . We propose that the OER proceeds via the lattice oxygen oxidation mechanism pathway on the metal oxyhydroxides only if two neighbouring oxidized oxygens can hybridize their oxygen holes without sacrificing metal–oxygen hybridization significantly, finding that Zn 0.2 Co 0.8 OOH has the optimum activity. Oxygen evolution is one half of the overall water splitting reaction to produce hydrogen. Although this reaction is well studied, there remains debate over the particulars of the catalytic mechanism. Here, the authors investigate Co–Zn oxyhydroxide electrocatalysts, and suggest that the mechanism depends on the amount of Zn 2+ they contain.

The spin degree of freedom is an important and intrinsic parameter in boosting carrier dynamics and surface reaction kinetics of photocatalysis. Here we show that chiral structure in ZnO can induce spin selectivity effect to promote photocatalytic performance. The ZnO crystals synthesized using chiral methionine molecules as symmetry-breaking agents show hierarchical chirality. Magnetic circular dichroism spectroscopic and magnetic conductive-probe atomic force microscopic measurements demonstrate that chiral structure acts as spin filters and induces spin polarization in photoinduced carriers. The polarized carriers not only possess the prolonged carrier lifetime, but also increase the triplet species instead of singlet byproducts during reaction. Accordingly, the left- and right-hand chiral ZnO exhibit 2.0- and 1.9-times higher activity in photocatalytic O 2 production and 2.5- and 2.0-times higher activities in contaminant photodegradation, respectively, compared with achiral ZnO. This work provides a feasible strategy to manipulate the spin properties in metal oxides for electron spin-related redox catalysis. The spin degree of freedom is a key intrinsic parameter for carrier dynamics and surface reaction kinetics in photocatalysis. Here, the authors report a chiral zinc oxide with spin selectivity effect. It can effectively induce spin polarization, thereby promoting electron spin-related redox catalysis.

Conventional therapies for pancreatic cancer involve limitations. Targeted therapy and immunotherapy are partially effective; however, they often cause adverse reactions and toxic side effects, sometimes necessitating treatment discontinuation. Early identification, diagnosis, and management of these treatment-related complications are crucial for ensuring patient safety while maintaining optimal therapeutic efficacy. This narrative review summarizes common adverse reactions to targeted therapy and immunotherapy for pancreatic cancer as well as corresponding management strategies.

Surface reconstruction generates real active species in electrochemical conditions; rational regulating reconstruction in a targeted manner is the key for constructing highly active catalyst. Herein, we use the high-valence Mo modulated orthorhombic Pr 3 Ir 1− x Mo x O 7 as model to activate lattice oxygen and cations, achieving directional and accelerated surface reconstruction to produce self-terminated Ir‒O bri ‒Mo (O bri represents the bridge oxygen) active species that is highly active for acidic water oxidation. The doped Mo not only contributes to accelerated surface reconstruction due to optimized Ir‒O covalency and more prone dissolution of Pr, but also affords the improved durability resulted from Mo-buffered charge compensation, thereby preventing fierce Ir dissolution and excessive lattice oxygen loss. As such, Ir‒O bri ‒Mo species could be directionally generated, in which the strong Brønsted acidity of O bri induced by remaining Mo assists with the facilitated deprotonation of oxo intermediates, following bridging-oxygen-assisted deprotonation pathway. Consequently, the optimal catalyst exhibits the best activity with an overpotential of 259 mV to reach 10 mA cm geo −2 , 50 mV lower than undoped counterpart, and shows improved stability for over 200 h. This work provides a strategy of directional surface reconstruction to constructing strong Brønsted acid sites in IrO x species, demonstrating the perspective of targeted electrocatalyst fabrication under in situ realistic reaction conditions. Regulating surface reconstruction is an important way to construct highly active catalyst for acidic water oxidation. Here the authors report high-valence Mo accelerates surface reconstruction of orthorhombic Pr3Ir1−xMoxO7 by activating lattice oxygen and cations, forming highly active and self-terminated Ir‒Obri‒Mo species with strong Brønsted acidity for acidic oxygen evolution reaction.

High-performance n-type organic electrochemical transistors (OECTs) are essential for logic circuits and sensors. However, the performances of n-type OECTs lag far behind that of p-type ones. Conventional wisdom posits that the LUMO energy level dictates the n-type performance. Herein, we show that engineering the doped state is more critical for n-type OECT polymers. By balancing more charges to the donor moiety, we could effectively switch a p-type polymer to high-performance n-type material. Based on this concept, the polymer, P(gTDPP2FT), exhibits a record high n-type OECT performance with μC * of 54.8 F cm −1 V −1 s −1 , mobility of 0.35 cm 2 V −1 s −1 , and response speed of τ on / τ off  = 1.75/0.15 ms. Calculations and comparison studies show that the conversion is primarily due to the more uniform charges, stabilized negative polaron, enhanced conformation, and backbone planarity at negatively charged states. Our work highlights the critical role of understanding and engineering polymers’ doped states. Conventional strategies to obtain n-type organic electrochemical transistors are based on lowering the lowest unoccupied molecular orbital. Here Lei et al., engineer the polymer doped states to fabricate high-performance n-type organic electrochemical transistors.