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Constructing artificial solid electrolyte interface on the Zn anode surface is recognized as an appealing method to inhibit zinc dendrites and side reactions, whereas the current techniques are complex and time‐consuming. Here, a robust and zincophilic zinc tungstate (ZnWO4) layer has been in situ constructed on the Zn anode surface (denoted as ZWO@Zn) by an ultrafast chemical solution reaction. Comprehensive characterizations and theoretical calculations demonstrate that the ZWO layer can effectively modulate the interfacial electric field distribution and promote the Zn2+ uniform diffusion, thus facilitating the uniform Zn2+ nucleation and suppressing zinc dendrites. Besides, ZWO layer can prevent direct contact between the Zn/water and increase the hydrogen evolution reaction overpotential to eliminate side reactions. Consequently, the in situ constructed ZWO layer facilitates remarkable reversibility in the ZWO@Zn||Ti battery, achieving an impressive Coulombic efficiency of 99.36 % under 1.0 mA cm−2, unprecedented cycling lifespan exceeding 1800 h under 1.0 mA cm−2 in ZWO@Zn||ZWO@Zn battery, and a steady and reliable operation of the overall ZWO@Zn||VS2 battery. The work provides a simple, low cost, and ultrafast pathway to crafting protective layers for driving advancements in aqueous zinc‐metal batteries. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) are highly promising for grid‐scale energy storage due to their high‐safety and low‐cost characteristics. Nevertheless, the progress in AZIBs has been impeded due to challenges encompassing corrosion, hydrogen evolution reaction, and the formation of dendrites on Zn anodes. These issues arise from the decomposition of active water molecules in the Zn2+ solvation structure in the electrolyte. Various strategies have been proposed to regulate the electrode/electrolyte interface to effectively address these problems. In spite of remarkable headway, an inadequacy of comprehensive studies addressing the mechanisms and evolutionary dynamics of the electrode/electrolyte interface is evident within scientific literature. This overview aims to provide a comprehensive overview of the strategies for regulating the electrode/electrolyte interface, focusing on dendrite‐free and side reactions‐suppressed AZIBs. These strategies include the introduction of metal ion additives, inorganic additives, surfactant additives, polymer additives and organic additives. Furthermore, a detailed examination is made on the effects and underlying mechanisms associated with modifying the electrolyte at the interface between the electrode and electrolyte. Moreover, an appraisal is provided on the performance metrics of diverse strategies and prospective research directions are recommended as well. [ABSTRACT FROM AUTHOR]

The dendrite issues associated with zinc anode lead to safety hazards and sluggish reaction kinetics, and largely restrain widespread application of aqueous zinc ion batteries (ZIBs). Herein, a functional separator composed of cellulose nanofibers and graphene oxide (CG) is developed for dendrite‐free and exceptionally stable ZIBs, realized by uniform hexagonal zinc deposits with manipulated crystallographic orientation (002) plane. This CG separator with negative surface charges and abundant zincophilic‐O groups ensures the strong interaction between the separator and zinc species, simultaneously inducing Zn(002) deposition due to the low mismatch between (002)Zn and (002)GO, thus initiating the preferential orientation of the zinc growth along the horizontal direction due to strong Zn binding ability, and uniform interfacial charge of Zn(002) deposition. Furthermore, the CG separator can effectively promote the uniform nucleation of Zn2+ and eliminate side effects. Accordingly, extremely low polarization of 58 mV at 0.5 mA cm−2, and ultralong cycle life over 1750 h at 2 mA cm−2 and 400 h at 20 mA cm−2 are achieved for the zinc anode. Notably, the CG separator significantly boosts rate capability and cyclability of coin‐type full batteries (Zn||Zn(CF3SO3)2||V2O5, Zn||ZnSO4+MnSO4||MnO2/graphite) and a flexible soft‐packaged battery (Zn||MnO2). Therefore, this work introduces a sustainability consideration in to the design of separators for constructing dendrite‐free ZIBs. [ABSTRACT FROM AUTHOR]

Water electrolysis is considered as the most favorable method to generate hydrogen because of its environmentally friendly approach. As an upgradation of this process, the introduction of urea gives improved energy conversion efficiency and can also be used for the treatment of urea-rich wastewater. Inspired by the above, a bifunctional electrocatalyst, namely NiCuP@NiCu supported on graphitic carbon, is prepared for the first time via high-temperature pyrolysis and in-situ phosphidization process. The carbon support endorses better electron transference, and the presence of mixed active metal redox couples (Mx+/My+, M = Ni&Cu) and their M-O/O–C bonds formation with urea molecule collectively leads to substantial UOR activity. Under alkaline conditions with 0.33 M urea in 1.0 M KOH, the NiCuP@NiCu/C drives 10 mA cm−2 current density with a minimum potential of 1.242 V and overpotential of 98 mV for urea oxidation reaction (UOR) and hydrogen evolution reaction (HER), respectively. What is significant is that NiCuP@NiCu/C is explored as a bifunctional electrocatalyst to construct two electrode electrolyzer, which only requires the minimum potential of 1.313 V to drive 10 mA cm−2 current density. Furthermore, the NiCuP@NiCu/C equipped electrolyzer is used under human urine sample and achieved the maximum H 2 production of 0.387 mmol. From the aforementioned outcomes, this works delivers a facile method for exploring an efficient bifunctional electrocatalyst for urea electrolysis and providing a new path to real-time fuel approach enabled H 2 production. • Baby diapers inspired NiCuP@NiCu/C is developed with two-step strategy. • Bifunctional activity favours to urea oxidation and hydrogen evolution reactions. • Metal redox couple involves to produces hydrogen from urea and human urine. [ABSTRACT FROM AUTHOR]

Developing efficient, economic, and environment-friendly electrocatalysts to meet the industrialized hydrogen evolution reaction (HER) needs is highly desired for dealing with the energy crisis. Under the known premise, how to reasonably control the doping amount of copper greatly influences the structure and is one of the key factors affecting the performance of the catalyst. Herein, a series of Ni–Cu–C electrocatalysts are successfully synthesized through a simple electrodeposition method. The unique dendritic morphology can be obtained by adjusting the different glucose concentrations. DFT simulation reveals that the proper proportion of copper can significantly modulate the H adsorption-free energy Δ G H ∗ It can boost the intrinsic activity of Ni–Cu–C catalysts. NCC-3 delivers an overpotential of 87 mV and 165 mV in alkaline media at the current density of 10 mA cm−2 and 100 mA cm−2, respectively and presents outstanding long-term stability for 50 h. Such excellent HER activity stems from a large ECSA area and better electron-transfer ability. The study presents a feasible way to control metal alloy catalysts' composition in the electrodeposition process. • Ni–Cu–C catalyst with lower overpotential (η 10mA cm −2 = 87 mV) and long-time stability (50 h) was synthesized successfully. • The doping ratio of the Ni–Cu can be controlled by the concentration of glucose in the electrodeposition process. • The Ni–Cu–C catalyst has a unique dendritic morphology with large ECSA area of 210 cm2. • DFT simulation verified that the reasonable doping of copper can moderated H adsorption free energy. [ABSTRACT FROM AUTHOR]

Hydrogen technology is widely considered a novel clean energy source, and electrolysis is an effective method for hydrogen evolution. Therefore, efficient hydrogen evolution reaction (HER) catalysts are urgently needed to replace precious metal catalysts and meet ecological and environmental protection standards. Herein, Ni–Mn–P electrocatalysts are synthesized using facile electrodeposition technology. The influence of the Mn addition on the catalytic behavior is studied by the comprehensive analysis of catalytic performance and morphology of the catalysts. Among them, the Ni–Mn–P0.01 catalyst exhibits small coral-like structures, greatly improving the adsorption and desorption of hydrogen ions and reducing the overpotential hydrogen evolution. Consequently, overpotential at 10 mA cm−2 electric current density is 113 mV, and the value of the Tafel slope achieves 74 mV/dec. Furthermore, the Ni–Mn–P catalyst shows long-time (20 h) stability at current densities of 10 and 60 mA/cm2. The results confirm that the synergistic effect of Ni, Mn, and P accelerates the electrochemical reaction. Meanwhile, the addition of manganese element can change the micromorphology of the catalyst, thereby exposing more active sites to participate in the reaction, enhancing water ionization, improving the catalytic performance. This study opens a new way toward improving the activity of the catalyst by adjusting Mn concentration during the electrodeposition process. [Display omitted] • Ni–Mn–P electrocatalysts are synthesized by facile electrodeposition technology. • 3D spherical microstructure Ni–Mn–P catalyst can be formed. • 3D spherical microstructure improves the adsorption and desorption of hydrogen ions. • Ni–Mn–P catalyst improves the hydrogen evolution reaction and longtime stability. [ABSTRACT FROM AUTHOR]

Synthesis of graphitic carbon nitride (g-C 3 N 4) is a simple, fast, metal-free, cost-effective with potential photocatalytic hydrogen evolution activity in solving energy crisis and environmental pollution. However, the low separation efficiency of electron-hole pairs of pure g-C 3 N 4 is still limited the real applications. In this work, we synthesized a g-C 3 N 4 photocatalyst with hollow porous worm-like structure morphology as well as phosphorus (P) doping through simple thermal polymerization with NaH 2 PO 4 ·2H 2 O as both P source and template. The results show that the synthesized g-C 3 N 4 photocatalysts with hollow porous worm-like structure. The specific surface area of modified photocatalysts can be enlarged from 39.29 m2/g to 51.36 m2/g, and the photochemical test show that the as-prepared photocatalysts has better visible light response and more highly separation efficiency of photogeneration electron-hole than that of pristine g-C 3 N 4. As expected, the photocatalytic hydrogen measurements reveal that the obtained P-doped hollow porous worm-like structured g-C 3 N 4 has highly efficient activity than pure g-C 3 N 4 under visible light irradiation. The photocatalytic hydrogen production capacity can reach up to 10.985 mmol/g for 5 h, which is about 7.6 times that of the pure g-C 3 N 4. Finally, based on the above analysis, we further proposed a reasonable photocatalytic mechanism. This work provides an idea for synthesis of an efficient g-C 3 N 4 based photocatalysts. [Display omitted] • The hollow structured P-doped g-C 3 N 4 photocatalysts were successfully synthesized. •Simple thermal polymerization with NaH 2 PO 4 ·2H 2 O as both P source and template was applied. •The band gap of photocatalysts with intruding phosphorus is narrowed slightly. •The obtained catalysts exhibit high H2 generation activity in both DI and sea water. [ABSTRACT FROM AUTHOR]

[Display omitted] • We reasonably designed a series of TM@WS 2 candidates for NRR electrocatalysts. • Cr@WS 2 , Tc@WS 2 and Os@WS 2 are the most promising catalysts for N 2 fixation. • The origin of NRR activity on TM@WS 2 was theoretically revealed. Developing the novel types of electrocatalysts with intrinsic stability, high activity and selectivity is a significant mission to advance the sustainable conversion of naturally abundant N 2 to NH 3 , but it remains a long-standing challenge. Herein, through theoretical screening approach, focusing on addressing this challenge, we rationally designed a series of WS 2 monolayer decorated by single transition metal (TM) atom as TM@WS 2 candidates and systematically explored their potentials for catalyzing N 2 reduction by building a full profile of stability, activity and selectivity. Our results unveil that, among 26 candidates, Cr@WS 2 , Tc@WS 2 and Os@WS 2 finally stand out as the most promising candidates, on which the adsorbed N 2 molecule can be efficiently converted into NH 3 through the distal mechanism with the limiting potentials of −0.37, −0.27 and −0.33 V, respectively, and impressively, the competing HER process can be pronouncedly inhibited. In particular, the activity trend is constructed by using *NNH adsorption energy and φ , and ICOHP reveals the origin of catalytic activity toward NRR. Our investigation not only contributes to the development of the highly efficient electrocatalysts, but also provides insightful views on the optimal design of WS 2 -based catalysts for advanced NH 3 synthesis. [ABSTRACT FROM AUTHOR]

• A systematic theoretical study of the OER electrocatalytic activity of MoS 2 /g -C 3 N 4 heterojunction was performed. • The theoretical overpotential of the MoS 2 /g-C 3 N 4 heterojunction was significantly reduced nearly 69% from 2.52 to 0.78 V compared with the pristine MoS 2. • The outstanding OER activity of the MoS 2 /g-C 3 N 4 heterojunction mainly originates from the electronic coupling between MoS 2 and g-C 3 N 4. Developing and designing highly efficient oxygen evolution reaction (OER) electrocatalysts is full of significance to achieve complete water splitting. In this work, using density functional theory (DFT) calculations, we performed a systematic theoretical study of the OER electrocatalytic activity of MoS 2 /g-C 3 N 4 heterojunction. We find that the construction of heterojunction can efficiently modify the electronic properties of MoS 2 phase, facilitate electron transfer, and thereby improving OER activity. In comparison to the pristine MoS 2 monolayer, the theoretical overpotential of the MoS 2 /g-C 3 N 4 heterojunction was significantly reduced nearly 69% from 2.52 to 0.78 V. Such outstanding OER activity mainly originates from the electronic coupling between MoS 2 and g-C 3 N 4. Overall, the present findings not only provide a vital insight into the catalytic mechanism of the enhanced OER activity of MoS 2 /g-C 3 N 4 heterojunction, but also provide a new pathway to develop high-performance OER electrocatalysts for future energy conversion applications. [ABSTRACT FROM AUTHOR]

Zinc-ion batteries (ZIBs) are promising energy storage system owing to the low cost and high safety features. As the most-used anode material, zinc metal always encounters poor coulombic efficiency (CE) and cycling stability, because of the serious zinc dendrite and harmful side reactions on Zn surface. Here, a solid-phase non-adhesive homogeneous Nano-Si layer has been embedded on the Zn surface (Zn-Si) via an ultra-facile grinding method. The Nano-Si layer can regulate an even electric field distribution to achieve a homogeneous zinc deposition, and it also can greatly lower the charge transfer resistance and nucleation energy barrier of Zn2+ to facilitate the zinc deposition, thus achieving a dendrites-free and long-life Zn anode. Encouragingly, the zinc symmetrical battery with Zn-Si anode delivers a superior CE of 99.6 % in 1000 cycles under 5 mA cm−2, and a stable cycle lifespan of 3600 h under 1 mA cm−2 with much lower polarization potential (42 mV), outperforming the symmetrical battery with pure Zn anode (455 h, 59 mV) and various previously reported strategies. Additionally, the effectiveness of Nano-Si layer is further proved in the Zn-Si/MnO 2 battery, which presents a greatly improved capacity retention and cycling performance. [Display omitted] • Zn-Si anode has been prepared via a facile grinding process with sandpaper and Nano-Si powder. • Zn-Si anode shows lower the charge transfer resistance and nucleation energy overpotential. • Zn-Si can prevent the formation of zinc dendrites and by-products. • Zn-Si anode can further improve the electrochemical performance of full battery. [ABSTRACT FROM AUTHOR]

• Cyano group and carbonyl group modified g-C 3 N 4 nanofragment were fabricated. • The modified g-C 3 N 4 shows porous and ultrathin fragment morphology. • Cyano group and carbonyl group efficiently separate charge carriers. • Defect assemblage in g-C 3 N 4 acts as active sites for photocatalytic reaction. • The modified g-C 3 N 4 yields a 10 times enhancement of H 2 compared with pure g-C 3 N 4. Poor light utilization and charge separation are the major factors that retard performance of g-C 3 N 4 and solar conversion application to green energy. Herein, with the aim to address these issues and enhance photocatalytic hydrogen performance, we design and synthesize the modified g-C 3 N 4 via defect assemblage of cyano group and carbonyl group. Cyano group and carbonyl group linked in the apex of heptazine unit were loaded into g-C 3 N 4 framework, endowing g-C 3 N 4 with extended light response range, tunable band structure and fast charge separation. By experiments analysis and theoretical calculations, the such a defect assemblage can attract photo-charge from other parts of heptazine unit and serve as active sites in photocatalytic process. Therefore, the modified g-C 3 N 4 material show a ten times higher photocatalytic hydrogen amount than the pristine one and the corresponding apparent quantum efficiency under 405 and 420 nm are 32.30 % and 17.94 %, respectively. In this work, the defect assemblage into g-C 3 N 4 shows the potential of synergistic effect of different defects on enhancing photocatalytic performance, which can pave a new avenue for the defect engineering in photocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • CN-CoO/CdS p-n type heterojunctions are formed using C, N co-doped Co 3 O 4 and CdS. • CN-CoO/CdS has higher visible light absorption, faster charge separation and excellent photoelectrochemical performance. • The outstanding photocatalytic performance of CN-CoO/CdS is mainly attributed to its built-in electric field. • The photocatalytic hydrogen evolution rate of the optimal 15%CN-CoO/CdS reaches 64.36 mmol·g−1·h−1 under visible light. • The 15%CN-CoO/CdS exhibits excellent stability during the photocatalytic cycle for hydrogen evolution reaction with 30 h. As one of the most effective strategies for the storage and utilization of solar energy, the development of photocatalytic technology has received extensive attention. The core work, the design and modification of photocatalysts, is very significance. Herein, we prepared C, N co-doped Co 3 O 4 (CN-CoO) by a simple method and composited it with CdS to form CN-CoO/CdS p-n type heterojunctions. The prepared materials are characterized by numerous tests, such as XRD, SEM, TEM, XPS, and photoelectrochemical measurement. Due to the excellent electrochemical performance of CN-CoO and the built-in electric field in CN-CoO/CdS, the efficient separation of photogenerated charges is realized. Compared with CdS (1.11 ns), the average carrier lifetimes of the 15%CN-CoO/CdS (1.63 ns) is prolonged, which enhances photocatalytic hydrogen evolution activity of the composite materials. The hydrogen evolution rate of the optimal 15%CN-CoO/CdS is 6.78-fold greater than that of pristine CdS, and is as high as 64.36 mmol·g−1·h−1. Meanwhile, the 15%CN-CoO/CdS exhibits outstanding chemical stability after cyclic hydrogen production experiment for 30 h, and its apparent quantum efficiency (AQE) reaches 27.47% under monochromatic light at 405 nm. In addition, the formation process and photocatalytic hydrogen evolution mechanism of the CN-CoO/CdS p-n type heterojunctions are analyzed and discussed. This work provides a new idea for the construction of efficient photocatalytic heterojunctions through the modification and combination of semiconductors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous and 3D flower-like NiW-0.6A was synthesized by electrodeposition method. • The overpotential of NiW-0.6A is 98 mV (10 mA cm−2). • NiW-0.6A shows strong stability for 100 h in 1 M KOH. • Enhanced HER performance by intrinsic catalytic activity and twin boundaries. The development of cost-effective electrocatalysts to produce high-purity hydrogen by electrochemical water splitting is critical to addressing resource and environmental problems. Theoretically, NiW materials are considered to be an excellent HER electrocatalyst. However, current NiW catalysts for HER are not satisfactory. Herein, the NiW solid solution with twin boundaries is successfully fabricated by facile electrodeposition on copper sheet. As compared with Ni, the NiW-0.6A catalyst shows enhanced HER activity in 1 M KOH with the overpotential of 98 mV at 10 mA/cm2. Besides, NiW-0.6A exhibits excellent stability for 100 h at 20 mA/cm2. The excellent HER performance of NiW-0.6A may be attributed to the intrinsic catalytic activity and the defective twin boundaries exposing many active sites. This work could provide feasible suggestions for the design of efficient and high-performance NiW electrocatalysts for HER process.. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoN-anchored CdS hollow nanosphere was successfully prepared via in-situ adsorption deposition followed by nitrogenization treatment. • CoN/CdS-HS shows the improved light absorption, lower interface resistance and fast charge separation. • CoN/CdS-HS possesses outstanding photocatalytic hydrogen activity and stability with the AQE of 23.53% at 405 nm, compared with pristine CdS. • CoN nanoparticle acts as an electron predator to capture photoelectrons and accelerate the separation of charge carriers. The photocatalytic water splitting to produce hydrogen is of great significance to solve the energy crisis, so the development and research of the visible-light-driven energy conversion have the priority in the progress of photocatalytic technology. Herein, we synthesized CdS with hollow sphere (CdS-HS) structure and combined it with CoN to form CoN/CdS-HS photocatalytic system. The particular hollow sphere structure and cocatalyst CoN in the CoN/CdS-HS system increase the utilization of visible light and promote the separation and transfer of photo-generated carriers for photocatalysts, which greatly improves photocatalytic performance of materials. The time‐resolved photoluminescence spectra shows that the carrier lifetime of 15%CoN/CdS-HS is 7.52 ns, which is much larger than that of CdS (4.26 ns). In addition, the hydrogen output of the optimized 15%CoN/CdS-HS is 4.57 times superior to that of pristine CdS-HS under the same conditions. The photocatalytic hydrogen evolution rate of 15%CoN/CdS-HS reaches 58.80 mmol/g . h under visible light with an apparent quantum efficiency (AQE) of 23.53% at 405 nm monochromatic light. After 25 h of photocatalytic reaction, the 15%CoN/CdS-HS can still maintain excellent overall stability. This work provides an idea for the design and development of efficient visible-light-driven photocatalysts in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-doped Ni catalysts can be successfully synthesized by electrodeposition. • The incorporation of Cu can improve the electrocatalytic performance of Ni. • Cu-doped Ni can optimize the hydrogen binding energy on catalyst surface. Bifunctional catalyst, as a feasible way to produce hydrogen, has been regarded as an effective issue for mitigation of the greenhouse effect, and thus has attracted extensive attention. Inspired by the traditional electrodeposition technology, we report a fast self-etching electrodeposition method to construct copper-incorporated three-dimensional Ni-Cu coated on copper sheets as a superior bifunctional catalyst. During the electrodeposition process, the copper substrate was corroded to form ammonium copper ions by ingenious design of the concentration of electrolyte, including ammonium chloride and sodium chloride. Meanwhile, we observe that the ratio of Ni to Cu could be changed via varying the current density. The optimized hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) overpotentials are 76 mV and 290 mV at 10 mA cm−2, respectively, which outperform the most reported bifunctional electrocatalysts until now. The calculation further demonstrates that the theoretical hydrogen desorption energy and OER overpotential of Ni-Cu are better than those of pure Ni and Cu. The prepared Ni-Cu electrocatalyst exhibits remarkable stability, especially in the HER reaction process stability test up to 50 h. The successful preparation of Ni-Cu electrocatalyst provides more possibility in the traditional electrodeposition synthesis of high performance electrocatalysts. [ABSTRACT FROM AUTHOR]

A noble-metal free and surface defect-induced mesoporous mixed valent NiO decorated TiO 2 heterostructure with tuned bandgap has been successfully prepared. Its outstanding visible-light driven hydrogen evolution and its excellent H 2 storage ability have been examined and confirmed. The formation of oxygen vacancies by surface defect creates the Ni3+ and Ti3+ on the interface of the heterostructure induce the efficient H 2 evolution, bench-marked by 1200% enhancement in catalytic performance. The underlying chemistries include the near-unity occupancy of e g orbital (t 2g 6 e g 1) of Ni3+ which speeds up the electron transfer and significantly promote the excellent electron-hole separation efficiency, establishes the outstanding overall charge-transfer efficiency and long-term photocatalytic activity in the visible light spectrum. Multiple Ti3+ adsorption centers in the structure attract multiple intact H 2 molecules per each center via a sigma - pi bonding motif - namely the Kubas interaction - which leads to 480% higher H 2 adsorption capability against the performance of the pristine mesoporous TiO 2. Not only the significant results, the study also provide an air-stable synthetic method on the basis of low-cost and abundant materials, which are strongly favoured for scaling up production. • Mesoporous (Ni2+/Ni3+)O @ TiO 2 is simply synthesized with targeted bandgap & defects. • For H 2 storage, about 480% enhancement is achieved via Kubas interaction mechanism. • For H 2 photosynthesis, 1200% improvement is achieved due to higher efficiency. [ABSTRACT FROM AUTHOR]