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Metal–organic frameworks (MOFs) derived nanostructures receive immense research focus due to its high porosity, conductivity, and structural tailrolability features. In this work, porous Zeolitic Imidazole Framework‐67 (ZIF‐67) to synthesize cobalt phosphide/carbon composite (ZCoPC) that serves as a positive electrode is utilized. Furthermore, porous and conductive office paper derived carbon (OPC) are utilized as a negative electrode to make a hybrid system. The metalloid characteristics, high conductivity, and good porosity of ZCoPC material makes it a high‐performance battery like electrode. ZCoPC electrode achieves maximum specific capacity of 192.6 mAh g−1 at 1 A g−1 using 1 m potassium hydroxide (KOH) electrolyte. Furthermore, surface and diffusion charge participation investigation are also undergone for ZCoPC electrode that helps in determining the actual charge dynamics occurring in the electrode. In addition, a supercapattery device is assembled using ZCoPC as battery electrode and OPC as supercapacitor electrode. The as fabricated OPC//ZCoPC hybrid supercapattery device delivers extraordinary energy density of 31.6 Wh kg−1 with a power density of 700 W kg−1 and also a long cycle life of 92.3% even after 10,000 charge–discharge cycles. Hence, these outcomes demonstrate that the synergy of porous MOF derived metal phosphide and OPC electrodes are beneficial for supercapattery devices. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (gCN) has shown great potential in photocatalysis. Developing suitable cocatalysts is a critical way to enhance gCN's photocatalytic performance. In this paper cobalt–nickel bimetallic phosphide (CoNiP) was used as a cocatalyst to modify gCN. A gCN/CoNiP composite was successfully prepared by a simple hydrothermal method. XRD, XPS, SEM, UV-vis DRS, and PL characterization studies showed that a Schottky junction-like structure was constructed between gCN and CoNiP, which intensified the visible light response, enhanced the charge transfer rate and prohibited the recombination of photogenerated carriers, thus significantly improving gCN photocatalytic activity. Under simulated sunlight, the removal efficiency of methylene blue (10 mg L−1) was 97.8% by 120 min of irradiation, 44.6% higher than that of gCN. The quenching experiment showed that ˙O2−, ˙OH and h+ were the main active species. Based on the above points, the possible mechanism of photocatalysis was deduced. [ABSTRACT FROM AUTHOR]

In this paper, a novel Pt/CoP/C photo-electro synergistic catalyst was successfully synthesized by a hydrothermal method combined with phosphorus doping treatment. The addition of Vulcan XC-72R is in favor of effectively preventing agglomeration of active catalytic sites, resulting in more uniform and smaller Pt and CoP nanoparticles. The as-obtained Pt/CoP/C shows excellent photo-electro catalytic performance for the HER with simulated solar light irradiation. The optimal hydrogen production is 5384.18 mmol h−1 g−1, which is obviously higher than that of the commercial catalyst (20 wt% Pt/C: 4608.52 mmol h−1 g−1). The research results show that introducing cobalt phosphide into the Pt catalyst can improve the electrocatalytic activity and stability for the HER; in particular, the existence of Co3O4 in Pt/CoP/C leads to an efficient photo-electro catalysis under irradiation, which significantly improves the catalytic activity of Pt. The results above provide a novel strategy for the rational design of cost-effective Pt-based composites towards a fast HER. [ABSTRACT FROM AUTHOR]

A stable and highly active core‐shell heterostructure electrocatalyst is essential for catalyzing oxygen evolution reaction (OER). Here, a dual‐trimetallic core‐shell heterostructure OER electrocatalyst that consists of a NiFeWS2 inner core and an amorphous NiFeW(OH)z outer shell is designed and synthesized using in situ electrochemical tuning. The electrochemical measurements of different as‐synthesized catalysts with a similar mass loading suggest that the core‐shell Ni0.66Fe0.17W0.17S2@amorphous NiFeW(OH)z nanosheets exhibit the highest overall performance compared with that of other bimetallic reference catalysts for the OER. Additionally, the nanosheet arrays were in situ grown on hydrophilic‐treated carbon paper to fabricate an integrated three‐dimensional electrode that affords a current density of 10 mA cm−2 at a small overpotential of 182 mV and a low Tafel slope of 35 mV decade−1 in basic media. The Faradaic efficiency of core‐shell Ni0.66Fe0.17W0.17S2@amorphous NiFeW(OH)z is as high as 99.5% for OER. The scanning electron microscope, transmission electron microscope, and X‐ray photoelectron spectroscopy analyses confirm that this electrode has excellent stability in morphology and elementary composition after long‐term electrochemical measurements. Importantly, density functional theory calculations further indicate that the core‐shell heterojunction increased the conductivity of the catalyst, optimized the adsorption energy of the OER intermediates, and improved the OER activity. This study provides a universal strategy for designing more active core‐shell structure electrocatalysts based on the rule of coordinated regulation between electronic transport and active sites. [ABSTRACT FROM AUTHOR]

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In this paper, the structural characteristics and catalytic mechanism for hydrogen evolution of ammonia borane of non-metal (N, S) doped CoP catalysts were studied in detail by density functional theory (DFT) calculations. Specifically, we first investigated the structure of the cobalt phosphide catalyzed ammonia borane models. In addition, based on the most stable structures, the mechanism of the hydrogen evolution reaction of ammonia borane catalyzed by three catalysts was studied, and four feasible reaction paths for the hydrogen evolution reaction of ammonia borane catalyzed by three catalysts were discussed. By comparing the activation energies of the control steps of different reaction paths, the optimal reaction paths for the hydrogen evolution of ammonia borane catalyzed by three different catalysts were determined. The catalytic activities of the three catalysts for the hydrogen evolution of ammonia borane were compared. We found that the N-doped catalyst was beneficial to improve the catalytic activity of CoP for the catalytic hydrogen evolution of ammonia borane, while the catalytic activity of S-doped CoP for the catalytic hydrogen evolution of ammonia borane is relatively weak. These results reveal the relationship between the physical properties of CoP (and its non-metal-doped variants) and their catalytic activity. Finally, these findings can be used to explain the underlying mechanism reported in previous experimental studies from a microscopic perspective. [ABSTRACT FROM AUTHOR]

Summary: The cost of platinum group metal (PGM) catalysts is one of the major obstacles in commercializing proton exchange membrane water electrolyzers (PEMWEs). The non‐PGM substituents are often more financially beneficial but low in activity and durability in the acidic environment. In this study, cobalt phosphide catalysts, which are promising non‐PGM alternatives for the hydrogen evolution reaction (HER) and have enhanced durability and single‐cell performance, were fabricated directly on carbon paper using the pulse electrodeposition method. As the dissolution potential (reported as ‐x vs saturated calomel electrode) of the pulse electrodeposition shifted in the positive direction, the P/Co ratio of the Co‐P‐x catalysts increased because of severe Co dissolution. Among the catalysts, Co‐P‐0.6, Co‐P‐0.5, and Co‐P‐0.4 (where the number indicates the negative dissolution potential) were rapidly degraded in acid, whereas Co‐P‐0.3, Co‐P‐0.2, and Co‐P‐0.1 showed high stability because of the relative amounts of CoP and Co2P phases. The acid‐dissolved Co‐P‐0.3 catalyst showed the best half‐cell performance (an overpotential of 143.85 mV at 10 mA/cm2) and durability, and the P‐Co and Coδ+ surface states are critical for its performance. Single‐cell tests using the Co‐P‐0.3 cathode revealed its remarkable performance of 1.89 A/cm2 at 2.0 Vcell, indicating its promise as a non‐PGM cathode material for PEMWEs. [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) have attracted extensive interest to catalyze the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). However, the development of TMPs with high conductivity is a great challenge. Herein, we report hybrids of cobalt phosphide (CoP) and copper phosphide (CuP) strongly coupled with ZIF-67 derived carbon as bifunctional ORR/OER electrocatalysts (CoP/CuP@NC). The as-prepared CoP/CuP@NC catalysts exhibit delightful activity and stability toward the ORR (E1/2 = 0.86 V) and the OER (E10 = 1.61 V). Moreover, the assembled Zn-air battery exhibits a small charge-discharge voltage gap and excellent stability. These remarkable electrocatalytic capabilities stem from the combined impact of active CoP/CuP components and the structural framework derived from ZIF-derived materials. This work provides a meaningful strategy for constructing high-performance bifunctional electrocatalysts for commercial Zn-air batteries. [ABSTRACT FROM AUTHOR]

New heteroleptic dppe appended Co(III)-dithiocarbamate (dtc) complex cations with compositions [Co(S2CNEt2)2(dppe)](PF6) (Co-Et), [Co(S2CNPri2)2(dppe)](PF6) (Co-Pr) and [Co(S2CNBun2)2(dppe)](PF6) (Co-Bu) have been synthesized and characterized by microanalysis, spectroscopic methods and crystallographic analysis. The single crystal X-ray diffraction results indicated that in all three complexes, the coordination environment around Co(III) is distorted octahedral and Co(III) is coordinated to four sulfur centers of the two dtc ligands and the two phosphorus centers of the dppe ligand. These complexes serve as precursors to yield cobalt sulfide/cobalt phosphide nano-composites dCo-Et, dCo-Pr and dCo-Bu by solvothermal decomposition of Co-Et, Co-Pr and Co-Bu, respectively. The decomposed materials have been characterized by PXRD and SEM-EDAX and explored as potential electrocatalysts for both oxygen evolution and hydrogen evolution reactions in basic and acidic media, respectively. Catalytic activity is dependent on the precursor complex and best OER and HER activities are observed for dCo-Bu with an η10 of 230 mV and a Tafel slope of 192.11 mV dec−1 for the OER and an η10 of 470 mV and a Tafel slope of 126.21 mV dec−1 for the HER. [ABSTRACT FROM AUTHOR]

Efficient and stable oxygen evolution reaction (OER) electrocatalysts are essential for improving the overall efficiency of water electrolyzers. Iron-doped cobalt phosphide (CoFeP) nanowires are prepared via a one-step solvothermal process using a cobalt metal--organic framework (Co MOF), P4 and dissolved Fe2+. The ion-exchange between Fe2+ and the Co MOF occurs first, and then phosphides are formed. CoFeP exhibits the Co2P phase, and there exists an electronic interaction between Co and Fe. When supported on nickel foam (NF) to catalyze the OER in alkaline solutions, CoFeP/NF exhibits an overpotential of 240 mV at a 10 mA cm-2 OER current density, which is much lower than that of Co2P/NF. Kinetic analyses indicate that the lattice oxygen oxidation mechanism occurs at the CoFeP/NF surface, whereas the adsorbate evolution mechanism dominates at the Co2P/NF surface. The change in the mechanistic pathway is due to the increased acidity of the Co4+ site in CoFeP, which favors the decoupled proton--electron transfer process. Lower apparent activation energy, charge transfer resistance and Tafel slope values, and higher electron rate constants are observed on the CoFeP/NF surface, and the charge redistribution induced by Fe during the OER process alters the adsorption energy of the hydroxyl groups at the Co sites, leading to more facile OER kinetics, as proved by density functional theory calculations. CoFeP/ NF shows good long-term durability in alkaline solutions, and the conversion of surface phosphides to oxides and (oxy)hydroxides is observed. [ABSTRACT FROM AUTHOR]

In this paper, using density functional theory (DFT) methods, we meticulously investigated the structural properties of cobalt phosphide (CoP) and its Cu‐ and Ni‐doped counterpart. Then, on the surfaces of three catalysts, the hydrogen evolution reaction mechanism of ammonia borane (NH3BH3) was examined in turn, and four possible hydrogen evolution reaction paths of NH3BH3 on the catalyst surface were reviewed. The optimal reaction channel for each catalyst was found by comparing the activation energies of the control steps for several reaction paths, and activation energies of the optimal reaction for CoP, Cu, and Ni‐doped CoP were 31.4, 30.4, and 30.8 kcal/mol, respectively. Cu‐ and Ni‐ doped were beneficial to improve the hydrogen evolution reaction activity of NH3BH3. At the same time, the band structures and density of states of the stable catalysts were calculated. The results showed that near the fermi level, the electron cloud density of Cu and Ni‐doped CoP catalysts increased. The energy gap values of the three catalysts are 43.8, 41.0, and 41.7 kcal/mol, respectively, and the energy gap values of Cu and Ni doped CoP catalysts decrease. The energy gap values of the three catalysts are inversely proportional to their catalytic activities. We believe that these two factors together contribute to the increased catalytic activity of the doped CoP. Our results revealed the correlation between the physical properties of CoP and its metal‐doped catalysts and their catalytic activity. [ABSTRACT FROM AUTHOR]

The decomposition of ammonia borane (NH3BH3) to produce hydrogen has developed a promising technology to alleviate the energy crisis. In this paper, metal and non-metal diatom-doped CoP as catalyst was applied to study hydrogen evolution from NH3BH3 by density functional theory (DFT) calculations. Herein, five catalysts were investigated in detail: pristine CoP, Ni- and N-doped CoP (CoPNi-N), Ga- and N-doped CoP (CoPGa-N), Ni- and S-doped CoP (CoPNi-S), and Zn- and S-doped CoP (CoPZn-S). Firstly, the stable adsorption structure and adsorption energy of NH3BH3 on each catalytic slab were obtained. Additionally, the charge density differences (CDD) between NH3BH3 and the five different catalysts were calculated, which revealed the interaction between the NH3BH3 and the catalytic slab. Then, four different reaction pathways were designed for the five catalysts to discuss the catalytic mechanism of hydrogen evolution. By calculating the activation energies of the control steps of the four reaction pathways, the optimal reaction pathways of each catalyst were found. For the five catalysts, the optimal reaction pathways and activation energies are different from each other. Compared with undoped CoP, it can be seen that CoPGa-N, CoPNi-S, and CoPZn-S can better contribute hydrogen evolution from NH3BH3. Finally, the band structures and density of states of the five catalysts were obtained, which manifests that CoPGa-N, CoPNi-S, and CoPZn-S have high-achieving catalytic activity and further verifies our conclusions. These results can provide theoretical references for the future study of highly active CoP catalytic materials. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is a new type of renewable energy that can meet people's growing energy needs and is environmentally friendly. In order to improve the industrial application prospects and electrochemical performance of hydrogen evolution catalysts, extensive research on transition metal materials has been carried out. Among the many catalytic materials, cobalt is an element with potential for the hydrogen evolution reaction (HER) due to its abundant reserves, low cost, and small energy barrier for H adsorption. This review classifies the latest research on cobalt-based catalysts according to the types of compound, including cobalt-based sulfides, phosphides, carbides, borides, oxides, etc., and summarizes the latest research progress of cobalt-based compound catalysts in acidic and alkaline media. Strategies to tune the properties of cobalt-based compound catalysts for high catalytic activity for HER are focused on, including structural engineering, defect engineering, and doping, etc. The advantages and limitations of each modified approach are reviewed. Not only that, but also the catalytic activity and advantages of the catalyst are evaluated by using density functional theory (DFT) calculation-related descriptors, activity evaluation parameters, etc. Finally, limitations and challenges of cobalt-based materials for HER are presented, as well as prospects for future research. This paper aims to understand the chemical and physical factors that affect cobalt-based catalysts, and to find directions for future research on cobalt-based catalysts. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) plays a vital role for the production of pure hydrogen with zero carbon release. Developing high efficiency non-noble metal electrocatalysts could reduce its cost. Here, vanadium doped cobalt phosphide grown on carbon cloth (CC) was synthesized by the low temperature electrodeposition–phosphorization method. The influence of V dopants on the structural, morphological, and electrocatalytic performance of Vx–Co1−x–P composites was also investigated in-depth. Impressively, the optimized amorphous V0.1–Co0.9–P nano-electrocatalyst exhibits outstanding catalytic activity with a low overpotential of 50 mV at a current density of 10 mA cm−2 and a small Tafel value of 48.5 mV dec−1 in alkaline media. The results showed that V dopants in the composite change its crystal structure from the crystalline phase to the amorphous phase, resulting in the introduction of V–O sites, which regulate the electron density of the active sites and the exposure of surface active sites and thus promote the electrocatalytic HER process. This work provides a novel idea for the fabrication of high-efficiency metal phosphide based electrocatalysts. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) is involved in various renewable energy systems, such as water-splitting cells and metal–air batteries. Cobalt phosphide nanomaterials have been reported as promising OER electrocatalysts. Herein, the rational design of advanced nanostructures for nitrogen doped and carbon coated cobalt phosphide hollow nanospheres (CoP@NC HNS) was highly desirable to optimize their electrocatalytic performance. SiO2 nanospheres were used as a sacrificial template for the synthesis of hollow nanospheres composed of ultrathin CoP@NC nanosheet arrays. The hollow nanostructure CoP@NC was coated with a layer of carbon material and the thickness of the shell was about 40 nm. The resultant CoP@NC HNS manifested high electrocatalytic activity towards the OER with low overpotential (320 mV, 10 mA cm−2), small Tafel slope (68 mV dec−1), and remarkable stability in alkaline electrolyte. Remarkably, the CoP@NC HNS still maintained an outstanding performance for the OER at 60 °C. [ABSTRACT FROM AUTHOR]

The high overpotential of the oxygen evolution reaction (OER) and the undesirable chlorine evolution reaction (ClER) severely limit the hydrogen production efficiency of seawater electrolysis. The organic electrooxidation reactions, involving C–H bond oxidation with low bond dissociation energy in the rate-limiting step, can possess lower oxidation potential than the OER as well as prevent the ClER. Herein, we demonstrate a strategy for replacing the sluggish OER by thermodynamically favorable biomass oxidation for scaling up the electrolysis of alkaline seawater. A xylose electrooxidation reaction (XOR) holds great promise for superseding the OER in seawater electrolysis, which not only simultaneously produces valuable formic acid and hydrogen, but also improves energy utilization. By utilizing NiCoP metal phosphide as the bifunctional electrode, the XOR shows an apparent overpotential reduction of 290 mV at 100 mA cm−2 as compared with the OER in the alkaline seawater electrolyte. Furthermore, the xylose-assisted seawater electrolysis exhibits a high formic acid selectivity of at least 94.6% and a high hydrogen production rate of 150 mL cm−2. This work provides a universal and an effective pathway for hydrogen production from seawater and biomass upgrading. [ABSTRACT FROM AUTHOR]

In this paper, using density functional theory (DFT) methods, we meticulously investigated the structural properties of cobalt phosphide (CoP) and its Cu‐ and Ni‐doped counterpart. Then, on the surfaces of three catalysts, the hydrogen evolution reaction mechanism of ammonia borane (NH3BH3) was examined in turn, and four possible hydrogen evolution reaction paths of NH3BH3 on the catalyst surface were reviewed. The optimal reaction channel for each catalyst was found by comparing the activation energies of the control steps for several reaction paths, and activation energies of the optimal reaction for CoP, Cu, and Ni‐doped CoP were 31.4, 30.4, and 30.8 kcal/mol, respectively. Cu‐ and Ni‐ doped were beneficial to improve the hydrogen evolution reaction activity of NH3BH3. At the same time, the band structures and density of states of the stable catalysts were calculated. The results showed that near the fermi level, the electron cloud density of Cu and Ni‐doped CoP catalysts increased. The energy gap values of the three catalysts are 43.8, 41.0, and 41.7 kcal/mol, respectively, and the energy gap values of Cu and Ni doped CoP catalysts decrease. The energy gap values of the three catalysts are inversely proportional to their catalytic activities. We believe that these two factors together contribute to the increased catalytic activity of the doped CoP. Our results revealed the correlation between the physical properties of CoP and its metal‐doped catalysts and their catalytic activity. [ABSTRACT FROM AUTHOR]

Cobalt phosphide has excellent electrical conductivity, metallic properties, and thermal stability. However, its application is limited due to the few active sites exposed in electrochemical reactions and poor structural stability. Herein, we adopt the strategies of material compounding and structural design to construct CoP@Ni(OH)2 bilayer nanosheets. The bilayer nanosheet structure can provide abundant transport paths for electrons and ions while also exposing more electroactive sites. In addition, the close contact and mutual support of the bilayer nanosheet structure can significantly alleviate material morphological collapse during charging/discharging processes, improving the cycle stability. The advantages of multiple components were combined in CoP@Ni(OH)2 to provide multiple valances for the faradaic redox reactions. The CoP@Ni(OH)2 manifested a specific capacity of 1697.8 C g−1 at 1 A g−1 and maintained a high rate capability of 35.0% even at 20 A g−1. Moreover, the electrode, had great cycling stability, retaining 83.9% of its capacity at 6 A g−1 after 7000 cycles. The asymmetric supercapacitor made of CoP@Ni(OH)2//activated carbon delivered 53.2 W h kg−1 at 800 W kg−1. [ABSTRACT FROM AUTHOR]

Developing high-performance and low-cost self-supporting electrodes as pH-universal electrocatalysts for the hydrogen-evolution reaction (HER) and realizing high-quality hydrogen production at a high current density are highly desirable, but are hugely challenging. We created a self-supporting electrode with a coupled hierarchical heterostructure by simple electrodeposition followed by sulfurization. It comprised oxygen-deficient molybdenum oxide (MoO3−x) and cobalt phosphide (CoP) on nickel foam (NF), which represented a highly active pH-universal electrocatalyst for the HER at a high current density. Benefiting from a plethora of catalytic active sites, improved interfacial charge transfer, and strong electronic interaction, this type of MoO3−x@CoP/NF electrode delivered a superior catalytic performance. Overpotentials of only 100 mV, 135 mV, and 400 mV were needed to realize a high current density of 1 A cm−2 in alkaline, acid and neutral media, respectively, which were superior to those of most other well-developed materials based on non-noble metals. Our experimental work demonstrates the synergistic advantages of a MoO3−x@CoP heterostructure for improving the intrinsic catalytic performance but also paves a new path for the rational design of advanced electrodes for hydrogen generation in a wide range of pH conditions. [ABSTRACT FROM AUTHOR]

The development of efficient, durable and economical catalysts based on non-precious metals for the controllable and fast hydrogen evolution from chemical hydrogen storage materials is highly desirable for the hydrogen economy. Herein, we introduce an advanced catalytic system by in situ encapsulating cobalt phosphide (CoP) nanoparticles into a quasi-metal–organic framework (quasi-Co-MOF-74) through a smart pyrolysis method. The designed synergic structure of CoP@quasi-Co-MOF-74 facilitates the efficient adsorption and activation of reactants, and achieves superior catalytic activity for the dehydrogenation of ammonia borane (AB). The extremely high hydrogen generation rate (HGR) of 9790 mL min−1 gcat−1 achieved by this catalytic system is 13.1, 4.4, and 46.5 times higher than that of quasi-Co-MOF-74, CoP, and CoP@C counterparts, respectively. Furthermore, CoP@quasi-Co-MOF-74 also delivers a high turnover frequency (TOF) of 55.9 min−1 and a low activation energy of 38.22 kJ mol−1 for the catalytic hydrolysis of AB, which compares favorably to most of the previously reported transition metal phosphide and cobalt-based catalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic H2O-to-H2(g) and –H2O2(aq) (2H2O(l) → H2(g) + H2O2(aq)) by a two-electron reaction is kinetically feasible. The proton-coupled two-electron transfer induced a photocatalytic oxygen reduction reaction (ORR) from oxygen and water is also an accessible path for the safe production of H2O2. It is thus desirable to synthesize effective photocatalysts that yield H2O2 by the coupling of two-electron transfer water oxidation (+1.23 VNHE) and ORR (+0.68 VNHE). In this work, new g-C3N4/BiOI S-scheme heterojunctions with co-catalyst cobalt phosphide (CoP) (BiOI/g-C3N4/CoP) were prepared for the photocatalytic H2O-to-H2O2 reactions. The BiOI/g-C3N4/CoP heterojunctions can enhance visible light absorption and reduce electron–hole pair recombination rates. Because of the water splitting by two-electrons and reduction of oxygen, the BiOI/g-C3N4/CoP heterojunctions have a better photocatalytic H2O-to-H2O2 yield than with the BiOI/g-C3N4 heterojunction by 3.0–8.4 times. With more CoP (i.e., 19 wt%) on the BiOI/g-C3N4, the BiOI/g-C3N4/(CoP)0.19 heterojunction generates more photocatalytic H2O2 with higher formation rate constant (kf), equilbrium constant (K), and a lower decomposition rate constant (kd). This new, low-cost and ready-prepared BiOI/g-C3N4/CoP S-scheme heterojunction has a high efficiency for the reversible photocatalytic H2O-to-H2O2 reaction, which could be feasibly used for applications in H2O2-fuel cells for electricity using solar energy. [ABSTRACT FROM AUTHOR]

Zinc-doped cobalt nickel sulfides coupled with polypyrrole hollow nanospheres grown on carbon paper (Zn-CoNiS/PHS/CP) were developed by unipolar pulse electrodeposition (UPED) method as efficient and stable electrocatalysts for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and overall water splitting in neutral media for the first time. With abundant active sites intrigued by moderate Zn doping, the optimized Zn 10 -CoNiS delivers improved catalytic performance with small overpotentials of 213 mV and 414 mV to achieve the current densities of 10 mA cm−2 for HER and OER respectively, and outstanding long-term stability. The water electrolyzer device with Zn 10 -CoNiS as both anode and cathode delivers a current density of 10 mA cm−2 at a cell voltage of 1.896 V in neutral media. The low charge transfer resistance of Zn-CoNiS and confinement effect of 2D Ni 9 S 8 /Co 9 S 8 nanosheets on 0D ZnS nanodots endow the bifunctional electrocatalysts with efficient activity and high stability, providing a competitive candidate for green hydrogen production. [Display omitted] • Unipolar pulse electrodeposition is used to construct cation-doped bimetallic sulfide. • Zn-CoNiS shows advanced catalytic activity and high stability for both HER and OER. • Doping of Zn optimizes electronic structure and enhances conductivity of Ni 9 S 8 /Co 9 S 8. • 0D/2D confinement effect promotes long-term stability of Zn-CoNiS in neutral media. • Zn 10 -CoNiS bifunctional catalyst delivers superb overall water splitting performance. [ABSTRACT FROM AUTHOR]

• The heterostructures were synthesized via electrospinning, sulfuration and subsequent hydrothermal process. • Low overpotential of 52–93 mV at the current density of 10 mA/cm2 and small Tafel slope of 61–86 mV/dec were achieved. • More active sites and synergistic effect contributed to the enhanced HER performance. Transition metal sulfides have attracted much attraction in electrochemical water splitting owing to their low cost and unlimited availability. The formation of heterostructures has been demonstrated to be an effective manner to enhance the electrocatalytic performance. In this paper, hierarchical nanowires of MoS 2 @transition metal sulfide (FeS, CuS, CoS 2 and SnS 2) heterostructures were fabricated via simple electrospinning, sulfuration and subsequent hydrothermal process. X-ray diffraction and X-ray photoelectron spectroscopy were utilized to character the crystal structures and chemical compositions of as-prepared electrocatalysts. Scanning electron microscope and transmission electron microscope characterization results confirmed the existence of heterostructures in the MoS 2 @transition metal sulfide hybrid nanowires. Benefitting from the synergistic effect and the increased active sites, the as-prepared MoS 2 @transition metal sulfide (FeS, CuS, CoS 2 and SnS 2) heterostructures exhibited superior electrocatalytic HER performance. The MoS 2 @transition metal sulfides (FeS, CuS, CoS 2 and SnS 2) delivered the overpotential of 52 mV, 62 mV, 88 mV and 93 mV at the current density of 10 mA/cm2, and the Tafel slope of 64 mV/dec, 82 mV/dec, 73 mV/dec and 70 mV/dec in acid media. This work provides a novel way to optimize the HER activity of nanostructured MoS 2. [ABSTRACT FROM AUTHOR]

Under the gravity of future socio-economic development, the viability of water electrolysis still hinges on the accessibility of stable earth-abundant electrocatalysts and net energy efficiency. This work emphasizes the design and synthesis of two newly developed cobalt(II) complexes, [Co(HL)2(NCS)2] (Comono) and [Co2(L)3(CH3OH)]ClO4 (Codi), with a (N,O)-donor ligand, HL (2-methoxy-6-(((2-methoxyphenyl)imino)methyl)phenol). The study delves into understanding their structural, morphological, magnetic, and charge transport characteristics. Moreover, the study explores the potential of these complexes in catalyzing hydrogen production through heterogeneous electrocatalysis. The X-ray crystal structure of Comono reveals the octahedral geometry of the Co(II) ion, adopting two HL units and two NCS− units. The Codi complex exhibits a doubly-phenoxo-O-bridged (μ1,1) dinuclear complex, forming a typical octahedral geometry for both the Co(II) centres in coupling with three units of L−. Temperature-dependent magnetic susceptibility measurements showed that all of the Co(II) ion in Comono shows a typical paramagnetic behaviour for high spin octahedral Co(II) ions while the Co(II) centres in Codi are coupled with doubly-phenoxo-bridges bearing weak ferromagnetic characteristics at low temperature. Electron transport properties of the Co(II) complex-mediated Schottky device address the superior carrier mobility (μ) for Codi (9.21 × 10−5) over Comono (2.02 × 10−5 m2 v−1 s−1) with respective transit times of 1.70 × 10−9 and 7.77 × 10−9 s. Additionally, electron impedance spectral analysis supports the lower electrical transport resistance of Codi relative to Comono. The heterogeneous electrocatalytic HER activity of Codi and Comono in 0.1 M KOH shows excellent electrocatalytic efficiency in terms of the various electrochemical parameters. Constant potential electrolysis, multi-cycle CVs, and post-HER analysis reveal the pre-catalytic nature of the complexes, which in turn delivers Co3O4 nanoparticles as the active catalysts for efficient hydrogen evolution. [ABSTRACT FROM AUTHOR]

Transition metal phosphides have been widely used as electrocatalysts for water splitting. In particular, cobalt phosphide electrocatalysts play an important part in the oxygen evolution reaction. Here, two kinds of CoP with different nanostructures, CoP-MA and CoP-GC (MA = methylamine and GC = guanidine carbonate), were successfully prepared by a two-step method, including calcination of the corresponding Co-based metal formate frameworks, [Amine][Co(HCOO)3] (Amine = CH3NH3 and C(NH2)3), in air and the subsequent low temperature phosphating process. As OER catalysts, the CoP nanostructures show strong electrochemical structure-dependent properties. Electrochemical tests show that nanoparticle based CoP-MA micro-cubes required an overpotential of 340 mV at a current density of 10 mA cm−2, while nanosheet based CoP-GC micro-cubes only required an overpotential of 310 mV at the same current density. Importantly, the two CoP micro-cubes have a similar morphology but different structures, providing a direct side-by-side evaluation of their OER activities. The comparisons of the same metal phosphide OER catalysts with the same morphology but different structures are of great significance in identifying the key material characteristics that lead to high activity. [ABSTRACT FROM AUTHOR]

Designing an efficient electrocatalyst for facile oxygen reduction reaction (ORR) is essential to achieve higher fuel cell performance. Herein, we demonstrate a simple in situ process to synthesize cobalt sulfide-decorated N and S co-doped mesoporous carbon (Co9S8/N,S-MC) and evaluated its electrocatalytic activity for ORR in alkaline media. Porous carbon has great potential as a support material due to its well-defined porous architecture, which facilitates the mass transport. Here, the Co9S8/N,S-MC electrocatalyst was designed through a soft template route using pluoronic-F127 as a structure-directing agent, phloroglucinol-formaldehyde resin as a carbon source, and thiourea and cobalt acetate as N, S and Co sources, respectively. The combined effects of cobalt sulfide, heteroatoms and the well-defined porous architecture of mesoporous carbon resulted in the excellent ORR performance of the Co9S8/N,S-MC catalyst. Consequently, the optimized Co9S8/N,S-MC catalyst exhibited an onset potential and limiting current density of 0.87 V vs. RHE, and 3.40 mA cm−2, respectively. These values were very close to those of the commercial Pt–C catalyst with only a difference of 50 mV and 80 mA cm−2, but the Co9S8/N,S-MC catalyst also showed a 30 mV higher half-wave potential and excellent long-term stability compared to those of the commercial Pt/C catalyst. These interesting results suggested the good potential application of Co9S8/N,S-MC as ORR electrocatalysts with longer stability in fuel cells. [ABSTRACT FROM AUTHOR]

Metal phosphides have been proved to be potential theranostic agents of tumors. However, the limitations of single-modal imaging or the treatment effect of such materials need to be further improved. Here, we successfully prepared polyvinylpyrrolidone-modified bimetallic nickel cobalt phosphide (NiCoP/PVP) nanoparticles as a theranostic agent of tumors. Owing to the different types of magnetic properties of Ni and Co components, T1- and T2-weighted magnetic resonance imaging (MRI) could be simultaneously achieved to compensate the low accuracy brought about by single-modal MRI. In addition, NiCoP/PVP possesses excellent photothermal properties owing to its obvious absorption in the near-infrared (NIR) region, which endows NiCoP/PVP with high photothermal conversion efficiency (PCE) to serve as a photothermal agent for tumor ablation. Therefore, NiCoP/PVP is a promising theranostic agent for accurate diagnosis and effective treatment of tumors. [ABSTRACT FROM AUTHOR]

Materials containing cobalt phosphide nanoparticles are among the most promising electrocatalysts for the hydrogen evolution reaction in terms of compromise between activity, cost, and durability. A simple and effective approach to fabricating a nanocomposite of graphene–phosphorene structures decorated with CoP nanoparticles 2–5 nm in size is proposed. The nanocomposite was fabricated by the electrochemical exfoliation of black phosphorus followed by the solvothermal synthesis. The synthesis was carried out in the presence of few-layer graphene structures doped with nitrogen atoms in the solution containing Co2+ ions. The electrocatalyst exhibited high activity and stability towards hydrogen evolution reaction in the acidic medium. In order to achieve a current density of 10 mA cm–2, an overpotential of ~220 mV was required, and the Tafel slope was ~63 mV dec–1. It is suggested that this result is due to both the synergistic effect of the interaction between graphene and phosphorene structures and the electrocatalytic activity of CoP nanoparticles, which are located at the edges of phosphorene structures. [ABSTRACT FROM AUTHOR]

The controllable and safe hydrogen storage technologies are widely recognized as the main bottleneck for the accomplishment of sustainable hydrogen energy. Ammonia borane (AB) has regarded as a competitive candidate for chemical hydrogen storage. However, developing efficient yet high-performance catalysts towards hydrogen evolution from AB hydrolysis remains an enormous challenge. Herein, cobalt phosphide nanosheets are synthesized by a facile salt-assisted along with low-temperature phosphidation strategy for simultaneously modulating its morphology and electronic structure, and function as hydrogen evolution photocatalysts. Impressively, the Co2P nanosheets display extraordinary performance with a record high turnover frequency of 44.9 min-1, outperforming most of the noble-metal-free catalysts reported to date. This remarkable performance is attributed to its desired nanosheets structure, featuring with high specific surface area, abundant exposed active sites, and short charge diffusion paths. Our findings provide a novel strategy for regulating metal phosphides with desired phase structure and morphology for energy-related applications and beyond. [ABSTRACT FROM AUTHOR]

In this study, the successful synthesis of bimetallic nickel/cobalt phosphide nanosheets (Ni-Co-P NSs) via the hydrothermal method and the subsequent high-temperature phosphorization process were both confirmed. Ni-Co-P NSs exhibited excellent electrocatalytic activity for the electrochemical non-enzymatic DA sensing. The surface morphologies and physicochemical properties of Ni-Co-P NSs were characterized by atomic force microscopy (AFM), field-emission scanning (FESEM), field-emission transmission electron microscopy (FETEM), and X-ray diffraction (XRD). Further, the electrochemical performance was evaluated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The metallic nature of phosphide and the synergistic effect of Ni/Co atoms in Ni-Co-P NSs provided abundant catalytic active sites for the electrochemical redox reaction of DA, which exhibited a remarkable consequence with a wide linear range from 0.3~50 μM, a high sensitivity of 2.033 µA µM−1 cm−2, a low limit of detection of 0.016 µM, and anti-interference ability. As a result, the proposed Ni-Co-P NSs can be considered an ideal electrode material for the electrochemical non-enzymatic DA sensing. [ABSTRACT FROM AUTHOR]

Seawater electrolysis is a viable method for producing hydrogen on a large scale and low-cost. However, the catalyst activity during the seawater splitting process will dramatically degrade as salt concentrations increasing. Herein, CoP is discovered that could reject chloride ions far from catalyst in electrolyte based on molecular dynamic simulation. Thus, a binder-free electrode is designed and constructed by in-situ growth of homogeneous CoP on rGO nanosheets wrapped around the surface of Ti fiber felt for seawater splitting. As expected, the as-obtained CoP/rGO@Ti electrode exhibits good catalytic activity and stability in alkaline electrolyte. Especially, benefitting from the highly effective repulsive Cl− intrinsic characteristic of CoP, the catalyst maintains good catalytic performance with saturated salt concentration, and the overpotential increasing is less than 28 mV at 10 mA cm−2 from 0 M to saturated NaCl in electrolyte. Furthermore, the catalyst for seawater splitting performs superior corrosion-resistance with a low solubility of 0.04%. This work sheds fresh light into the development of efficient HER catalysts for salinity tolerance hydrogen evolution. Seawater electrolysis for hydrogen production is limited by the poor salinity tolerance of catalysts. CoP was found to repel chlorine while attracting H2O molecules to form a thin layer on the catalyst surface, thus constructing a corrosion-resistant CoP/rGO@Ti catalyst for seawater splitting. [ABSTRACT FROM AUTHOR]

The search for new hydrogen evolution reaction (HER) electrocatalysts with lower cost and higher activity and stability than noble metal catalysts is essential. In this regard cobalt phosphide is considered one of the most promising nanomaterials. The present work proposes a simple and efficient method for the synthesis of a nanocomposite of graphene–phosphorene structures decorated with CoP nanoparticles 2–5 nm in size via the electrochemical exfoliation of black phosphorus carried out in the presence of nitrogen-doped few-layer graphene structures and followed by solvothermal synthesis in a Co2+-containing solution. The obtained CoP/EEBP/N-FLGS nanocomposite demonstrates high electrocatalytic activity and stability towards HER in an alkaline medium. The nanocomposite is characterized by an overpotential of 190 mV at a current density of 10 mA cm−2 as well as a small Tafel slope (78 mV dec−1). These characteristics make the CoP/EEBP/N-FLGS nanocomposite superior to most electrocatalysts based on cobalt phosphides. The results of this study could be in demand for the future design and improvement of HER electrocatalysts. [ABSTRACT FROM AUTHOR]

It has become a consensus to study transition metal phosphides with abundant earth reserves and good electrochemical properties as electrode materials for supercapacitors. Among them, cobalt phosphide is particularly attractive because of its good electrical conductivity and theoretical specific capacity. Therefore, cobalt phosphide composites were prepared by hydrothermal reaction and phosphating reaction in this paper. Due to the synergistic effect of different components and the interfacial effect between the components, the ion transport and charge transfer kinetics of the prepared Co/Co 2 P/CoP electrode are both improved, which exhibits excellent electrochemical performance. At the current density of 1 A g−1, the prepared Co/Co 2 P/CoP electrode material has a specific capacitance of 193.3 mA h g−1, after 6000 cycles of charge and discharge at the current density of 2 A g−1, the specific capacitance maintains at 80 %. An asymmetric supercapacitor was assembled with the prepared material as the positive electrode and activated carbon as the negative electrode, which can provide an energy density of 37.87 W h kg−1 at a power density of 799.6 W kg−1. At the current density of 1 A g−1, the assembled supercapacitor can maintain 80 % of the initial specific capacitance after 5000 cycles. This provides ideas for future research on this type of energy storage materials. [Display omitted] • The Co/Co 2 P/CoP exhibits good electrochemical performance due to the synergistic effect of the different components. • The activity and crystallinity of the material have been improved to a certain extent due to the addition of metallic cobalt. • The assembled asymmetric supercapacitors using the Co/Co 2 P/CoP and active carbon exhibits outstanding performance. [ABSTRACT FROM AUTHOR]

The application of microwave absorbing materials is one of the important means to reduce electromagnetic pollution. Transition metal phosphides as absorbers with high conductivity attract researchers' interest. Therefore, in this paper, the novel cobalt phosphide wrapped by reduced graphene oxide (CoP/RGO) were prepared by simple hydrothermal and phosphating reaction. Meanwhile, the introduction of RGO is beneficial to enhance the conductive loss and polarization loss of materials. Compared with most of the reported transition metal phosphate-based absorbents, CoP/RGO has a better microwave absorption (MA) performance. The minimum reflect loss (RL min) value can reach − 52.60 dB with 2.05 mm, and the maximum effective absorption bandwidth (EAB, RL<−10 dB) can reach 5.04 GHz at 2.25 mm. The superior MA performance of CoP/RGO composites makes it possible to be a candidate as an absorber. [Display omitted] • A novel CoP/RGO composite was prepared by hydrothermal and phosphating reaction. • It shows high conductivity loss and polarization loss. • The RLmin value is − 52.60 dB and the maximum EAB is 5.04 GHz. [ABSTRACT FROM AUTHOR]

Electrochemical nitrate reduction to ammonia is a promising alternative strategy to the traditional Haber-Bosch process but suffers from a low Faradaic efficiency and limited ammonia yield due to the sluggish multi-electron/proton-involved steps. Herein, we report a typical hollow cobalt phosphide nanosphere electrocatalyst assembled on a self-supported carbon nanosheet array synthesized with a confinement strategy that exhibits an extremely high ammonia yield rate of 8.47 mmol h−1 cm−2 through nitrate reduction reaction, which is highly superior to previously reported values to our knowledge. In situ experiments and theoretical investigations reveal that the dynamic equilibrium between the generation of active hydrogen on cobalt phosphide and its timely consumption by nitrogen intermediates leads to a superior ammonia yield with a high Faradaic efficiency. This unique insight based on active hydrogen equilibrium provides new opportunities for large-scale ammonia production through electrochemical techniques and can be further used for carbon dioxide capture. While electrochemical conversion of nitrate to ammonia offers a renewable means to remediate waste compounds, it is challenging to achieve selective catalysis. Here, authors demonstrate a strategy to improve electrocatalytic ammonia production using cobalt phosphide on carbon nanosheet arrays. [ABSTRACT FROM AUTHOR]

The development of efficient electrocatalysts for water splitting is needed to boost green hydrogen production. Herein, a ZIF-67-derived La-doped CoP (La–CoP) is prepared by a facile solvothermal–phosphorization process as an efficient bifunctional water-splitting catalyst. The introduction of La into CoP enables the modulation of the electronic configuration of Co and P, facilitating the charge transfer and thus lowering the energy barrier of the rate-limiting step to catalyze oxygen and hydrogen evolution reactions (OER and HER). The optimized La–CoP delivers good OER and HER activities as manifested by small overpotentials of 270 and 109 mV, respectively, to reach the current density of 10 mA cm−2. The electrolyzer constructed using La–CoP as both cathode and anode requires a cell voltage of 1.608 V at 10 mA cm−2 in alkaline media, which outperforms a noble metal-based (Pt/C and RuO2) electrolyzer. This work provides useful perspectives for fabricating efficient electrocatalysts by modulating the electronic structure of active sites. [ABSTRACT FROM AUTHOR]

Non-precious metallic electrocatalysts are attracting attention for use in the hydrogen evolution reaction (HER) because they are inexpensive, highly efficient, and durable. Notably, carbon-based catalysts, such as transition metal and heteroatomic-doped carbon materials, are promising candidates to replace precious metal catalysts. The functionalization of the carbon matrix with nitrogen and cobalt is an effective way to develop the electrocatalytic properties of carbon-based catalysts. However, simple and cheaper synthesis methods for catalysts have not been fully investigated. Herein, we report on a cobalt oxide nanoparticle-decorated nitrogen (N)-doped carbon catalyst synthesized by a simple two-step method using spent coffee grounds (SCG). In the first step, SCG-derived carbon (SCG-KU) was obtained by pyrolysis under high temperatures with urea and potassium hydroxide. Second, SCG-KU was functionalized with urea and cobalt chloride. We determined that Co@SCG-KU had a high Brunauer–Emmett–Teller (BET) surface area (1413.2 m2 g−1); cobalt nanoparticles were uniformly distributed in hierarchically porous carbon and surrounded by graphitic carbon. Electrochemical performance results confirmed that the Co@SCG-KU possessed a high electrocatalytic effect (0.28 V at 10 mA cm−2) and better HER stability (at 5.0 mA cm−2 for 8 h). Our results demonstrate a simple, eco-friendly, and low-cost method to prepare a more efficient carbon-based electrocatalyst from SCG in hydrogen evolution applications. [ABSTRACT FROM AUTHOR]

It is an indisputable fact that electrocatalytic activity is always improved by introducing defects into nanomaterials. Thus, this study demonstrates a simple strategy for a defect-rich and porous cobalt phosphide nanowire array electrocatalyst derived from a MOF material on a nickel foam, which drives water splitting well in alkaline media. Excitingly, p-CoP/NF shows an excellent catalytic performance toward the hydrogen evolution reaction with an ultralow overpotential of 35 mV to achieve 10 mA cm−2. Similarly, it is capable of the oxygen evolution reaction and reaches a current density of 10 mA cm−2 with an overpotential of 253 mV. Furthermore, when the anode and cathode of a two-electrode electrolytic cell are both assembled from p-CoP/NF electrodes, this cell requires a voltage of only 1.55 V to afford a current density of 10 mA cm−2 and exhibits satisfactory durability, which fully demonstrates the potential application of p-CoP/NF electrodes for water splitting. [ABSTRACT FROM AUTHOR]

Summary: For green‐hydrogen production through a promising electrolytic water splitting, cobalt phosphide is in the spotlight as one of the new affordable materials to replace currently used noble‐metal catalysts. In this study, we fabricate hollow cobalt phosphide (CoP) nanofibers with advanced nanostructure using electrospinning and phosphidation. Due to their unique architecture and oxygen‐rich surface characteristics, the novel hollow‐structure CoP nanofibers effectively increase hydrogen evolution reaction catalytic activity with the low overpotentials of 91 mV (for acid) and 63 mV (for alkaline). Using in situ Raman spectroscopy, it is confirmed that high‐oxygen‐containing CoP catalysts could transform the CoOOH phase under alkaline conditions, which offer faster water dissociation kinetics. Furthermore, CoP nanofibers exhibited excellent durability even after 30000th accelerated degradation test cycles and overall water splitting for 40 h. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoP/g-C 3 N 4 hybrid photocatalyst was prepared in which CoP acts as a noble-metal-free HER cocatalyst. • CoP/g-C 3 N 4 composite exhibits high dye-sensitized photocatalytic HER activity and stability. • Photogenerated electrons can effectively transfer among EY, g-C 3 N 4 and CoP. • The AQY of 56.3% at 420 nm is achieved under the optimized conditions. In this paper, CoP/g-C 3 N 4 composite photocatalysts were prepared, in which CoP was used as a noble-metal-free cocatalyst. Using dye Eosin Y (EY) as the sensitizer and triethanolamine (TMA) as the electron donor, the performance of the photocatalytic H 2 evolution reaction (HER) under visible light (λ ≥ 420 nm) was investigated. When the loading of CoP is 5 wt%, the CoP(5 wt%)/g-C 3 N 4 composite shows the best photocatalytic HER performance, even better than that of Pt(5 wt%)/g-C 3 N 4. The apparent quantum yield (AQY) achieves 56.3% under 420 nm light irradiation, one of the best values reported for noble-metal-free cocatalysts in the dye-sensitized HER system, and the catalyst also exhibits good stability under 36 h of irradiation. The high activity and stability of CoP(5 wt%)/g-C 3 N 4 are the results of efficient electron transfer among photoexcited EY, g-C 3 N 4 and CoP, and the excellent HER activity of CoP. [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) have demonstrated great potential for accelerating the electrocatalytic hydrogen evolution reaction (HER). Herein, we present the facile synthesis of the nickel cobalt phosphide (NiCoP) electrocatalyst with a 3D nanoporous structure formed by dealloying and combined low temperature chemical vapor deposition (CVD) phosphorization. Its activity is attributed to the large specific surface area of the dealloyed substrate and the good intrinsic activity of the bimetallic phosphides. The as-prepared NiCoP is found to exhibit a low hydrogen evolution reaction overpotential of 130 mV (η10) and a small Tafel slope of 93 mV dec-1 in an alkaline medium. Moreover, no significant deactivation is observed even after running for at least 2000 CV cycles, suggesting excellent stability. The bimetallic phosphide also shows superior HER activity compared with single-metal phosphides, such as cobalt phosphide and nickel phosphide. It is expected that our work could provide a new idea for the design of highly active non-noble-metal materials for the electrocatalytic HER. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries have aroused great interest in the context of rechargeable batteries, while the shuttle effect and sluggish conversion kinetics severely handicap their development. Defect engineering, which can adjust the electronic structures of electrocatalyst, and thus affect the surface adsorption and catalytic process, has been recognized as a good strategy to solve the above problems. However, research on phosphorus vacancies has been rarely reported, and how phosphorus vacancies affect battery performance remains unclear. Herein, CoP with phosphorus vacancies (CoP‐Vp) is fabricated to study the enhancement mechanism of phosphorus vacancies in Li–S chemistry. The derived CoP‐Vp features a low Co‐P coordination number and the introduced phosphorus vacancies mainly exist in the form of clusters. The obtained CoP‐Vp can reinforce the affinity to lithium polysulfides (LiPSs) and thus the shuttle effect can be restrained. In addition, the reduced reaction energy barriers and the promoted diffusion of Li+ can accelerate redox kinetics. Electrochemical tests and in situ Raman results confirm the advantages of phosphorus vacancies. The S/CNT‐CoP‐Vp electrode presents outstanding cycling performance and achieves a high capacity of 8.03 mAh cm−2 under lean electrolyte condition (E/S = 5 μLE mg−1S). This work provides a new insight into improving the performance of Li–S batteries through defect engineering. [ABSTRACT FROM AUTHOR]