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The development of low-cost, high-performance anode materials for Li-ion batteries (LIBs) is imperative to meet the ever-increasing demands for advanced power sources. Here we report our findings on the design, synthesis, and characterization of a new cation-disordered ZnSiP2 anode. When tested in LIBs, the disordered phase of ZnSiP2 demonstrates faster reaction kinetics and higher energy efficiency than the cation-ordered phase of ZnSiP2. The superior performance is attributed to the greater electronic and ionic conductivity and better tolerance against volume variation during cycling, as confirmed by theoretical calculations and experimental measurements. Moreover, the cation-disordered ZnSiP2/C composite exhibits excellent cycle stability and superior rate capability. The performance surpasses all reported multi-phase anodes studied. Further, a number of the cation-disordered phases in the Zn(Cu)-Si-P family with a wide range of cation ratios show similar performance, achieving large specific capacities and high first-cycle coulombic efficiency while maintaining desirable working potentials for enhanced safety.

Si‐based anodes with a stiff diamond structure usually suffer from sluggish lithiation/delithiation reaction due to low Li‐ion and electronic conductivity. Here, a novel ternary compound ZnSi2P3 with a cation‐disordered sphalerite structure, prepared by a facile mechanochemical method, is reported, demonstrating faster Li‐ion and electron transport and greater tolerance to volume change during cycling than the existing Si‐based anodes. A composite electrode consisting of ZnSi2P3 and carbon achieves a high initial Coulombic efficiency (92%) and excellent rate capability (950 mAh g−1 at 10 A g−1) while maintaining superior cycling stability (1955 mAh g−1 after 500 cycles at 300 mA g−1), surpassing the performance of most Si‐ and P‐based anodes ever reported. The remarkable electrochemical performance is attributed to the sphalerite structure that allows fast ion and electron transport and the reversible Li‐storage mechanism involving intercalation and conversion reactions. Moreover, the cation‐disordered sphalerite structure is flexible to ionic substitutions, allowing extension to a family of Zn(Cu)Si2+xP3 solid solution anodes (x = 0, 2, 5, 10) with large capacity, high initial Coulombic efficiency, and tunable working potentials, representing attractive anode candidates for next‐generation, high‐performance, and low‐cost Li‐ion batteries.

Ge is considered a promising anode candidate for Li-ion batteries (LIBs); however, its practical applicability is hindered by the relatively slow Li-ion diffusion owing to the stiffness of the diamond-like structure. Inspired by little difference in electronegativity between Ge and P, we have designed a novel layered GeP anode for LIBs, which can be readily synthesized using a mechano-chemical method and a subsequent low-temperature annealing. In particular, GeP demonstrates the best performances among all Ge-based anode materials studied, attributed to its fast Li-ion diffusion compared to Ge counterpart and a unique Li-storage mechanism that involves intercalation, conversion, and alloying, as confirmed by XRD, TEM, XPS, and Raman spectroscopy. Specially, the initial layered crystal structure of GeP can be reconstructed during charging due to its low formation energy, thus offering remarkable reversibility during cycling. Further, this study implies that the formation energy of crystal structures could be an important parameter for strategic design of large-capacity anode materials for LIBs.

Finding low-cost and large-capacity anode materials to replace the commercially available graphite is an urgent need to meet the ever-increasing demand for high energy density Li-ion batteries (LIBs). Due to their suitable working potential, high theoretical capacity and low polarization, phosphides have attracted increasing interest as promising anode candidates for LIBs. However, phosphides suffer from large volume variation and low ionic and electronic conductivity, limiting the long-term cycling stability and rate capability. Herein, we report ZnP2/C derived from alfa-ZnP2 (tetragonal) and graphite as a highly reversible anode for LIBs. Alfa-ZnP2 (tetragonal) has been found to more easily form an amorphous composite with graphite with P-C bonds compared to Zn3P2. The amorphous structure could dramatically reduce the risk of fracture during cycling, profiting from an isotropic stress and the P-C bonds could enhance the Li-ion and electron transfer capability. Therefore, the ZnP2/C composite demonstrates significantly attractive performance in terms of reaction kinetics, energy efficiency and cycling stability with a specific capacity of 1270 mA h g-1 after 2730 cycles, making it superior to other Zn-P compounds and even other transition metal phosphide anodes. The highly reversible lithium storage capability of the ZnP2/C composite can be mainly attributed to the pseudocapacitive contribution. Additionally, the Li-ion full cell LiCoO2//ZnP2/C delivers 1200 mA h g-1 even after 200 cycles with an average working potential of 3.5 V, demonstrating its potential for application in next-generation Li-ion batteries. Broadly, this work would open an avenue for selecting appropriate phases and designing structural engineering with new chemical bonds to achieve ultralong cycling stability and ultrahigh rate performance.

Si‐based anodes with a stiff diamond structure usually suffer from sluggish lithiation/delithiation reaction due to low Li‐ion and electronic conductivity. Here, a novel ternary compound ZnSi2P3 with a cation‐disordered sphalerite structure, prepared by a facile mechanochemical method, is reported, demonstrating faster Li‐ion and electron transport and greater tolerance to volume change during cycling than the existing Si‐based anodes. A composite electrode consisting of ZnSi2P3 and carbon achieves a high initial Coulombic efficiency (92%) and excellent rate capability (950 mAh g−1 at 10 A g−1) while maintaining superior cycling stability (1955 mAh g−1 after 500 cycles at 300 mA g−1), surpassing the performance of most Si‐ and P‐based anodes ever reported. The remarkable electrochemical performance is attributed to the sphalerite structure that allows fast ion and electron transport and the reversible Li‐storage mechanism involving intercalation and conversion reactions. Moreover, the cation‐disordered sphalerite structure is flexible to ionic substitutions, allowing extension to a family of Zn(Cu)Si2+xP3 solid solution anodes (x = 0, 2, 5, 10) with large capacity, high initial Coulombic efficiency, and tunable working potentials, representing attractive anode candidates for next‐generation, high‐performance, and low‐cost Li‐ion batteries.

The development of low-cost, high-performance anode materials for Li-ion batteries (LIBs) is imperative to meet the ever-increasing demands for advanced power sources. Here we report our findings on the design, synthesis, and characterization of a new cation-disordered ZnSiP2 anode. When tested in LIBs, the disordered phase of ZnSiP2 demonstrates faster reaction kinetics and higher energy efficiency than the cation-ordered phase of ZnSiP2. The superior performance is attributed to the greater electronic and ionic conductivity and better tolerance against volume variation during cycling, as confirmed by theoretical calculations and experimental measurements. Moreover, the cation-disordered ZnSiP2/C composite exhibits excellent cycle stability and superior rate capability. The performance surpasses all reported multi-phase anodes studied. Further, a number of the cation-disordered phases in the Zn(Cu)-Si-P family with a wide range of cation ratios show similar performance, achieving large specific capacities and high first-cycle coulombic efficiency while maintaining desirable working potentials for enhanced safety.

Finding low-cost and large-capacity anode materials to replace the commercially available graphite is an urgent need to meet the ever-increasing demand for high energy density Li-ion batteries (LIBs). Due to their suitable working potential, high theoretical capacity and low polarization, phosphides have attracted increasing interest as promising anode candidates for LIBs. However, phosphides suffer from large volume variation and low ionic and electronic conductivity, limiting the long-term cycling stability and rate capability. Herein, we report ZnP2/C derived from alfa-ZnP2 (tetragonal) and graphite as a highly reversible anode for LIBs. Alfa-ZnP2 (tetragonal) has been found to more easily form an amorphous composite with graphite with P-C bonds compared to Zn3P2. The amorphous structure could dramatically reduce the risk of fracture during cycling, profiting from an isotropic stress and the P-C bonds could enhance the Li-ion and electron transfer capability. Therefore, the ZnP2/C composite demonstrates significantly attractive performance in terms of reaction kinetics, energy efficiency and cycling stability with a specific capacity of 1270 mA h g-1 after 2730 cycles, making it superior to other Zn-P compounds and even other transition metal phosphide anodes. The highly reversible lithium storage capability of the ZnP2/C composite can be mainly attributed to the pseudocapacitive contribution. Additionally, the Li-ion full cell LiCoO2//ZnP2/C delivers 1200 mA h g-1 even after 200 cycles with an average working potential of 3.5 V, demonstrating its potential for application in next-generation Li-ion batteries. Broadly, this work would open an avenue for selecting appropriate phases and designing structural engineering with new chemical bonds to achieve ultralong cycling stability and ultrahigh rate performance.

Ge is considered a promising anode candidate for Li-ion batteries (LIBs); however, its practical applicability is hindered by the relatively slow Li-ion diffusion owing to the stiffness of the diamond-like structure. Inspired by little difference in electronegativity between Ge and P, we have designed a novel layered GeP anode for LIBs, which can be readily synthesized using a mechano-chemical method and a subsequent low-temperature annealing. In particular, GeP demonstrates the best performances among all Ge-based anode materials studied, attributed to its fast Li-ion diffusion compared to Ge counterpart and a unique Li-storage mechanism that involves intercalation, conversion, and alloying, as confirmed by XRD, TEM, XPS, and Raman spectroscopy. Specially, the initial layered crystal structure of GeP can be reconstructed during charging due to its low formation energy, thus offering remarkable reversibility during cycling. Further, this study implies that the formation energy of crystal structures could be an important parameter for strategic design of large-capacity anode materials for LIBs.

Ge is considered a promising anode candidate for Li-ion batteries (LIBs); however, its practical applicability is hindered by the relatively slow Li-ion diffusion owing to the stiffness of the diamond-like structure. Inspired by little difference in electronegativity between Ge and P, we have designed a novel layered GeP anode for LIBs, which can be readily synthesized using a mechano-chemical method and a subsequent low-temperature annealing. In particular, GeP demonstrates the best performances among all Ge-based anode materials studied, attributed to its fast Li-ion diffusion compared to Ge counterpart and a unique Li-storage mechanism that involves intercalation, conversion, and alloying, as confirmed by XRD, TEM, XPS, and Raman spectroscopy. Specially, the initial layered crystal structure of GeP can be reconstructed during charging due to its low formation energy, thus offering remarkable reversibility during cycling. Further, this study implies that the formation energy of crystal structures could be an important parameter for strategic design of large-capacity anode materials for LIBs.

Si‐based anodes with a stiff diamond structure usually suffer from sluggish lithiation/delithiation reaction due to low Li‐ion and electronic conductivity. Here, a novel ternary compound ZnSi2P3 with a cation‐disordered sphalerite structure, prepared by a facile mechanochemical method, is reported, demonstrating faster Li‐ion and electron transport and greater tolerance to volume change during cycling than the existing Si‐based anodes. A composite electrode consisting of ZnSi2P3 and carbon achieves a high initial Coulombic efficiency (92%) and excellent rate capability (950 mAh g−1 at 10 A g−1) while maintaining superior cycling stability (1955 mAh g−1 after 500 cycles at 300 mA g−1), surpassing the performance of most Si‐ and P‐based anodes ever reported. The remarkable electrochemical performance is attributed to the sphalerite structure that allows fast ion and electron transport and the reversible Li‐storage mechanism involving intercalation and conversion reactions. Moreover, the cation‐disordered sphalerite structure is flexible to ionic substitutions, allowing extension to a family of Zn(Cu)Si2+xP3 solid solution anodes (x = 0, 2, 5, 10) with large capacity, high initial Coulombic efficiency, and tunable working potentials, representing attractive anode candidates for next‐generation, high‐performance, and low‐cost Li‐ion batteries.

Si‐based anodes with a stiff diamond structure usually suffer from sluggish lithiation/delithiation reaction due to low Li‐ion and electronic conductivity. Here, a novel ternary compound ZnSi2P3 with a cation‐disordered sphalerite structure, prepared by a facile mechanochemical method, is reported, demonstrating faster Li‐ion and electron transport and greater tolerance to volume change during cycling than the existing Si‐based anodes. A composite electrode consisting of ZnSi2P3 and carbon achieves a high initial Coulombic efficiency (92%) and excellent rate capability (950 mAh g−1 at 10 A g−1) while maintaining superior cycling stability (1955 mAh g−1 after 500 cycles at 300 mA g−1), surpassing the performance of most Si‐ and P‐based anodes ever reported. The remarkable electrochemical performance is attributed to the sphalerite structure that allows fast ion and electron transport and the reversible Li‐storage mechanism involving intercalation and conversion reactions. Moreover, the cation‐disordered sphalerite structure is flexible to ionic substitutions, allowing extension to a family of Zn(Cu)Si2+xP3 solid solution anodes (x = 0, 2, 5, 10) with large capacity, high initial Coulombic efficiency, and tunable working potentials, representing attractive anode candidates for next‐generation, high‐performance, and low‐cost Li‐ion batteries.

Finding low-cost and large-capacity anode materials to replace the commercially available graphite is an urgent need to meet the ever-increasing demand for high energy density Li-ion batteries (LIBs). Due to their suitable working potential, high theoretical capacity and low polarization, phosphides have attracted increasing interest as promising anode candidates for LIBs. However, phosphides suffer from large volume variation and low ionic and electronic conductivity, limiting the long-term cycling stability and rate capability. Herein, we report ZnP2/C derived from alfa-ZnP2 (tetragonal) and graphite as a highly reversible anode for LIBs. Alfa-ZnP2 (tetragonal) has been found to more easily form an amorphous composite with graphite with P-C bonds compared to Zn3P2. The amorphous structure could dramatically reduce the risk of fracture during cycling, profiting from an isotropic stress and the P-C bonds could enhance the Li-ion and electron transfer capability. Therefore, the ZnP2/C composite demonstrates significantly attractive performance in terms of reaction kinetics, energy efficiency and cycling stability with a specific capacity of 1270 mA h g-1 after 2730 cycles, making it superior to other Zn-P compounds and even other transition metal phosphide anodes. The highly reversible lithium storage capability of the ZnP2/C composite can be mainly attributed to the pseudocapacitive contribution. Additionally, the Li-ion full cell LiCoO2//ZnP2/C delivers 1200 mA h g-1 even after 200 cycles with an average working potential of 3.5 V, demonstrating its potential for application in next-generation Li-ion batteries. Broadly, this work would open an avenue for selecting appropriate phases and designing structural engineering with new chemical bonds to achieve ultralong cycling stability and ultrahigh rate performance.

Finding low-cost and large-capacity anode materials to replace the commercially available graphite is an urgent need to meet the ever-increasing demand for high energy density Li-ion batteries (LIBs). Due to their suitable working potential, high theoretical capacity and low polarization, phosphides have attracted increasing interest as promising anode candidates for LIBs. However, phosphides suffer from large volume variation and low ionic and electronic conductivity, limiting the long-term cycling stability and rate capability. Herein, we report ZnP2/C derived from alfa-ZnP2 (tetragonal) and graphite as a highly reversible anode for LIBs. Alfa-ZnP2 (tetragonal) has been found to more easily form an amorphous composite with graphite with P-C bonds compared to Zn3P2. The amorphous structure could dramatically reduce the risk of fracture during cycling, profiting from an isotropic stress and the P-C bonds could enhance the Li-ion and electron transfer capability. Therefore, the ZnP2/C composite demonstrates significantly attractive performance in terms of reaction kinetics, energy efficiency and cycling stability with a specific capacity of 1270 mA h g-1 after 2730 cycles, making it superior to other Zn-P compounds and even other transition metal phosphide anodes. The highly reversible lithium storage capability of the ZnP2/C composite can be mainly attributed to the pseudocapacitive contribution. Additionally, the Li-ion full cell LiCoO2//ZnP2/C delivers 1200 mA h g-1 even after 200 cycles with an average working potential of 3.5 V, demonstrating its potential for application in next-generation Li-ion batteries. Broadly, this work would open an avenue for selecting appropriate phases and designing structural engineering with new chemical bonds to achieve ultralong cycling stability and ultrahigh rate performance.

Ge is considered a promising anode candidate for Li-ion batteries (LIBs); however, its practical applicability is hindered by the relatively slow Li-ion diffusion owing to the stiffness of the diamond-like structure. Inspired by little difference in electronegativity between Ge and P, we have designed a novel layered GeP anode for LIBs, which can be readily synthesized using a mechano-chemical method and a subsequent low-temperature annealing. In particular, GeP demonstrates the best performances among all Ge-based anode materials studied, attributed to its fast Li-ion diffusion compared to Ge counterpart and a unique Li-storage mechanism that involves intercalation, conversion, and alloying, as confirmed by XRD, TEM, XPS, and Raman spectroscopy. Specially, the initial layered crystal structure of GeP can be reconstructed during charging due to its low formation energy, thus offering remarkable reversibility during cycling. Further, this study implies that the formation energy of crystal structures could be an important parameter for strategic design of large-capacity anode materials for LIBs.

The development of low-cost, high-performance anode materials for Li-ion batteries (LIBs) is imperative to meet the ever-increasing demands for advanced power sources. Here we report our findings on the design, synthesis, and characterization of a new cation-disordered ZnSiP2 anode. When tested in LIBs, the disordered phase of ZnSiP2 demonstrates faster reaction kinetics and higher energy efficiency than the cation-ordered phase of ZnSiP2. The superior performance is attributed to the greater electronic and ionic conductivity and better tolerance against volume variation during cycling, as confirmed by theoretical calculations and experimental measurements. Moreover, the cation-disordered ZnSiP2/C composite exhibits excellent cycle stability and superior rate capability. The performance surpasses all reported multi-phase anodes studied. Further, a number of the cation-disordered phases in the Zn(Cu)-Si-P family with a wide range of cation ratios show similar performance, achieving large specific capacities and high first-cycle coulombic efficiency while maintaining desirable working potentials for enhanced safety.

The development of low-cost, high-performance anode materials for Li-ion batteries (LIBs) is imperative to meet the ever-increasing demands for advanced power sources. Here we report our findings on the design, synthesis, and characterization of a new cation-disordered ZnSiP2 anode. When tested in LIBs, the disordered phase of ZnSiP2 demonstrates faster reaction kinetics and higher energy efficiency than the cation-ordered phase of ZnSiP2. The superior performance is attributed to the greater electronic and ionic conductivity and better tolerance against volume variation during cycling, as confirmed by theoretical calculations and experimental measurements. Moreover, the cation-disordered ZnSiP2/C composite exhibits excellent cycle stability and superior rate capability. The performance surpasses all reported multi-phase anodes studied. Further, a number of the cation-disordered phases in the Zn(Cu)-Si-P family with a wide range of cation ratios show similar performance, achieving large specific capacities and high first-cycle coulombic efficiency while maintaining desirable working potentials for enhanced safety.

Flexible V–O–C composite nanofibers were fabricated from solution precursors via electrospinning and were investigated as free-standing and additive-free film electrodes for supercapacitors. Specifically, composite nanofibers (V0, V5, V10 and V20) with different vanadyl acetylacetonate (VO(acac)2) contents of 0, 5, 10 and 20 wt% with respect to polyacrylonitrile (PAN) were prepared. The composite nanofibers were comparatively studied using XRD, Raman spectroscopy, XPS, N2 adsorption–desorption, FE-SEM, TEM and S-TEM. The vanadium element was found to be well-dispersed in the carbon nanofibers, free from the formation of an aggregated crystalline phase, even in the case of V20. A specific surface area of 587.9 m2 g-1 was reached for V10 after calcination, which is approximately twice that of the vanadium-free carbon nanofibers (V0, 300.9 m2 g-1). To perform as an electrode for supercapacitors in an aqueous electrolyte, the V10 film delivered a specific capacitance of 463 F g-1 at 1 A g-1. V10 was also able to retain a specific capacitance of 380 F g-1, even at a current density of 10 A g-1. Additionally, very stable cycling stability was achieved, maintaining an outstanding specific capacitance of 400 F g-1 at 5 A g-1 after charge–discharge cycling 5000 times. Thus, V–O–C composite nanofibers are highly attractive electrode materials for flexible, high-power, thin film energy storage devices and applications.