Query: Phosphorus doping graphene

title: Inhibited combustion of graphene paper by in situ phosphorus doping and its application for fire early warning sensor
abstract: Although traditional fire detectors are widely used in many occasions, they still show some limitations, such as slow fire response and poor resistance to severe conditions. Thus, it is urgent to design and exploit early fire warning device with ultrafast response and flame retardant ability to provide timely and fast alarm. Herein, graphene oxide paper functionalized with phosphoric acid (GO PA) is fabricated by a facile and environmentally friendly water evaporation induced self assembly approach. Based on the flame induced electrical resistance transformation characteristic of GO PA, a fire warning detector is designed to reliably monitor early fire. Fire alarm can be triggered within 0.5 s when GO PA samples are attacked by fire. The GO PA composite paper is more sensitive than GO based fire sensors reported in the literature. Phosphorus atoms are in situ doped into graphene structure during flame exposure. Combustion reaction of GO is significantly retarded by the incorporated PA, thus fire duration time of GO is greatly improved. This work paves a new way to improve fire detection performance of GO based sensors. This work provides a guide for the development of advanced fire detection and early warning sensors to provide reliable and continuous alarm signals.

title: Tailoring Electronic and Magnetic Properties of Graphene by Phosphorus Doping.
abstract: The electronic and magnetic properties of graphene can be modulated by doping it with other elements, especially those with a different number of valence electrons. In this article, we first provide a three dimensional reconstruction of the atomic structure of a phosphorus substitution in graphene by using aberration corrected scanning transmission electron microscopy. Turning then to theoretical calculations based on density functional theory (DFT) we show that that doping phosphorus in various bonding configurations can induce magnetism in graphene. Our simulations reveal that the electronic and magnetic properties of P doped (Gr P) and/or phosphono functionalized graphene (Gr PO3H2) can be controlled by both the phosphorus concentration and configurations, ultimately leading to ferromagnetic (FM) and/or antiferromagnetic (AFM) features with the transition temperature up to room temperature. We also calculate core level binding energies of variously bonded P to facilitate X ray photoelectron spectroscopy based identification of its chemical form present in P doped graphene based structures. These results may enable the design of graphene based organic magnets with tailored properties for future magnetic or spintronic applications.

title: Phosphorus doping and addition of V2O5 into Pt/graphene resulting in highly enhanced electro photo synergistic catalysis for oxygen reduction and hydrogen evolution reactions
abstract: Both the introduction of photo responsive metal oxide and the heteroatoms doping into Pt based catalysts may be a promising strategy to enhance its catalytic properties. In this paper, one pot solid phase synthesis was employed to synthesize Pt (P) V2O5/GNs catalyst, and it is shown that the addition of photo responsive V2O5 and the doping of P are successfully achieved. Electrochemical measurements show that the Pt (P) V2O5/GNs exhibits attractive bi functional electrocatalytic property for ORR and HER, in comparison with the commercial PtRu/C JM catalyst. More importantly, Pt (P) V2O5/GNs presents much better electro photo synergistic catalysis both for ORR and HER due to its excellent photo responsive properties of V species in Pt (P) V2O5/GNs, resulting in drastically enhanced catalytic activity and stability under the simulated sunlight irradiation.

title: Surface engineering of phosphorus low doping palladium nanoalloys anchored on the three dimensional nitrogen doped graphene for enhancing ethanol electroxidation
abstract: The development of superior supporting materials supported surface engineered metallic nanocrystals is desired and necessary for promoting the electrocatalytic performance of ethanol electroxidation. Additionally, the facile and mild synthetic strategy for advanced electrocatalyst is also urgently needed. Herein, a new catalyst comprising of phosphorus low doping palladium nanoalloys uniformly anchored on the three dimensional nitrogen doped graphene (denoted as Pd P/3DNGS) is synthesized by a facile one pot surfactant free hydrothermal method. Notably, the optimized Pd P/3DNGS 2 displays an inspiring enhanced electrochemical behavior to ethanol oxidation in terms of catalytic activity, accelerated kinetics, improved long term stability and boosted anti poisoning capability, which may be derived from the unique architecture of 3DNGS and the providential electron effect between Pd and P. This work provides a new access for rational design of nano electrocatalysts.

title: Enhancing thermal oxidation and fire resistance of reduced graphene oxide by phosphorus and nitrogen co doping: Mechanism and kinetic analysis
abstract: The use of reduced graphene oxide (rGO) in high temperature oxidization (HTO) environment, is limited by its poor thermal oxidation and fire resistance. In this study phosphorus and nitrogen co doped reduced graphene oxide (PN rGO) with high oxidation and fire resistance was prepared by hydrothermal and microwave treatment and its thermal oxidation decomposition kinetics and mechanisms were analyzed. Concisely, PN rGO presents an increment of 162 degC in the decomposition temperature relative to undoped rGO (WrGO) and excellent fire resistance with only a ~20% mass loss after burning. Thermal oxidation degradation kinetics reveals that WrGO shows continuously increasing activation energy (E) within a range of 119.7 182.9 kJ/mol, while PN rGO exhibits almost constant E of ~171.8 kJ/mol during main degradation stage. Moreover, the improved E at initial stage by phosphorus/nitrogen doping, combining with the char analysis, suggested that the introduction of strong chemical bonds replacing the reactive oxygen containing groups was the key to preventing the oxidation of rGO. As one of the main properties, the electrical conductivity of PN rGO is well kept after HTO treatment. This work demonstrates that a doping strategy can effectively expand the application of graphene based devices in HTO environment.

title: Surface modulated hierarchical graphene film via sulfur and phosphorus dual doping for high performance flexible supercapacitors
abstract: Graphene surface modification by heteroatom incorporation is an attractive strategy to construct flexible electrochemical capacitors. Herein, the steam assistant heteroatoms of sulfur and phosphorus dual doped graphene film (s SPG) is fabricated via an ice template and thermal activation approach and they demonstrate an excellent pseudocapacitive behavior in flexible electrochemical capacitors. As probed by various microscopic and spectroscopic analysis, well maintained porosity structure is formed during the freeze drying and steam activation treatment; the increased surface roughness is ascribed to heteroatoms doping by the formation of S and P containing functional groups as electrochemical active sites. A flexible device integrated by porous s SPG film shows high pseudocapacitive behavior with high specific capacitance (169 F/g) rate capability (91.7% and cyclic stability (92.5% Even at the bend angle of 120deg, no obvious change of specific capacitance is found indicating a good flexibility of s SPG devices; the current study shows that s SPG is a very promising electrode to realize the practical applications of all solid flexible supercapacitors.

title: Defect Rich Graphene Architecture Induced by Nitrogen and Phosphorus Dual Doping for High Performance Supercapacitors

title: Cu Phosphorus Eutectic Solid Solution for Growth of Multilayer Graphene with Widely Tunable Doping

title: Boron/phosphorus doping for retarding the oxidation of reduced graphene oxide
abstract: B, N and P, N doped reduced graphene oxide (RGO) are prepared through high temperature annealing method using boric acid and phosphoric acid as the B and P sources, respectively. The synthesized RGO and dual doped RGO are well characterized by Fourier transform infrared spectroscopy, X ray diffraction, Raman spectroscopy, X ray photoelectron spectroscopy and transmission electron microscopy. The heteroatoms are found to be introduced into the graphene structure. The low level of doping (approximately 1.10 at% exhibits significant improvement in thermal oxidative stability of RGO. In comparison with neat RGO, the temperature at maximum weight loss rate of B RGO and P RGO increase by as much as 52 degC and 130 degC, respectively. The mechanism for retarding RGO oxidation by B/P doping is clearly proposed. More stable bond configurations are formed in the B/P doped RGO. The doped B and P atoms reduce the reactivity of carbon active sites and inhibit the carbon gasification. This work will provide an understanding of thermal oxidative stability of heteroatoms doped RGO, and offer a strategy for fabricating graphene with elevated temperature applications.

title: Tuning the Double Layer of Graphene Oxide through Phosphorus Doping for Enhanced Supercapacitance
abstract: The electrochemical double layer plays a fundamental role in energy storage applications. Control of the distribution of ions in the double layer at the atomistic scale offers routes to enhanced material functionality and device performance. Here we demonstrate how the addition of an element from the third row of the periodic table, phosphorus, to graphene oxide increases the measured capacitance and present density functional theory calculations that relate the enhanced charge storage to structural changes of the electrochemical double layer. Our results point to how rational design of materials at the atomistic scale can lead to improvements in their performance for energy storage.