Electro-oxidation of 5-hydroxymethylfurfural(HMFOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of HMF,an ...Electro-oxidation of 5-hydroxymethylfurfural(HMFOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of HMF,an in-depth understanding of the electrocatalytic behavior of HMFOR has rarely been investigated.Herein,the electrocatalytic mechanism of HMFOR on nickel nitride(Ni3 N)is elucidated by operando X-ray absorption spectroscopy(XAS),in situ Raman,quasi in situ X-ray photoelectron spectroscopy(XPS),and operando electrochemical impedance spectroscopy(EIS),respectively.The activity origin is proved to be Ni^(2+δ)N(OH)ads generated by the adsorbed hydroxyl group.Moreover,HMFOR on Ni3 N relates to a two-step reaction:Initially,the applied potential drives Ni atoms to lose electrons and adsorb OH-after 1.35 VRHE,giving rise to Ni^(2+δ)N(OH)ads with the electrophilic oxygen;then Ni^(2+δ)N(OH)ads seizes protons and electrons from HMF and leaves as H_(2) O spontaneously.Furthermore,the high electrolyte alkalinity favors the HMFOR process due to the increased active species(Ni^(2+δ)N(OH)ads)and the enhanced adsorption of HMF on the Ni3 N surface.This work could provide an in-depth understanding of the electrocatalytic mechanism of HMFOR on Ni3 N and demonstrate the alkalinity effect of the electrolyte on the electrocatalytic performance of HMFOR.展开更多
Degradation reaction of doxycycline or methacycline was carried out in KOH solution and intense fluorescence was obtained.A degradation mechanism of doxycycline or methacycline was suggested.
Dyeing of PET materials by traditional methods presents several problems.Plasma technology has received enormous attention as a solution for the environmental problems related with textile surface modifications,and th...Dyeing of PET materials by traditional methods presents several problems.Plasma technology has received enormous attention as a solution for the environmental problems related with textile surface modifications,and there has been a rapid development and commercialization of plasma technology over the past decade.In this work,the synergistic effect of atmospheric pressure plasma on alkaline etching and deep coloring of dyeing properties on polyethylene terephthalate(PET)fabrics and films was investigated.The topographical changes of the PET surface were investigated by atomic force microscopy(AFM)images,which revealed a smooth surface morphology of the untreated sample whereas a high surface roughness for the plasma and/or alkaline treated samples.The effects of atmospheric pressure plasma on alkaline etching of the structure and properties of PET were investigated by means of differential scanning calorimetry(DSC),the main objective of performing DSC was to investigate the effect of the plasma pre-treatment on the T_g and T_m.Using a tensile strength tester YG065 H and following a standard procedure the maximum force and elongation at maximum force of PET materials was investigated.Oxygen and argon plasma pre-treatment was found to increase the PET fabric weight loss rate.The color strength of PET fabrics was increased by various plasma pre-treatment times.The penetration of plasma and alkaline reactive species deep into the PET structure results in better dyeability and leaves a significant effect on the K/S values of the plasma pre-treated PET.It indicated that plasma pre-treatment has a great synergistic effect with the alkaline treatment of PET.展开更多
基金supported by the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(Grant No.:21902047)+1 种基金the Provincial Natural Science Foundation of Hunan(2020JJ5045)the Fundamental Research Funds for the Central Universities(Grant No.531118010127)。
文摘Electro-oxidation of 5-hydroxymethylfurfural(HMFOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of HMF,an in-depth understanding of the electrocatalytic behavior of HMFOR has rarely been investigated.Herein,the electrocatalytic mechanism of HMFOR on nickel nitride(Ni3 N)is elucidated by operando X-ray absorption spectroscopy(XAS),in situ Raman,quasi in situ X-ray photoelectron spectroscopy(XPS),and operando electrochemical impedance spectroscopy(EIS),respectively.The activity origin is proved to be Ni^(2+δ)N(OH)ads generated by the adsorbed hydroxyl group.Moreover,HMFOR on Ni3 N relates to a two-step reaction:Initially,the applied potential drives Ni atoms to lose electrons and adsorb OH-after 1.35 VRHE,giving rise to Ni^(2+δ)N(OH)ads with the electrophilic oxygen;then Ni^(2+δ)N(OH)ads seizes protons and electrons from HMF and leaves as H_(2) O spontaneously.Furthermore,the high electrolyte alkalinity favors the HMFOR process due to the increased active species(Ni^(2+δ)N(OH)ads)and the enhanced adsorption of HMF on the Ni3 N surface.This work could provide an in-depth understanding of the electrocatalytic mechanism of HMFOR on Ni3 N and demonstrate the alkalinity effect of the electrolyte on the electrocatalytic performance of HMFOR.
文摘Degradation reaction of doxycycline or methacycline was carried out in KOH solution and intense fluorescence was obtained.A degradation mechanism of doxycycline or methacycline was suggested.
基金partially supported by the National Natural Science Foundation of China Contract 11375042
文摘Dyeing of PET materials by traditional methods presents several problems.Plasma technology has received enormous attention as a solution for the environmental problems related with textile surface modifications,and there has been a rapid development and commercialization of plasma technology over the past decade.In this work,the synergistic effect of atmospheric pressure plasma on alkaline etching and deep coloring of dyeing properties on polyethylene terephthalate(PET)fabrics and films was investigated.The topographical changes of the PET surface were investigated by atomic force microscopy(AFM)images,which revealed a smooth surface morphology of the untreated sample whereas a high surface roughness for the plasma and/or alkaline treated samples.The effects of atmospheric pressure plasma on alkaline etching of the structure and properties of PET were investigated by means of differential scanning calorimetry(DSC),the main objective of performing DSC was to investigate the effect of the plasma pre-treatment on the T_g and T_m.Using a tensile strength tester YG065 H and following a standard procedure the maximum force and elongation at maximum force of PET materials was investigated.Oxygen and argon plasma pre-treatment was found to increase the PET fabric weight loss rate.The color strength of PET fabrics was increased by various plasma pre-treatment times.The penetration of plasma and alkaline reactive species deep into the PET structure results in better dyeability and leaves a significant effect on the K/S values of the plasma pre-treated PET.It indicated that plasma pre-treatment has a great synergistic effect with the alkaline treatment of PET.