Environmentally‐friendly carbon nanomaterials for photocatalytic hydrogen production

Currently,the energy crisis is the crucial problem faced by the world,and photocatalytic hydrogen(H_(2))production is recognized with a chance to be a standout amongst those guaranteeing results to this issue.For a long time,photocatalytic H_(2) production has mainly relied on the noble metal cata‐lysts.However,the limitations of noble metals themselves,such as scarcity and high cost,have se‐verely restricted their large‐scale application.Therefore,it is urgent to seek a cheaper,more effi‐cient,and stable catalyst for photocatalytic H_(2) production.Fortunately,the emergence of carbon nanostructured materials(CNMs)has brought dawn.Its excellent structure and semiconductor performance can effectively participate in photocatalytic H_(2) production.CNMs have developed rap‐idly since they appeared in the field of photocatalytic water splitting.Therefore,it is necessary to summarize the latest progress of CNMs promptly for further development.This review introduced the CNMs,including carbon dots,fullerenes,carbon nanotubes,graphene,and graphdiyne,which is a powerful assistant in photocatalytic H_(2) production.CNMs can provide abundant adsorption and active sites,charge separation and transport channels,photocatalysts,co‐catalysts and photosensi‐tizers.Then,this review has introduced the strategy for enhancing CNMs in photocatalytic H_(2) pro‐duction based on recent research.Finally,the challenge faced by CNMs in photocatalytic H_(2) produc‐tion has prospected.

Adsorption-desorption Characteristics and Thermodynamics of Quinclorac on Minerals

Adsorption-desorption characteristics of quinclorac on montmorillonite, attapulgite and goethite were investigated by the batch equilibrium techniques. The sorption mechanisms of minerals were discussed based on sorption thermodynamics. The results showed that the adsorption of quinclorac on the 3 minerals was included in both rapid stage and slow equilibrium stage. The adsorption kinetics consisted with the pseudo-second-order equation, the particle diffusion equation, and elovich equations, and among them, fitting from the pseudo-second-order was the best. In addition, it could be seen from the nonzero constant C in the particle diffusion equation that the rate of particle diffusion was not a sole factor. The isotherm adsorption-desorption of quinclorac on the 3 clay minerals all fitted Linear and Freundlich equation very well. The adsorption capacities of minerals for quinclorac followed the order of goethite〉montmorillonite〉attapulgite, The desorption of quinclorac presented obvious hysteresis phenomenon on minerals. The study on thermodynamic behavior indicated that the sorption processes of quinclorec onto minerals were spontaneous, and the sorption spontaneity was strengthened with the temperature increasing.

Unveiling the synergistic effect of internal Fe single atoms and introduced Fe_(3)C in Enteromorpha derived biochar with enhanced peroxymonosulfate activation property towards nitenpyram removal

This work demonstrated that Enteromorpha biochar with introduced iron(SFB900-3)could activate peroxymonosulfate(PMS)efficiently for NTP remediation.It removed 83.9%-95.1%of NTP in 60 min under a wide pH range from 3.15 to 8.95.Density functional theory(DFT)calculations revealed the synergistic relationship between internal Fe single atoms and introduced Fe compounds—Fe_(3)C.The adsorption capacity of SFB900-3 for persulfate improved from−0.953 eV to−4.214 eV,and the Bader charge analysis showed that Fe atoms as active sites(0.658 e)enhanced the adsorption capacity more than carbon(0.050 e).Moreover,the energy barrier for PMS dissociation reduced from 0.072 eV to−5.372 eV due to the longer length of O-O bond under the synergistic effect of Fe single atom and Fe_(3)C which increased from 1.467Åto 3.890ÅThe quenching experiment confirmed that ^(1)O_(2) was the main active substance in NTP degradation and its contribution rate was 88.2%,which was further verified by EPR detection.The effect factor experiments proved that the SFB900-3/PMS system had stable and efficient activity for NTP removal,which remained at 73.6%removal rate after three rounds of tests.This work provided novel guidance for constructing efficient and stable biochar-based materials for organic pollutant remediation.