Nonprecious group metal (NPGM)‐based single atom catalysts (SACs) hold a great potential in electrocatalysis and dopant engineering has been extensively exploited to boost their catalytic activity, while the coordination environment of dopant, which also significantly affects the electronic structure of SACs, and consequently their electrocatalytic performance, have been largely ignored. Here, by adopting a precursor modulation strategy, the authors successfully synthesize single cobalt atom catalysts embedded in nitrogen‐doped carbon, Co–N/C, with similar overall Co and N concentrations but different N types, that is, pyridinic N (NP), graphitic N (NG), and pyrrolic N (NPY). Co–N/C with the Co–N4 moieties coordinated with NG displays far superior activity for oxygen reduction (ORR) and evolution reactions, and superior activity and stability in both zinc–air batteries and proton exchange membrane fuel cells. Density functional theory calculation indicates that coordinated N species in particular NG functions as electron donors to the Co core of Co–N4 active sites, leading to the downshift of d‐band center of Co–N4 and weakening the binding energies of the intermediates on Co–N4 sites, thus, significantly promoting catalytic kinetics and thermodynamics for ORR in a full pH range condition.

This study prepares a new form of cellulose/graphene composite (CGC) by mixing dissolved cellulose with graphene oxide and reducing it with hydrazine hydrate. The composite particles achieve higher adsorption levels than five other sorbents (graphite carbons, primary secondary amine (PSA), graphite carbon black (GCB), cellulose, and graphene) for six triazine pesticides. The adsorption process only requires adding 30 mg of CGC for 10 mL of solution of triazine pesticides. The mixture is hand-shaken five times at pH 9. The equilibrium adsorption isotherm reveals that the Langmuir model describes the adsorption process better. Thermodynamic parameters indicate that adsorption is spontaneous, favorable, and endothermic in nature. Furthermore, the CGC is very stable and can easily be recycled using a simple organic solvent. The adsorption efficiency of the CGC is still over 85% after six times of recycling.

Environmental issues such as the wastewater have influenced each aspect of our lives. Coupling the existing remediation solutions with exploring new functional carbon nanomaterials (e.g., carbon nanotubes, graphene oxide, graphene) by various perspectives shall open up a new venue to understand the environmental issues, phenomenon and find out the ways to get along with the nature. This review makes an attempt to provide an overview of potential environmental remediation solutions to the diverse challenges happening by using low-dimensional carbon nanomaterials and their composites as adsorbents, catalysts or catalysts support towards for the social sustainability.

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