Study On Non-Precious Metal Electrochemical Catalyst Derived From Bio-Mass

It was well known that N-doped carbon nanomaterials usually have polarized elec-tron cloud distribution,excellent electron transport properties,high specific surface area and stable structure.Metal/Nitrogen doped carbon materials(M/N-C)was defined as carbon nanomaterials which doped by non-noble metal elements such as Fe,Co,Cu,Ni and non-metallic elements N.It was no doubt that M/N-C preserves the quality of the carbon nanomaterials themselves.By changing the precursor/ligand structure,the electronic structure of C atoms around M and N could be controlled,which enhanced the related properties of carbon nanomaterials.These were the foundations for which M/N-C can replace precious metals in the field of energy conversion/molecular trans-formation.In the new period,China pays great attention to the prevention and control of pollution.Only eliminate toxic and harmful substances including raw mateirals,pro-cessing and production to the goods shelves,the high pollution caused by chemical industry can changed into the real green chemical production through-train.Biomass is a kind of green renewable waste,if treated non-properly,the vicous cycle of“produc-tion-waste-pollution-production”will formed.Obviously,changing biomass into M/N-C can be defined as“changing waste into treasure”.At present,there are a large number of reports on the preparation of N-doped carbon materials from biomass.However,it is noteworthy that most of them care concentrated in the 4e~-ORR to be applied to the cathode catalyst for fuel cell.But,the possibility of industrial application of hydrogen peroxide produced by 2e~-ORR process is ignored.More importantly,hydrogen peroxide as an important chemical raw material,not only the existing production methods are lack of secrutiy,but also the environment is not friendly.Therefore,the purpose of this thesis is to prepare N-doped carbon nanomaterials through biomass based on the simple preparation system and explore the best preparation scheme of catalyst for electrochem-ical catalytic hydrogen peroxide production.By controlling the addition of non noble metals,we can control the physical and chemical structure of N-doped non noble metal materials,and explore the factors that influence the selectivity of electrocatalytic oxy-gen reduction.By adjusting the structure of biomass precursors,we can control the properties of N-doped carbon materials and develop it in other energy conversion fields,such as the prossibility of CO2 reduction.The research content of this paper include the following two parts:1.Pomelo peel was used as precursor to prepare Fe/N-doped carbon materials by high temperature pyrolysis.The advantage of this method included no need of templates,multiple processes,and toxic and harmful substances,making it environmental-friendly.N-doped carbon materials with excellent production of hydrogen peroxide per-formance have successfully prepared thourgh this method.Through the addition of Fe elements,the number of defects which means the graphitation of carbon and the content of pyridine nitrogen were controlled.So that,the influence between the selectivity of ORR and the number of defects was explored.The experimental results showed that the number of defects is and important factor affecting the selecitivity of ORR.2.Considering the soybean milk changed into tofu/tofu gel can be defined as an sol-gel transformation process,it means we can achieve precise regulation of the structure of biomass precursors.What'more,we can also explore the relationship between N-doped carbon materials and the structure of biomass precursors.