Poly tetrafluoroethylene

The silkworm strain used in the experiment was Bombyx mori (871 × 872), sourced from the Chongqing Sericulture Science and Technology Research Institute (Chongqing, China). Ammonium molybdate tetrahydrate (AMT) was purchased from Shanghai Darui Fine Chemical Co., Ltd. (Shanghai, China); sodium chloride was purchased from Shanghai Aladdin Bio-Chem Technology Co., Ltd. (Shanghai, China); nitric and perchloric acids were purchased from Beijing Institute of Chemical Reagents (Beijing, China); sodium carbonate and ethanol were purchased from Chongqing Chuandong Chemical Co., Ltd. (Chongqing, China); potassium bromide was purchased from Sangon Biotech Co., Ltd. (Shanghai, China); hematoxylin and eosin (H&E) staining kits were purchased from Nanchang Yulu Experimental Equipment Co., Ltd. (Nanchang, China); dimethylbenzene and poly (tetrafluoroethylene) were purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China); Super P was purchased from Canrd New Energy Technology Co., Ltd. (Guangzhou, China); and foam Ni was purchased from Taiyuan Lizhiyuan Co., Ltd. (Shanxi, China). All chemicals were of analytical grade and used without further purification. The deionized (DI) water used in this work was produced using a Milli-Q Direct-8 purification system (resistivity >18 MΩ cm, Millipore Inc., France) onsite.

Co(NO₃)₂·6H₂O (AR), polytetrafluoroethylene (60 wt%), acetylene black (99%) and dimethyl sulfoxide (AR) were purchased from Macklin. Acrylamide (99%), N,N′-methylenebisacrylamide (99%), potassium persulfate (99.99%) were purchased from Aladdin. Methanol (AR), isopropanol (AR), potassium hydroxide (AR), hydrochloric acid (AR), and Zn(Ac)₂·2H₂O (AR) were purchased from Sinopharm Chemical Reagent Co., Ltd, China. Zn plate was purchased from Shanghai Maikelong Co., Ltd. Commercial Pt/C (20 wt%), Pt/C + RuO₂ (30 wt%) electrocatalyst and Nafion solution (5 wt%, D520) were purchased from Shanghai Hesen Electric Co., Ltd. All chemicals were from commercial sources and used without further purification. Water-proof breathable membrane and Ni foam were purchased from Changsha spring new energy technology Co., Ltd. Graphene oxide aqueous solution and g-C₃N₄ nanosheets are synthesized by the method we previously reported³⁴ . N₂ (99.99%) and O₂ (99.99%) were purchased from Changsha Xinxiang Gas Chemical Co., Ltd. Milli-Q water (18.2 MΩ) was obtained from milli-Q system (UPT).