NiO_(x)/BiVO_(4)/C/Cu_(2)O纳米线光阴极的制备及其在污泥制氢系统中的应用

Fabrication of NiO_(x)/BiVO_(4)/C/Cu_(2)O nanowires photocathode and its application in sludge hydrogen production system

微生物光电化学池(BPEC)系统是一种将生物阳极与光阴极耦合,利用太阳能和生物能进行产氢的新型绿色技术。以较廉价的Cu_(2)O纳米线为基底,通过C层与稳定的BiVO_(4)构建异质结,添加助催化剂合成NiO_(x)/BiVO_(4)/C/Cu_(2)O纳米线光阴极;以剩余污泥为底物,构建了BPEC系统及微生物燃料电池(MFC)与BPEC耦合(MFC-BPEC)系统,研究其污泥减量及产氢效果。结果表明,制备的NiO_(x)/BiVO_(4)/C/Cu_(2)O纳米线光阴极在-0.8 V(vs Ag/AgCl)偏压下达到了-5.20 mA/cm^(2)的光电流密度。构建的BPEC系统和MFC-BPEC系统可利用污泥中的化学需氧量(COD)、悬浮物(SS)、蛋白质及多糖为底物产氢,与BPEC系统相比,串联两个MFC的MFC-BPEC(DMFC-BPEC)系统可以显著提高污泥降解速率和氢气产率(分别为377.75 mg/(L·h)和15.50 mg/g)。研究为利用太阳能驱动的微生物电化学系统实现污泥减量化与资源化提供了理论依据。

The bio-photo-electro-chemical(BPEC)system is a new green technology that couples a biological anode with a photocathode to produce hydrogen using solar energy and bioenergy.In this paper,NiO_(x)/BiVO_(4)/C/Cu_(2)O nanowires(NWs)photocathode were synthesized by adding NiO_(x) co-catalyst to the heterojunctions constructed by cheaper Cu_(2)O NWs substrate and stable BiVO_(4) through a C layer.A BPEC system and microbial fuel cell(MFC)and BPEC coupling(MFC-BPEC)system were constructed using the residual sludge as the substrate.The sludge reduction and hydrogen production performance were studied.The results showed that a photocurrent of-5.20 mA/cm^(2)was achieved under a bias voltage of-0.8 V(vs Ag/AgCl)for the NiO_(x)/BiVO_(4)/C/Cu_(2)O NWs composite photocathode.The constructed BPEC and MFC-BPEC systems could produce hydrogen using COD,SS,proteins and polysaccharides in sludge.Compared with BPEC system,the DMFC-BPEC system combining with two MFC s could significantly improve the sludge degradation rate and hydrogen yield(377.75 mg/(L·h)and 15.50 mg/g,respectively).This research provides a theoretical basis for the use of solar-driven microbial electrochemical systems to achieve sludge reduction and resource utilization.