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Application of transition metal elements in catalysis has become a research hotspot in recent years. Here, two kinds of transition metal-centered HER electrocatalyst of Co(Ⅱ)TPP-based coordination compounds and Fe(Ⅲ)TPP-based coordination compounds are reported. Both of coordination compounds show high photocurrent response and excellent hydrogen evolution activity. The most attraction is that FeTPP-OA/PVP58, FeTPP-PTA/PVP58, FeTPP-OA/PVP1300 and FeTPP-PTA/PVP1300 possess a special surface with a big spine-like cross which is different to the regular pyramid morphology of the other coordination compounds, and these coordination compounds display superior HER performance compare to the other samples. Especially, FeTPP-OA/PVP58 exhibits a low overpotential of 83 mV at the current density of 10 mA cm−2 and an ultralow Tafel slope of 39 mV dec−1 which is close to the Pt/C (29 mV dec−1). The low charge transfer resistance of 14.4 Ω and high photocurrent of 3 μA under visible light illumination also reveal the outstanding photoelectrochemical property of FeTPP-OA/PVP58. This work provides a novel insight into the design of transition metal-centered HER electrocatalyst with high-efficiency electrocatalytic activity and low cost.

Hydrogen production from electrocatalytic water splitting has aroused extensive attention in many fields recently. Fabrication of low-cost and high-efficiency electrocatalysts are still an urgent and challenging work. Porphyrins as visible-light photosensitizers have been extensively utilized in visible-light photocatalysts and photoelectronic materials. So, fabrication of novel porphyrin-based complexes will be benefited for high-efficiency hydrogen evolution and photoelectric response. Here a series of zirconium porphyrin-based coordination complexes were successfully fabricated via a facile two-step strategy. Due to the unique long chain-like structure and low charge-transfer resistance, the zirconium porphyrin-based coordination complexes displayed excellent electrocatalytic performance for hydrogen evolution reaction. The ZrTPP-PTA-1 showed a low overpotential of 60 mV at the current density 10 mA cm−2 and a Tafel slope of 87 mV dec−1 with an ultralow electron transfer resistance of 17.5 Ω. In addition, a quick photocurrent response occurred for these coordination complexes with a visible-light illumination. The photocurrent of the ZrTPP-OA-2 rised up to 2.5 μA under visible-light irradiation. With this pleasant result, these zirconium porphyrin-based coordination complexes have a great potential to become available alternative of current noble electrocatalysts for photoelectric application.

The ultrasensitive detection of fibroin in unearthed silk relics has great significance for investigating the origin and transmission of silk. In this study, an anti-fibroin monoclonal antibody was successfully prepared through animal immunization. Next, a label-free electrochemical immunosensor was fabricated using layer-by-layer self-assembly technology, and an indirect enzyme-linked immunosorbent assay (ELISA) was proposed. The two methods exhibited excellent sensitivity and specificity in the detection of silk fibroin, while the immunosensor showed a wider quantitative detection range (0.1–100 ng mL−1) and a lower detection limit (0.051 ng mL−1) than ELISA (10–100 ng mL−1 and 8.71 ng mL−1). Furthermore, the performance of the immunosensor was superior in archaeological sample detection. Taking advantage of the well-prepared monoclonal antibody, the two proposed immunological assays demonstrate tremendous potential for the ultrasensitive detection of silk fibroin, which can make great contributions to exploring the origin and transmission routes of ancient silks.