In recent years, nanozymes have attracted particular interest and attention as catalysts because of their high catalytic efficiency and stability compared with natural enzymes, whereas how to use simple methods to further improve the catalytic activity of nanozymes is still challenging. In this work, we report a trimetallic metal–organic framework (MOF) based on Fe, Co and Ni, which was prepared by replacing partial original Fe nodes of the Fe-MOF with Co and Ni nodes. The obtained FeCoNi-MOF shows both oxidase-like activity and peroxidase-like activity. FeCoNi-MOF can not only oxidize the chromogenic substrate 3,3,5,5-tetramethylbenzidine (TMB) to its blue oxidation product oxTMB directly, but also catalyze the activation of H₂O₂ to oxidize the TMB. Compared with corresponding monometallic/bimetallic MOFs, the FeCoNi-MOF with equimolar metals hereby prepared exhibited higher peroxidase-like activity, faster colorimetric reaction speed (1.26–2.57 folds), shorter reaction time (20 min) and stronger affinity with TMB (2.50–5.89 folds) and H₂O₂ (1.73–3.94 folds), owing to the splendid synergistic electron transfer effect between Fe, Co and Ni. Considering its outstanding advantages, a promising FeCoNi-MOF-based sensing platform has been designated for the colorimetric detection of the biomarker H₂O₂ and environmental pollutant TP, and lower limits of detection (LODs) (1.75 μM for H₂O₂ and 0.045 μM for TP) and wider linear ranges (6–800 μM for H₂O₂ and 0.5–80 μM for TP) were obtained. In addition, the newly constructed colorimetric platform for TP has been applied successfully for the determination of TP in real water samples with average recoveries ranging from 94.6% to 112.1%. Finally, the colorimetric sensing platform based on FeCoNi-MOF is converted to a cost-effective paper strip sensor, which renders the detection of TP more rapid and convenient.

Aqueous zinc−ion batteries (ZIBs) are widely recognized as highly promising energy storage devices because of their inherent characteristics, including superior safety, affordability, eco−friendliness, and various other benefits. However, the significant corrosion of the zinc metal anode, side reactions occurring between the anode and electrolyte, and the formation of zinc dendrites significantly hinder the practical utilization of ZIBs. Herein, we utilized an electrodeposition method to apply a unique hydrous molybdenum oxide (HMoO_x) layer onto the surface of the zinc metal anode, aiming to mitigate its corrosion and side reactions during the process of zinc deposition and stripping. In addition, the HMoO_x layer not only improved the hydrophilicity of the zinc anode, but also adjusted the migration of Zn²⁺, thus facilitating the uniform deposition of Zn²⁺ to reduce dendrite formation. A symmetrical cell with the HMoO_x−Zn anode displayed reduced−voltage hysteresis (80 mV at 2.5 mA/cm²) and outstanding cycle stability after 3000 cycles, surpassing the performance of the uncoated Zn anode. Moreover, the HMoO_x−Zn anode coupled with a γ−MnO₂ cathode created a considerably more stable rechargeable full battery compared to the bare Zn anode. The HMoO_x−Zn||γ−MnO₂ full cell also displayed excellent cycling stability with a charge/discharge−specific capacity of 129/133 mAh g⁻¹ after 300 cycles. In summary, this research offers a straightforward and advantageous approach that can significantly contribute to the future advancements in rechargeable ZIBs.