Though numerous nanomaterials with enzyme-like activities have been utilized as probes and sensors for detecting biological molecules, it is still challenging to construct highly sensitive detectors for biomarkers using polymeric materials. Benefiting from the π-d delocalization effect of electrons, excellent metal-chelating property, high electron transferability, and good chemical stability of πconjugated phthalocyanine, the design of the copper phthalocyanine-based conjugated polymer nanoparticles (Cu-PcCP NPs) as a colorimetric sensor for a variety of biomarkers is reported. The Cu-PcCP NPs are synthesized through a simple microwave-assisted polymerization, and their chemical structures are thoroughly characterized. The colorimetric results of Cu-PcCP NPs demonstrate excellent peroxidase-like detecting activity and also great substrate selectivity than most of the reported Cu-based nanomaterials. The Cu-PcCP NPs can achieve a detection limit of 4.88 μM for the H 2 O 2 , 4.27 μM for the L-cysteine, and 21.10 μM for the glucose via a cascade catalytic system, which shows comparable detecting sensitivity as that of many earlier reported enzyme-like nanomaterials. Moreover, Cu-PcCP NPs present remarkable resistance to harsh conditions, including high temperature, low pH, and excessive salts. These highly specific π-conjugated copper-phthalocyanine nanoparticles not only overcome the current limitation of polymeric material-based sensors but also provide a new direction for designing next-generation enzyme-like nanomaterial-based colorimetric biosensors.

Metal‐porphyrins or metal‐phthalocyanines‐based organic frameworks (POFs), an emerging family of metal‐N‐C materials, have attracted widespread interest for application in electrocatalysis due to their unique metal‐N4 coordination structure, high conjugated π‐electron system, tunable components, and chemical stability. The key challenges of POFs as high‐performance electrocatalysts are the need for rational design for porphyrins/phthalocyanines building blocks and an in‐depth understanding of structure–activity relationships. Herein, the synthesis methods, the catalytic activity modulation principles, and the electrocatalytic behaviors of 2D/3D POFs are summarized. Notably, detailed pathways are given for modulating the intrinsic activity of the M‐N4 site by the microenvironments, including central metal ions, substituent groups, and heteroatom dopants. Meanwhile, the topology tuning and hybrid system, which affect the conjugation network or conductivity of POFs, are also considered. Furthermore, the representative electrocatalytic applications of structured POFs in efficient and environmental‐friendly energy conversion areas, such as carbon dioxide reduction reaction, oxygen reduction reaction, and water splitting are briefly discussed. Overall, this comprehensive review focusing on the frontier will provide multidisciplinary and multi‐perspective guidance for the subsequent experimental and theoretical progress of POFs and reveal their key challenges and application prospects in future electrocatalytic energy conversion systems.

The development of polymer electrolyte membrane electrolysis of water is mainly limited by the high cost of noble metals and inadequate stability owing to the slow reaction kinetics of the oxygen evolution reaction and the restrictions of strongly acidic operating environments. To improve the utilization of noble metals, we use Ti-doped SnO2 as a carrier to support active species IrO2. The results show that the introduction of Ti element can inhibit the grain growth and help to improve the electrical conductivity of SnO2. Electrochemical tests for the catalysts show that 40 wt % IrO2/TSO has the best mass-normalized charge (231.24 C g–1 IrO2) and current density (714.85 A g–1 IrO2) at 1.6 V with the overpotential of only 271 mV at 10 mA cm–2, which is attributed to the outstanding dispersion effect of Ti-doped SnO2 and the synergy between the active species and the introduction of Ti element. The comprehensive advantages exhibited by the Ti-doped SnO2 support provide an alternative solution to reduce the cost of noble metal catalysts by improving the catalytic activity and stability.

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