High Rate and Long Lifespan Sodium‑Organic Batteries Using Pseudocapacitive Porphyrin Complexes‑Based Cathode

Sodium-organic batteries utilizing natural abundance of sodium element and renewable active materials gain great attentions for grid-scale applications.However,the development is still limited by lack of suitable organic cathode materials with high electronic conductivity that can be operated stably in liquid electrolyte.Herein,we present 5,15-bis(ethynyl)-10,20-diphenylporphyrin(DEPP)and[5,15-bis(ethynyl)-10,20-diphenylporphinato]copper(II)(CuDEPP)as new cathodes for extremely stable sodium-organic batteries.The copper(II)ion partially contributes the charge storage and significantly stabilizes the structure of porphyrin complex for electrochemical energy storage.In situ electrochemical stabilization of organic cathode with a lower charging current density was identified which enables both improved high energy density and power density.An excellent longterm cycling stability up to 600 cycles and an extremely high power density of 28 kW kg−1 were achieved for porphyrin-based cathode.This observation would open new pathway for developing highly stable sodium-organic cathode for electrochemical energy storage.

Thiophene-functionalized porphyrin complexes as high performance electrodes for sodium ion batteries

Organic sodium-ion batteries(OSIBs)using eco-friendly organic materials as electrodes have recently received much attention.However,the practical applications of OSIBs are generally limited by the inherent disadvantages of organic electrodes,such as their low conductivity,poor stability,and high solubility in electrolytes.Herein,we presented[5,10,15,20-tetrathienylporphinato]M(II)(MTTP,M=2H,Ni)as new electrode materials in sodium-organic batteries.The incorporation of thiophene functionalized groups and nickel(II)ion in the molecular design of porphyrins enabled stable and excellent electrochemical performance in sodium storage systems.Benefiting from multiple charge storage sites and bipolar characteristics,the NiTTP anode has a reversible capacity of 434 mAh g^(-1)at a current density of 25 mA g^(-1).An excellent long-term cycling stability and high average voltage were obtained when NiTTP was used as a cathode.In a symmetrical battery,where NiTTP was used as both cathode and anode materials,a high average voltage of 2.3 V and a practical energy density of 93 Wh kg^(-1)was achieved.These results suggest that the thiophene-based porphyrin derivatives would be promising electrode materials for long-term organic sodium ion batteries for green and stable energy storage.

Vacuum Packaging Sensor Based on Time-Resolved Phosphorescence Spectroscopy

Intelligent food packaging with the multisensory analysis is promising as the next generation technology of food packaging.The oxygen content in food packaging is one of the crucial parameters affecting the food quality and shelf life.Caviar is among the most nutritious and costly food sources.Here,a photonic oxygen-sensing system,based on the time-resolved phosphorescence spectroscopy of a platinum complex,is developed for non-contact,non-intrusive,and real-time vacuum packaging quality control,and implemented for caviar packaging.The sensor is embedded in protective polyethylene layers and excited with a short-pulsed light emitting diode(LED)source.Integration of a blue pulsed light source,a fast and amplified silicon photodiode controlled by the Spartan-6 field programmable gate array(FPGA),and a long lifetime platinum complex results in a photonics-based oxygen sensor with a fast response and high sensitivity to the vacum packaging damage,which is suitable for caviar.It is revealed that applying the polyethylene layers protects the caviar from the platinum complex,leaching while not interfering with the sensor functionality.Characterizing the photonic system based on its sensitivity,repeatability,stability,and long-term operation demonstrates its capability for this application.

Recent developments in sensitizers for mesoporous sensitized solar cells

Sensitizers have proven to be extremely important in determining the performance of dye-sensi- tized solar celIs （DSCs）. The design and understanding of sensitizers, especially D-n-A structured porphyrins, has become a recent focus of DSC research. In this perspective article, advances in the conception and performance of various sensitizers including ruthenium complexes, organic dyes and porphyrins are reviewed with respect to their structure and charge transfer dynamics at the dye- sensitized mcsopours heterojunction interface. In particu- lar, the discussion focuses on the trends that perovskite would be the most effective and most likely to be used in DSCs combining with innovative hole transporting materials.