Inkless and erasable printing (IEP) based on chromic materials holds great promise to alleviate environmental and sustainable problems. Metal‐organic polymers (MOPs) are bright platforms for constructing IEP materials. However, it is still challenging to design target MOPs with excellent specific functions rationally due to the intricate component‐structure‐property relationships. Herein, an effective strategy was proposed for the rational design IEP‐MOP materials. The stimuli‐responsive viologen moiety was introduced into the construction of MOPs to give it potential chromic behaviors and two different coordination models (i.e. bilateral coordination model, M1; unilateral coordinated model, M2) based on the same viologen ligand were designed. Aided by theoretical calculations, model M1 was recommended secondarily as a more suitable system for IEP materials. Along this line, two representative viologen‐ZnII MOPs 1 and 2 with models M1 and M2 were synthesized successfully. Experiments exhibit that 1 does have quicker stimuli response, stronger color contrast and longer radical lifetime compared to 2. Significantly, the obtained 1‐IEP media brightly inherits the excellent chromic characteristics of 1 and the flexibility of the paper at the same time, which achieves most daily printing requirements, as well as enough resolution and durability to be used in identification by smart device.

Al alloys have widespread industrial applications. However, their mechanical strength is often much lower than steels. Here, we investigate the influence of solutes on achieving ultrahigh strength and thermal stability...

Ionic thermoelectric (i‐TE) gels can have a high thermopower, if the thermodiffusion of mobile cation/anion is decoupled, attracting increasing attentions. Herein, it is shown a high p‐type i‐TE thermopower of 41.8 mV K−1 in agarose‐based ionic thermoelectric gels of AG‐x Na:DBS (AG: agarose, Na:DBS: sodium dodecyl benzene sulfonate). The exclusively high thermopower is relative to the successfully decoupling the thermodiffusion of cation Na+ and anion DBS−. A unique porous structure is formed due to the micellization of the amphiphilic DBS− with the hydrophilic benzenesulfonic group attached to the hydrous agarose gel chains, while the hydrophobic alkyl chain point to the pore centers. As a result, the DBS− micelles are almost immobile as compared with Na+, which can be reconsidered as a part of the gel matrix. The work shines a light on decoupling of cation/anion thermodiffusion through tailoring the microstructure of the quasi‐solid i‐TE materials.

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