Will power \”Jelly\” – Giant thermopower ion thermoelectric material

Jelly kids love to eat dessert, but robots do not eat, only needs to be charged. Materials Science and Engineering, South University of Technology associate professor Liu Wei book Task Force broke this knowledge – the researchers using the latest original research, made a [123 ] can generate a \”jelly\” . \”Jelly\” The main substance is extracted from animal bones gelatin polymer material, not only as food on the table, is also an important industrial raw materials. Recently, STSP Liu Wei book discussion group and the Massachusetts Institute of Technology Academician Chen Gang Task Force cooperation obtained in the rt ionic breakthrough thermoelectric material , a synergistic effect reduction reaction entropy electrically entropy by diffusion of ions and achieve a high oxide 17 mV / K in the the quasi-solid gel ion giant thermopower effect (Figure 1). Research published in the top journal \”Science\” (Science) in the form of First release.

Figure 1. Giant thermoelectric potential ionic type thermoelectric materials. Ionic thermoelectric material Gelatin-x KCl-m prepared in (A) of the work / n FeCN4- / 3- thermoelectric power comparison chart (x and m / n is the molar concentration, FeCN4- / 3- is Fe (CN) 64- / Fe (CN) 63-), wherein Gelatin (x = 0 m, m / n = 0 m), Gelatin-FeCN4- / 3- (x = 0 m, m / n = 0.42 / 0.25 m), Gelatin- KCl (x = 0.8 m, m / n = 0 m) and gelatin-KCl-FeCN4- / 3- (x = 0.8 m, m / n = 0.42 / 0.25 m, water / gelatin volume ratio rv = 2.0 and 3.0) ; (B) using the present work and report thermodiffusion effect and the absolute thermoelectric power thermogalvanic effect.Based on the Seebeck effect of the thermoelectric conversion material of thermal energy can be achievedDirect conversion between electrical energy, can provide a sustainable energy things work for small sensors in the system or electronic device. Currently, based on conventional electronic type thermoelectric conversion material (e-TE) at room temperature captured energy may reach milliwatt output power, but is limited by thermoelectric power semiconductor electro-acoustic behavior of transport, it is about 200 μV optimization / about K. Voltage obtained 1 ~ 5 V for the normal operation of the sensor, the material needs to thousands of n / p thermocouples connected in series, the device increases the complexity and integration; or increase the need for external voltage boost chip, but increase power consumption and improve the cost.

Ion type thermoelectric conversion material having a high thermoelectric power, thermoelectric power generation in the form of generally divided into two forms: one is the effect of thermal diffusion using ion (Thermodiffusion Effect), namely the use of ion temperature difference directed migration entropy change caused by the density difference to achieve thermal conversion to electricity, which is similar to the Seebeck effect in electron energy carrier; the other is the use of oxidation / reduction potential of the temperature effect (Thermogalvanic effect), i.e., an oxidation / entropy reduction reaction is increased to achieve thermal transition electricity. The theoretical and experimental work from two angles illustrate the negative effects thermogalvanic thermodiffusion effect and the potential of the p-type thermoelectric temperature coefficient of synergy can be thereby generating a high p-type thermoelectric potential (Figure 2).

Figure 2 synergistic mechanism. Ionic type thermoelectric material prepared in (A) of the working voltage distribution and the electrochemical potential, E is the internal electric field. (A) Gelatin-KCl, (B) Gelatin-FeCN4- / 3 -, (C) Gelatin-KCl-FeCN4- / 3-.Researchers aligned with a solid ion-type thermoelectric conversion device

proposed a new quasi-continuous hot charge / discharge operating mode, the device 100 turns cycle operation to achieve long working for 5 hours. Researchers 25 5 × 5 × 1.8 mm quasi-solid ionic thermoelectric unit assembled in series into a flexible wearable device, the device using the body temperature difference of up to 2.2 V voltage and the maximum output power 5μW (FIG. 3) . The carrier operates to achieve thermal energy ionElectrical conversion to the sensor system and things to achieve the desired electronic device from the power supply provides a choice.

Figure 3. The proof of concept of an ionic wearable thermoelectric device. (A) schematic drawing; (B) from 25 units (Cu|i-TE|Cu, 5 × 5 × 1.8 mm) consisting of ionic wearable thermoelectric device using the voltage variation of the body temperature difference; (C) Discharge during the power – voltage – current changes; (D) wearable i-TE and e-TE device using the body temperature of the power recovery performance comparison of FIG. Room Temperature thermoelectric materials and devicesLiu Wei book primarily engaged. 2017, Liu Wei for the Material Today Physics book written an article entitled \”New trends, strategies and opportunities in thermoelectric materials: A perspective\” invited review papers, presented \”Go beyond Seebeck effect\” outlook. Has experienced many failures, Liu Wei book discussion group finally found inspiration in the \”jelly\”, the research and development of a new type of thermoelectric material at room temperature with ion energy carrier. The theoretical aspects of the work has been an important breakthrough in support of academician Chen Gang. Liu Wei book said that in addition to scientific exploration has insisted when faced with setbacks, also can not do without the guidance of a mentor. \”It was found that the giant thermoelectric effect, bring us the joy was short-lived and a bunch of questions, the repeated scrutiny and research partners to answer a question raised by Academician Chen Gang when we come to experience the charm and significance of research: research is hands-on, to explore and discover; study is brains, to think about the very poor truth, inquiring. \” The first author of the paper is Liu Wei book postdoctoral research group

Korea successfully , co-first authors, MIT postdoctoral Qian Xin for the paper an important contribution in theoretical explanation synergies. Liu Wei book and Gang corresponding author for the paper, paper for the South University of Technology first communication unit. Participation of the author\’s thesis also included Professor of Physics STSP Zhang Wenqing , Nankai University professor Wang Wei super , Associate Professor University of Hong KongGrant Pingxian Ping , and 2018 STSP – HKU with culture PhD LI which Kai , 2017 STSP – HIT associated training doctoral Zhu Yongbin , 2018 STSP – Master culture HIT-linking DENG ment , NTUT visiting students Han Zhijia and the like. The work was SUSTech-MIT mechanical engineering education and research center, creating wide support for the project team and Tencent Charity Foundation \”Scientific Exploration Award\” program. Papers link: https: //science.sciencemag.org/content/early/2020/04/29/science.aaz5045/tab-pdf