We present a method to fabricate handcrafted thermoelectric devices on standard office paper substrates.The devices are based on thin films of WS_(2),Te,and BP(P-type semiconductors)and TiS_(3)and TiS_(2)(N-type semic...We present a method to fabricate handcrafted thermoelectric devices on standard office paper substrates.The devices are based on thin films of WS_(2),Te,and BP(P-type semiconductors)and TiS_(3)and TiS_(2)(N-type semiconductors),deposited by simply rubbing powder of these materials against paper.The thermoelectric properties of these semiconducting films revealed maximum Seebeck coefficients of(+1.32±0.27)mV K^(-1)and(-0.82±0.15)mV K^(-1)for WS_(2)and TiS_(3),respectively.Additionally,Peltier elements were fabricated by interconnecting the P-and N-type films with graphite electrodes.A thermopower value up to 6.11 mV K^(-1)was obtained when the Peltier element were constructed with three junctions.The findings of this work show proof-of-concept devices to illustrate the potential application of semiconducting van der Waals materials in future thermoelectric power generation as well as temperature sensing for low-cost disposable electronic devices.展开更多
Nowadays,finding cheap and non-toxic materials able to reversibly store high amounts of hydrogen is a challenge in the renewable energy field.Metal sulfides seem to be promising candidates to this purpose.Titanium sul...Nowadays,finding cheap and non-toxic materials able to reversibly store high amounts of hydrogen is a challenge in the renewable energy field.Metal sulfides seem to be promising candidates to this purpose.Titanium sulfides are reported to be particularly interesting but their ability to store hydrogen remains unclear.In this work,titanium based sulfides TiS2 and TiS3 with two-dimensional nanostructures have been synthesized by solid-gas reaction between titanium powder and sulfur at temperatures between 500-600℃.The morphology and crystal structure of Ti-sulfides were characterized by SEM(scanning electronic microscopy)equipped with EDX(energy dispersion X-ray)and XRD(X-ray diffraction),respectively.Their thermal stability was examined by TGA(thermal gravimetric analysis).Their hydrogenation properties have been determined by manometric means using a Sieverts system and by DSC-HP(high-pressure differential scanning calorimetric).Ti-sulfides hardly absorb/adsorb hydrogen for hydrogen pressures up to 80 bar and reaction temperatures up to 300℃.展开更多
By combining ab initio calculations and experiments, we demonstrate how the band gap of the transition metal trichalcogenide TiS3 can be modified by inducing tensile or compressive strain. In addition, using our calcu...By combining ab initio calculations and experiments, we demonstrate how the band gap of the transition metal trichalcogenide TiS3 can be modified by inducing tensile or compressive strain. In addition, using our calculations, we predicted that the material would exhibit a transition from a direct to an indirect band gap upon application of a compressive strain in the direction of easy electrical transport. The ability to control the band gap and its nature could have a significant impact on the use of TiS3 for optical applications. We go on to verify our prediction via optical absorption experiments that demonstrate a band gap increase of up to 9% （from 0.99 to 1.08 eV） upon application of tensile stress along the easy transport direction.展开更多
基金funded by the European Research Council(ERC)under the European Union's Horizon 2020 research and innovation program(grant agreement no.755655,ERC-StG 2017 project 2D-TOPSENSE)the Ministry of Science and Innovation(Spain)through the project PID2020-115566RB-I00+7 种基金the Distinguished Scientist Fellowship Program(DSFP)at King Saud University for partial funding of this workfinancial support from the Agencia Estatal de Investigación of Spain(Grants PID2019-106820RB,RTI2018-097180-B-100,and PGC2018-097018-B-I00)the Junta de Castilla y León(Grants SA256P18 and SA121P20),including funding by ERDF/FEDERfinancial support from Universidad Complutense de Madrid and European Commission(MSCA COFUND UNA4CAREER grant.Project number 4129252)financial support from MICINN(Spain)through the program Juan de la Cierva-Incorporaciónthe financial support of the Spanish Ministry of Industry and Competitiveness to the project MAT2017-84496-Rfinancial support from the Ministry of Science and Innovation(Spain)through the project RT2018-099794-B-100financial support from the Ministry de Universities(Spain)(Ph.D.contract FPU19/04224)
文摘We present a method to fabricate handcrafted thermoelectric devices on standard office paper substrates.The devices are based on thin films of WS_(2),Te,and BP(P-type semiconductors)and TiS_(3)and TiS_(2)(N-type semiconductors),deposited by simply rubbing powder of these materials against paper.The thermoelectric properties of these semiconducting films revealed maximum Seebeck coefficients of(+1.32±0.27)mV K^(-1)and(-0.82±0.15)mV K^(-1)for WS_(2)and TiS_(3),respectively.Additionally,Peltier elements were fabricated by interconnecting the P-and N-type films with graphite electrodes.A thermopower value up to 6.11 mV K^(-1)was obtained when the Peltier element were constructed with three junctions.The findings of this work show proof-of-concept devices to illustrate the potential application of semiconducting van der Waals materials in future thermoelectric power generation as well as temperature sensing for low-cost disposable electronic devices.
文摘Nowadays,finding cheap and non-toxic materials able to reversibly store high amounts of hydrogen is a challenge in the renewable energy field.Metal sulfides seem to be promising candidates to this purpose.Titanium sulfides are reported to be particularly interesting but their ability to store hydrogen remains unclear.In this work,titanium based sulfides TiS2 and TiS3 with two-dimensional nanostructures have been synthesized by solid-gas reaction between titanium powder and sulfur at temperatures between 500-600℃.The morphology and crystal structure of Ti-sulfides were characterized by SEM(scanning electronic microscopy)equipped with EDX(energy dispersion X-ray)and XRD(X-ray diffraction),respectively.Their thermal stability was examined by TGA(thermal gravimetric analysis).Their hydrogenation properties have been determined by manometric means using a Sieverts system and by DSC-HP(high-pressure differential scanning calorimetric).Ti-sulfides hardly absorb/adsorb hydrogen for hydrogen pressures up to 80 bar and reaction temperatures up to 300℃.
文摘By combining ab initio calculations and experiments, we demonstrate how the band gap of the transition metal trichalcogenide TiS3 can be modified by inducing tensile or compressive strain. In addition, using our calculations, we predicted that the material would exhibit a transition from a direct to an indirect band gap upon application of a compressive strain in the direction of easy electrical transport. The ability to control the band gap and its nature could have a significant impact on the use of TiS3 for optical applications. We go on to verify our prediction via optical absorption experiments that demonstrate a band gap increase of up to 9% （from 0.99 to 1.08 eV） upon application of tensile stress along the easy transport direction.
