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Peripheral neuropathy, a form of nerve damage brought on by diabetes and abnormally high blood sugar, was one of the chronic consequences. Studies reveal that the prevalence of Diabetes Peripheral Neuropathy (DPN) is high and riskier in Males than Females. Also, DPN participants have been examined crucially for physiological variables such as systolic and diastolic blood pressure and body mass index. This study aimed to analyze the potency of Yoga therapy on physiological variables in Males of the age group 35 to 70 having DPN. Yoga connects a person's physical, mental, and spiritual aspects to enhance their health and well-being. It has been proven to treat neurological diseases using Yoga therapy by combining the practice of focused posture (asana), controlled breathing (Pranayama), and meditation. Studies proved 30 males with DPN, 15 in each group, were chosen for the study from the Chennai & Chengalpattu district, Tamilnadu, India. The Experimental Group, Group-I, received a Yoga therapy practice and the control group, Group II, underwent it without any practice. The 12-week training period, six days per week, an hour in the morning. Paired sample t-test was conducted to analyze the data. The calculated 't' value of systolic, diastolic and BMI are 3.486, 2.828, and 1.060, respectively, for Group I and -0.371, -1.547, and -1.792 for Group II. The result shows that the negative t value of Group II shows no significant change in the physiological variables, and Group I data shows a significant improvement in the physiological variables. The calculated 't' value is greater than the table value of 2.14 with a degree of freedom of 14, except for BMI. An extension of the training period is suggested to improve the BMI value. This research study reveals that Yoga Therapy was a significantly more effective treatment for DPN.

INTRODUCTION Lipoma Arborescens is an extremely rare, benign lesion effecting the synovial tissue of joints. It is characterized by villous lipomatous proliferation of the synovial tissue. The aim of our study was to evaluate its diagnostic features and analyse the functional outcome of arthroscopic management. METHODS We studied 13 patients who were diagnosed to have lipoma arborescens at our institution during the period from October 2005 to October 2019. All patients underwent arthroscopic synovectomy. Histopathological examination confirmed the diagnosis. Pre-operative and post-operative functional assessment was done using Tegner Lysholm score. RESULTS Mean age was 46.6 years. All patients presented with progressive swelling of knee joint, while 6 patients also complained of pain. Average duration of symptoms was 34 months. All the patients were diagnosed based on MRI findings. Tegner Lysholm scoring at last follow up visit, had 11 patients with excellent outcome, 1 patient with good outcome, and 1 patient with fair outcome. None of the patients had recurrence, nor underwent any subsequent procedure of the operated joint. CONCLUSIONS Lipoma arborescens is a rare condition which should be a differential in patients with mono-articular swelling of the knee joint, and can be confirmed with MRI. It should not be misdiagnosed or missed at early stages as prolonged duration of symptoms and delay in treatment is likely to lead to development of secondary arthritis of the joint. Arthroscopic synovectomy showed good functional outcome and no recurrence.

The production of hydrogen, a favourable alternative to an unsustainable fossil fuel remains as a significant hurdle with the pertaining challenge in the design of proficient, highly productive and sustainable electrocatalyst for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, the dysprosium (Dy) doped copper oxide (Cu1-xDyxO) nanoparticles were synthesized via solution combustion technique and utilized as a non-noble metal based bi-functional electrocatalyst for overall water splitting. Due to the improved surface to volume ratio and conductivity, the optimized Cu1-xDyxO (x = 0.01, 0.02) electrocatalysts exhibited impressive HER and OER performance respectively in 1 M KOH delivering a current density of 10 mAcm−2 at a potential of −0.18 V vs RHE for HER and 1.53 V vs RHE for OER. Moreover, the Dy doped CuO electrocatalyst used as a bi-functional catalyst for overall water splitting achieved a potential of 1.56 V at a current density 10 mAcm−2 and relatively high current density of 66 mAcm−2 at a peak potential of 2 V. A long term stability of 24 h was achieved for a cell voltage of 2.2 V at a constant current density of 30 mAcm−2 with only 10% of the initial current loss. This showcases the accumulative opportunity of dysprosium as a dopant in CuO nanoparticles for fabricating a highly effective and low-cost bi-functional electrocatalyst for overall water splitting.

The continuous depletion of fossil fuels and the increasing demand for eco-friendly and sustainable energy sources have prompted researchers to look for alternative energy sources. The loss of thermal energy in heat engines (100 °C–350 °C), coal-based thermal plants (150 °C–700 °C), heated water pumping in the geothermal process (150 °C–700 °C), and burning of petrol in the automobiles (150 °C–250 °C) in form of untapped waste-heat can be directly and/or reversibly converted into usable electricity by means of charge carriers (electrons or holes) as moving fluids using thermoelectric (TE) technology, which works based on typical Seebeck effect. The enhancement in TE conversion efficiency has been a key challenge because of the coupled relation between thermal and electrical transport of charge carriers in a given material. In this review, we have deliberated the physical concepts governing the materials to device performance as well as key challenges for enhancing the TE performance. Moreover, the role of crystal structure in the form of chemical bonding, crystal symmetry, order–disorder and phase transition on charge carrier transport in the material has been explored. Further, this review has also emphasized some insights on various approaches employed recently to improve the TE performance, such as, (i) carrier engineering via band engineering, low dimensional effects, and energy filtering effects and (ii) phonon engineering via doping/alloying, nano-structuring, embedding secondary phases in the matrix and microstructural engineering. We have also briefed the importance of magnetic elements on thermoelectric properties of the selected materials and spin Seebeck effect. Furthermore, the design and fabrication of TE modules and their major challenges are also discussed. As, thermoelectric figure of merit, zT does not have any theoretical limitation, an ideal high performance thermoelectric device should consist of low-cost, eco-friendly, efficient, n- or p-type materials that operate at wide-temperature range and similar coefficients of thermal expansion, suitable contact materials, less electrical/thermal losses and constant source of thermal energy. Overall, this review provides the recent physical concepts adopted and fabrication procedures of TE materials and device so as to improve the fundamental understanding and to develop a promising TE device.

BACKGROUND: Sports injuries are very common, and the management demands high degrees of skills and best techniques for an early return to play. The use of Platelet Rich Plasma (PRP) injections in the treatment of tendon, muscle and ligament injuries has become popular. This study observes the outcomes of PRP injections in sports injuries. METHODS: Forty-eight athletes (mean age 29.93 ± 8.48, Male: 37, Female: 11) presenting to a sports medicine centre with different sports injuries with symptom duration (2.81 ± 1.94) months were given PRP injections (single or multiple) four weeks apart with maximum number of injections up to three depending upon the clinical condition, Pre and Post VAS scores. Specific rehabilitation program was administered and compliance was graded by Sports Injury Rehabilitation Adherence Scale (SIRAS). A 1 year follow-up of cases was done for assessing player satisfaction and return to play. RESULTS: Pre-procedure (7.25 ± 0.70) and post-procedure (2.42 ± 0.74) VAS score for all athletes showed significant difference with a p value at 0.0001. The average number of injections was 1.35 ± 1.41 with 72.91% requiring only one injection while 18.75% and 8.33% required two and three injections, respectively. CONCLUSION: Athletes who required a single injection for acute injuries of lower grade returned to sports activity earlier than those who required multiple injections for chronic injuries. PRP injection has optimal effects on sports injuries not responding to conservative management

Unique black coatings were observed in the inner wall of pottery shreds excavated from Keeladi, Tamilnadu, India. Raman spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were used to understand the nature of the coating. The analysis revealed the presence of single, multi-walled carbon nanotubes and layered sheets in the coating. The average diameter of single-walled carbon nanotube found to be about 0.6 ± 0.05 nm. This is the lowest among the single-walled carbon nanotubes reported from artefacts so far and close to the theoretically predicted value (0.4 nm). These nanomaterials were coated in the pottery’s that date backs to sixth century BC, and still retain its stability and adhesion. The findings of nano materials in the pre-historic artifacts, its significance and impact are discussed in this article.

Background A lot of the research has been done worldwide evaluating the capacity of the semitendinosus tendon to regenerate which has not been conducted in the Indian population. Study design 31 patients who underwent unilateral ACL reconstruction with hamstrings were taken into study. All patients underwent ultrasonography imaging of both knees and bilateral isokinetic flexion strength assessment at a one-year postoperative period. Images were obtained at three levels and their dimensions are compared with normal side. Isokinetic testing of the knee is done to evaluate the flexion deficit and is compared to the uninvolved knee. Results Out of a total of 31 patients, 14 patients showed no regeneration, 17 showed regeneration at various levels. On isokinetic testing patients with no regeneration showed the highest mean flexion deficit. Conclusion The semitendinosus tendon and its regeneration can be visualized well using ultrasonography. After semitendinosus harvesting, the flexion strength will be decreased as compared to the normal knee. The flexion strength in patients who have a regenerated tendon will be higher as compared to those who have no regeneration.

The need for a clean and an environmentally non-degrading sustainable energy resource has grown worldwide due to the huge depletion of other fuel sources, as a result, production of hydrogen by electrochemical water splitting is considered as a potential answer to this pertaining need. However, development of low-cost electrocatalyst as a replacement for Pt and RuO2 for both Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) remains a significant challenge for the production of hydrogen at a larger scale. This study presents the synthesis of non-noble metal-based lanthanum doped copper oxide nanoparticles as a potential bi-functional electrocatalyst for overall water splitting in alkaline electrolyte. The optimized 1% lanthanum (La) doped CuO electrocatalyst exhibits outstanding OER and HER activity in 1.0 M KOH electrolyte posting a potential of 1.552 V vs RHE for OER and −0.173 V vs RHE for HER at a current density of ~10 mAcm−2. Significantly, the functional bi-catalyst exhibits a low cell voltage of 1.6 V to achieve overall water splitting at a current density of 10 mAcm−2 along with long-term stability of 13.5 h for a cell voltage of 2.25 V at a constant current density of 30 mAcm−2 with only 20% initial current lose after 13.5 h. The results demonstrate that the incorporation of the rare-earth element onto CuO nanoparticles has made it a viable high-end non-noble electrocatalyst for overall water splitting.

BACKGROUND: Rowing is an Olympic sport gaining popularity in India and injuries are common in these athletes. Determinants of performance, injury risk and training are all interrelated in rowing. Injuries result from various risk factors including fitness issues and improper techniques. Rowers should have adequate leg extension strength and lumbo-pelvic coordination to produce and transmit power from the legs to the oar handle. Biomechanical analysis of the rowing stroke can help in preventing injuries and optimise technique for best performance. It involves a detailed and systematic observation of movement patterns to establish the quality of the movement and provide feedback to the rower about the key variables affecting performance and injury risk. Kinetics such as foot forces and kinematics such as key joint angles can be accurately measured by instrumented foot stretcher and three-dimensional motion capture. AIM: To do a detailed review of literature regarding the incidence and risk factors for rowing injuries and to get an insight on the role of biomechanics in its management. MATERIALS AND METHODS: Literature review was carried out with standard academic search engines and databases including Science Direct, PubMed and Google Scholar using keywords of relevance. A total number of 38 articles were analysed and results were collated to compile this review report. RESULTS: Lumbar spine is most commonly injured (up to 53%), followed by rib cage (9–10%) and shoulder and other anatomical areas. Rowers with a trunk-driven rowing action will have a lower hip:trunk score and carry a high injury risk. A player with lumbar injury will take a minimum of 3–4 months to recover. CONCLUSION: Rowing injuries are common. Regular screening of the rowing athletes by comprehensive fitness and biomechanics assessment will help in prevention of injuries. Rowers need to be tested for pain, strength, flexibility, reproducibility of rowing action with modified mechanics, coordination, fatigue level, explosive power, aerobic and anaerobic endurance. Early recognition of risk factors and timely intervention is the key aspect of a successful return to play.

Thermoelectric generators (TEGs) have received a great attention in the field of renewable energy resources due to their superior ability of converting untapped waste heat into usable electricity. In order to boost the conversion efficiency of TEG and to retrieve the transient heat, this paper demonstrates the role of nanostructured graphite (G) and graphene oxide (GO) decorated phase-change material (PCM) of D-mannitol attached with the hot end of commercial thermoelectric module on enhancement of conversion efficiency and power output. Presence of G and GO on the matric of D-mannitol has been confirmed by powder XRD and FE-SEM. The open circuit voltage ( V oc ) and short circuit current ( I sc ) of TEG attached with PDM, G/PDM, and GO/PDM were recorded for the heating and cooling cycles in the temperature range of 325-450 K. Particularly, the experimentally measured V oc and I sc of TEG with only PDM are 1.23 V and 90 mA, respectively, for the temperature difference of ΔT ∽ 118 K, whereas the maximum V oc of TEG attached with GO/PDM drawn in presence of an external heater is 4.5 V for ΔT ∽ 118 K. Further, the maximum output power of TEG with GO-PCM drawn in the heater-ON and heater-OFF is 1012.5 mW and 450 mW, respectively.

Calcaneocuboid syndrome is a common yet underdiagnosed condition. It has been noted as a FADI scores complication of plantar flexion and inversion ankle injuries which are one of the most common athletic injuries. It is common in ballet dancers and athletes. Presentation of this condition is lateral foot pain which is exaggerated on inversion. To determine the outcomes of a single platelet-rich plasma (PRP) injection combined with rehabilitation for calcaneocuboid syndrome. Six patients (3 non-sportsperson, 2 footballers, 1 basketball player) who presented with complaints of chronic lateral ankle pain were evaluated clinically and radiologically and identified to have calcaneocuboid syndrome. Ultrasound-guided PRP injection was done. Preinjection and one and three months postinjection visual analog scale (VAS) and foot and ankle disability index (FADI) scores were noted. They also underwent a rehabilitation program. One patient was lost to follow-up after 1 month. Five patients showed significant improvement in VAS and FADI at 3 months. The use of PRP has shown proven benefits in the literature. Our study combined PRP along with a rehabilitation program for the subjects. Single PRP injection along with a rehabilitation program has shown to be effective in the management of calcaneocuboid syndrome. Rao V, Anand K, Jaganathan P, et al. Effectiveness of Single Platelet-rich Plasma Injection and Rehabilitation in the Management of Calcaneocuboid Syndrome: A Case Series. J Foot Ankle Surg (Asia Pacific) 2021;8(1):16–18.

Summary GeTe and its derivatives have recently attracted wide attention as promising thermoelectric materials. The principle challenge in optimizing the thermoelectric figure of merit, zT, is the low Seebeck coefficient (S) and high thermal conductivity of GeTe. Here, we report a high zT of ∼2.1 at 723 K in In and Bi co-doped GeTe along with an extremely high TE conversion efficiency of ∼12.3% in a single-leg thermoelectric generator for the temperature difference of 445 K. In and Bi play a distinct but complementary role. In doping significantly enhances the S through the formation of resonance level, which is confirmed with first-principles density functional theory calculations and Pisarenko plot considering two valance band model. However, Bi doping markedly reduces the lattice thermal conductivity due to the formation of extensive solid solution point defects and domain variants. Moreover, a high value of Vickers microhardness (∼200 Hv, Hv = kgf/mm2) reveals excellent mechanical stability.

We report a systematic investigation of the microstructure and thermoelectric properties of refractory element-filled nanostructured Co4Sb12 skutterudites. The refractory tantalum (Ta) metal-filled Co4Sb12 samples (Ta x Co4Sb12 (x = 0, 0.4, 0.6, and 0.8)) are synthesized using a solid-state synthesis route. All the samples are composed of a single skutterudite phase. Meanwhile, nanometer-sized equiaxed grains are present in the Ta0.2Co4Sb12 and Ta0.4Co4Sb12 samples, and bimodal distributions of equiaxed grains and elongated grains are observed in Ta0.6Co4Sb12 and Ta0.8Co4Sb12 samples. The dominant carrier type changes from electrons (n-type) to holes (p-type) with an increase in Ta concentration in the samples. The power factor of the Ta0.6Co4Sb12 sample is increased to 2.12 mW/mK2 at 623 K due to the 10-fold reduction in electrical resistivity. The lowest lattice thermal conductivity observed for Ta0.6Co4Sb12 indicates the rattling action of Ta atoms and grain boundary scattering. Rietveld refinement of XRD data and the analysis of lattice thermal conductivity data using the Debye model confirm that Ta occupies at the voids as well as the Co site. The figure of merit (ZT) of ∼0.4 is obtained in the Ta0.6Co4Sb12 sample, which is comparable to single metal-filled p-type skutterudites reported to date. The thermoelectric properties of the refractory Ta metal-filled skutterudites might be useful to achieve both n-type and p-type thermoelectric legs using a single filler atom and could be one of replacements of the rare earth-filled skutterudites with improved thermoelectric properties.

Discovery of carbon nanotubes in Keeladi potteries

Energy generated in the vehicles depend on the engine and the fuel intake. But usually two thirds of the fuel added to the vehicle, which is, car, trucks bus etc. gets wasted as heat. The energy wasted as heat from areas like engine block, radiator, exhaust pipe engine coolant side and so on. So, to recover the waste heat as usable electrical energy back to the vehicle, Thermoelectric Generator (TEG) can be effectively utilized and its output power could be enhanced by connecting with buck boost converter. Here TEG with coupled inductor is used which produces smooth output with less ripples. TEG is placed in the engine exhaust of the vehicle and the output is connected with buck boost with coupled inductor converter so as to enhance the output voltage. Simulation using Comsol of single stage TEG without Buckboost converter produces an output of 6V.Interestingly TEG with Hotside temperature of 500K and coldside temperature of 300K with 127 legs is connected with buck boost converter with coupled inductor produces the output of 12 V and 0.65 mA is obtained to drive PIR sensor. Moreover in this paper Modified Maximum power point tracker (MPPT) algorithm is proposed to further improve the energy harvesting.

Thermoelectric materials can convert untapped heat to electricity and are expected to have an important role in future energy utilization. IV–VI metal chalcogenides are the most promising candidates for mid-temperature thermoelectric power generation. Among them, PbTe and their alloys have been proven to be the superior thermoelectric materials. Unfortunately, the toxicity of lead (Pb) prevents the application of lead chalcogenides and demands the search for lead-free high-performance solids. This perspective discusses the recent progress of thermoelectric property studies on germanium chalcogenides (GeTe, GeSe, and GeS) for mid-temperature power generation. Here, we have discussed the crystal structure, chemical bonding, and phonon dispersion of germanium chalcogenides to understand the underlying lattice dynamics and low lattice thermal conductivity from a chemistry perspective. We have also discussed the uniqueness of the electronic structure of GeTe and GeSe, which plays an important role in tailoring...

The increase in modern technologies upsurges the pollution of air by ten-fold in the past decade leading to the cause of an increased number of deaths and infectious diseases. This has provoked the research community in developing variable gas sensing materials to detect harmful gases in the present condition. Herein, the lanthanum (La) substituted Ni-Zn-Cu-Co ferrite nanocomposite (La (Ni-Zn-Cu-Co-Fe2O4)) was synthesized via an eco-friendly co-precipitation technique and is utilized as ammonia (NH3) gas sensor. The structural and morphological studies showed the formation of a typical inverse spinel structure of the cubic phase, with spherically agglomerated and interconnected nanostructures. Further, the saturation magnetization (Ms) of the as-synthesized nanocomposite was found to be 1.66 emu using the Vibrating Sample Magnetometer (VSM). The fabricated La (Ni-Zn-Cu-Co-Fe2O4) nanocomposite thin film exhibited an outstanding sensing capability towards ammonia gas with a response and recovery time of 20 s and 15 s respectively, which was on par with the current generation ammonia sensors and posted a sensor response of 86.2% with good repeatability and stability. Moreover, the synthesized material was also found to be more biocompatible, which stands as a bonus.

High density pellets of MnSi1.74, MnSi1.8 and MnSi1.9 were prepared by an induction-melting and a rapid induction hot-pressing. Presence of fine precipitations of metallic MnSi in MnSi1.74 and Si in both MnSi1.8 and MnSi1.9 were confirmed by means of X-ray diffraction, SEM and EDS analysis. With subsequent increase in Si content in HMS, the electrical conductivity gradually decreases and Seebeck coefficient significantly increases. Further, the total thermal conductivity was notably reduced to ~2.1 W/mK at 725 K for MnSi1.8 which resulted in the enhanced zT of ~0.35 at 773 K.

Electrochemical water splitting has considered as an attractive technique in generating clean hydrogen fuel as secondary energy storage. For large-scale production of hydrogen, electrolysis of seawater is considered to the replacement for fresh water due to its natural abundance. However, the alternation requires the development of a robust and cheap electrocatalyst that can perform seawater splitting without undergoing any chloride corrosion at the anode surface. Herein we fabricated a bi-layered anode with dysprosium doped copper oxide (Cu0.98Dy0.02O) electrocatalyst layer coated copper sulfide (CuS) nanodendritic over stainless steel (SS) substrate for Oxygen Evolution Reaction (OER). This optimized bi-layered anode exhibited a superior OER activity posting a potential of 1.57 V vs RHE to achieve the benchmark current density of 10 mA cm−2 in real seawater + 1 M KOH electrolyte without chloride corrosion. On the other hand, a lanthanum doped copper oxide (Cu0.98La0.02O) electrocatalyst layer on a stainless-steel substrate act as a cathode for Hydrogen Evolution Reaction (HER) and exhibited a superior HER activity with a potential of -0.176 V vs RHE to achieve the standard current density in real seawater + 1 M KOH electrolyte. Significantly, the combination of these two electrodes achieved overall alkaline seawater splitting with a cell voltage of 1.53 V to attain the benchmark current density. In addition, long term stability of 12 h was achieved at a low cell voltage of 2.23 V for a current density of 50 mA cm−2 with 100% retention capability. This result demonstrates the advancement in the development of cheaper electrocatalysts for seawater splitting in large-scale hydrogen production.

Complementary and beneficial effects of Sb and Bi codoping in GeTe are shown to generate high thermoelectric figure of merit, zT, of 1.8 at 725 K in Ge1-x-yBixSbyTe samples. Sb and Bi codoping in GeTe facilitates the valence band convergence enhancing the Seebeck coefficient as supported by density functional theoretical (DFT) calculations. Further, Sb and Bi codoping in GeTe releases the rhombohedral strain and increases its tendency to be cubic in structure, which ultimately enhances the valence band degeneracy. At the same time, Bi forms nanoprecipitates of size ∼5–20 nm in GeTe matrix and Sb doping increases solid solution point defects greatly, which altogether scatter low-to mid wavelength phonons and result in reduced lattice thermal conductivity down to 0.5 W/mK in the 300–750 K range.

NiO nanoflakes and nanosheets are successfully synthesized with different anions via homogeneous precipitation method. The prepared samples are characterized by XRD, SEM, TEM-SAED, DRS, PL and VSM analysis. XRD pattern confirms the presence of cubic bunsenite phase with preferred orientation along (2 0 0) direction. SEM images exhibits the presence of nanoflakes, semi-spherical, flower-like and nanosheet shaped particles with an average size 34 nm. The estimated band gap energy and refractive index are found to be in the range 3.79–4.18 eV and 1.48–1.93 respectively. Blue emissions in PL spectrum with a strong band centered at 425 nm and green emission band at 537 nm confirmed presence of crystal defects in NiO lattice. VSM analysis reveals the presence of superparamagnetic and weak ferromagnetic behavior in the NiO nanoparticles.

Waste heat sources are generally diffused and provide a range of temperatures rather than a particular temperature. Thus, thermoelectric waste heat to electricity conversion requires a high average thermoelectric figure of merit (ZTavg ) of materials over the entire working temperature along with a high peak thermoelectric figure of merit (ZTmax ). Herein an ultrahigh ZTavg of 1.4 for (GeTe)80 (AgSbSe2 )20 [TAGSSe-80, T=tellurium, A=antimony, G=germanium, S=silver, Se=selenium] is reported in the temperature range of 300-700 K, which is one of the highest values measured amongst the state-of-the-art Pb-free polycrystalline thermoelectric materials. Moreover, TAGSSe-80 exhibits a high ZTmax of 1.9 at 660 K, which is reversible and reproducible with respect to several heating-cooling cycles. The high thermoelectric performance of TAGSSe-x is attributed to extremely low lattice thermal conductivity (κlat ), which mainly arises due to extensive phonon scattering by hierarchical nano/meso-structures in the TAGSSe-x matrix. Addition of AgSbSe2 in GeTe results in κlat of ≈0.4 W mK-1 in the 300-700 K range, approaching to the theoretical minimum limit of lattice thermal conductivity (κmin ) of GeTe. Additionally, (GeTe)80 (AgSbSe2 )20 exhibits a higher Vickers microhardness (mechanical stability) value of ≈209 kgf mm-2 compared to the other state-of-the-art metal chalcogenides, making it an important material for thermoelectrics.

High-performance thermoelectric materials are desirable in the lower-medium temperature range (450–650 K) for low-grade waste heat recovery. We report a thermoelectric figure of merit (zT) of 1.9 at 585 K in p-type AgSb1–xZnxTe2, which is the highest value measured among the p-type materials in the 450–650 K range. A high average thermoelectric figure of merit (zTavg) of 1.3 is achieved in AgSb0.96Zn0.04Te2. Moreover, the AgSb1–xZnxTe2 sample exhibits a hardness value of ∼6.3 GPa (nanoindentation), which is significantly higher than that of the pristine AgSbTe2. Substitution of Zn in AgSbTe2 suppresses the formation of intrinsic Ag2Te impurity phases, which indeed increases the thermal and mechanical stability. The lattice thermal conductivity for AgSb1–xZnxTe2 samples is reasonably reduced compared to that of the pristine AgSbTe2 because of the significant solid solution point defect phonon scattering. Aliovalent Zn2+ doping in Sb3+ sites in AgSbTe2 increases the p-type carrier concentration, which boost...