无铅钙钛矿有望开启压电能量收集新时代

一组研究人员创建了一种充满硫族钙钛矿化合物的聚合物薄膜，该聚合物薄膜在受到压力时可以发电。

Researchers have created a polymer film filled with a chalcogenide perovskite compound that generates electricity when stressed. This phenomenon is known as the piezoelectric effect, which is simply the ability of certain materials to generate an electric charge when mechanical stress is applied.

研究人员创造了一种充满硫族钙钛矿化合物的聚合物薄膜，该化合物在受到压力时可以发电。这种现象称为压电效应，即某些材料在施加机械应力时产生电荷的能力。

The piezoelectric effect occurs in materials that lack crystal structural symmetry. Crystals, ceramics, polymers, and biological matter such as bone, DNA, and various proteins are different kinds of piezoelectric materials.

压电效应发生在缺乏晶体结构对称性的材料中。晶体、陶瓷、聚合物和生物物质（例如骨骼、DNA 和各种蛋白质）是不同种类的压电材料。

Such materials have the potential to collect the energy related to mechanical vibrations. The best thing about this form of energy is that it is present all around us in abundant supply and is renewable in nature.

此类材料具有收集与机械振动相关的能量的潜力。这种能源形式的最大优点是，它在我们周围供应充足，而且本质上是可再生的。

However, as the latest research notes, piezoelectric materials that are best performing tend to have the chemical element lead (Pb), which can cause cancer, increase the risk of brain tumors, and hinder DNA repair.

然而，正如最新研究指出的那样，性能最佳的压电材料往往含有化学元素铅 (Pb)，这种元素会导致癌症、增加患脑肿瘤的风险并阻碍 DNA 修复。

Materials that contain lead are hazardous, and regulators have curtailed their use to protect the environment.

含铅材料是危险的，监管机构已限制其使用以保护环境。

Given the toxicity of lead, which is a heavy, malleable, naturally occurring metal with a relatively low melting point, it is being increasingly phased out of materials and devices.

铅是一种重的、有延展性的、天然存在的金属，熔点相对较低，考虑到它的毒性，它正被越来越多的材料和设备所淘汰。

Hence, the team's goal was to create a material that was lead-free and able to be made inexpensively using elements that are commonly found in nature.

因此，该团队的目标是创造一种无铅材料，并且能够使用自然界中常见的元素以廉价的方式制造。

So, the team from the Rensselaer Polytechnic Institute (RPI) made use of a material that not only does not contain lead but is also one of the few high-performing ones. Hence, it is a great candidate for use in biomedical applications, machines, and infrastructure.

因此，伦斯勒理工学院 (RPI) 的团队使用了一种不仅不含铅而且也是为数不多的高性能材料之一的材料。因此，它是生物医学应用、机器和基础设施的绝佳候选者。

The lead-free material that the team used belongs to the chalcogenide perovskite family exhibiting piezoelectricity. BaZrS3 was the composition used in the study, which is reported to have a pronounced piezoelectric response.

该团队使用的无铅材料属于具有压电性的硫族化物钙钛矿家族。 BaZrS3 是该研究中使用的成分，据报道它具有明显的压电响应。

Chalcogenide perovskites have been gaining a lot of attention and advances lately. This family of compounds is related to perovskite structures, which have many favorable properties such as low toxicity, high stability, direct band gaps, good carrier transport abilities, and strong light absorption.

硫属化物钙钛矿最近受到了广泛的关注并取得了进展。该类化合物与钙钛矿结构有关，具有低毒性、高稳定性、直接带隙、良好的载流子传输能力和强光吸收等许多有利特性。

These properties make perovskites really stand out in applications like photovoltaics, photodetectors, light-emitting devices, and photocatalysts.

这些特性使钙钛矿在光伏、光电探测器、发光器件和光催化剂等应用中真正脱颖而出。

Interestingly, most high-performing piezoelectric materials are non-centrosymmetric and hence display intrinsically high polarizability. However, many oxide perovskites, including the one used in the study, exhibit a centrosymmetric crystal structure, which is weakly piezoelectric in its pristine form. These compounds are actually non-polar because they inherently lack a net dipole moment.

有趣的是，大多数高性能压电材料都是非中心对称的，因此表现出本质上高的极化率。然而，许多氧化物钙钛矿，包括研究中使用的氧化物钙钛矿，表现出中心对称晶体结构，其原始形式具有弱压电性。这些化合物实际上是非极性的，因为它们本质上缺乏净偶极矩。

The dipole moment is the scientific name for the way piezoelectric materials perform when under stress, which is deformation in a way that causes positive ions and negative ions in the material to separate. This dipole moment can be harnessed and turned into an electric current.

偶极矩是压电材料在应力下表现方式的科学名称，即导致材料中的正离子和负离子分离的变形。可以利用该偶极矩并将其转化为电流。

But with no net dipole moment, how did the team achieve piezoelectricity? Well, they leverage the loose packing within the chalcogenide perovskite structure to overcome the problem.

但在没有净偶极矩的情况下，该团队是如何实现压电性的呢？那么，他们利用硫族化物钙钛矿结构内的松散堆积来克服这个问题。

Scaling the Technology for Green Energy Applications

扩展绿色能源应用技术

The latest study details that despite being centrosymmetric, lead-free chalcogenide perovskite materials become polarizable very quickly when it is deformed. This is due to a loosely packed unit cell, which has a lot of vacant space.

最新研究详细说明，尽管无铅硫属化物钙钛矿材料具有中心对称性，但在变形时会很快变得极化。这是由于单元电池结构松散，有大量空闲空间。

This significant volume of empty space allows extended displacement of ions, which, in turn, allows for the reduction of symmetry and results in an amplified displacement-mediated dipole moment.

这种巨大的空白空间允许离子的扩展位移，这反过来又允许对称性的降低并导致位移介导的偶极矩的放大。

The team performed a piezoresponse force microscopy (PFM) on BaZrS3 to confirm the piezoelectricity of the material.

该团队对 BaZrS3 进行了压电响应力显微镜 (PFM)，以确认该材料的压电性。

PFM is a functional atomic force microscopy (AFM) model that has been recognized for the unique information it offers on the electromechanical properties of various materials on the nanometer scale.

PFM 是一种功能性原子力显微镜 (AFM) 模型，因其在纳米尺度上提供各种材料机电特性的独特信息而受到认可。

Structural symmetry in the chalcogenide perovskite material, as per the team, can be easily broken under stress, which leads to an enhanced piezoelectric response. So, once confirmed, the team developed composites of BaZrS3 particles dispersed in polycaprolactone.

研究小组表示，硫族化物钙钛矿材料的结构对称性在压力下很容易被破坏，从而增强压电响应。因此，一旦得到证实，该团队就开发了分散在聚己内酯中的 BaZrS3 颗粒的复合材料。

The new material synthesized contains barium, zirconium, and sulfur, which were then used to harvest energy from human body motion and power electrochemical and electronic devices.

合成的新材料含有钡、锆和硫，然后用于从人体运动中获取能量，并为电化学和电子设备提供动力。

The team tested the material's ability to generate electricity by subjecting it to bodily movements like running, walking, tapping fingers, and clapping. The electricity produced during the experiment was found to be enough to power LED banks, spelling out RPI.

研究小组通过跑步、行走、敲击手指和拍手等身体动作来测试这种材料的发电能力。实验期间产生的电力足以为 LED 组供电，即 RPI。

“We are excited and encouraged by our findings and their potential to support the transition to green energy.”

“我们对我们的发现及其支持向绿色能源过渡的潜力感到兴奋和鼓舞。”

– Nikhil Koratkar, Study co-author

– Nikhil Koratkar，研究合著者

The material, according to him, converts mechanical energy into electrical energy. According to Koratkar:

据他介绍，这种材料将机械能转化为电能。根据科拉特卡的说法：

“The greater the applied pressure load and the greater the surface area over which the pressure is applied, the greater the effect.”

“施加的压力负载越大，施加压力的表面积越大，效果就越大。”

The energy harvesting film created by the team is just 0.3 millimeters thick and can be integrated into various machines, devices, and structures like buildings and highways to

该团队制造的能量收集薄膜厚度仅为 0.3 毫米，可以集成到各种机器、设备以及建筑物和高速公路等结构中，